Articles | Volume 11, issue 9
Atmos. Meas. Tech., 11, 4981–5006, 2018
https://doi.org/10.5194/amt-11-4981-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue: Towards Unified Error Reporting (TUNER)
Atmos. Meas. Tech., 11, 4981–5006, 2018
https://doi.org/10.5194/amt-11-4981-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
04 Sep 2018
Research article
| 04 Sep 2018
Evaluation of MUSICA IASI tropospheric water vapour profiles using theoretical error assessments and comparisons to GRUAN Vaisala RS92 measurements
Christian Borger et al.
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Maximilian Herrmann, Moritz Schöne, Christian Borger, Simon Warnach, Thomas Wagner, Ulrich Platt, and Eva Gutheil
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-334, https://doi.org/10.5194/acp-2022-334, 2022
Preprint under review for ACP
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Ozone depletion events (ODEs) are a common occurence in the boundary layer during Arctic spring. Ozone is depleted by bromine species in an auto-catalytic reaction cycle. Previous modeling studies assumed an infinite bromine source at the ground. An alternative emission scheme is presented in which a finite amount of bromide in the snow is tracked over time. The Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) is used to study ODEs in the Arctic from February to May 2019.
Steffen Beirle, Christian Borger, Steffen Dörner, Vinod Kumar, and Thomas Wagner
Atmos. Meas. Tech., 15, 987–1006, https://doi.org/10.5194/amt-15-987-2022, https://doi.org/10.5194/amt-15-987-2022, 2022
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We present a formalism that relates the vertical column density (VCD) of the oxygen collision complex O4 to surface values of temperature and pressure, based on physical laws. In addition, we propose an empirical modification which also accounts for surface relative humidity (RH). This allows for simple and quick but still accurate calculation of the O4 VCD without the need for constructing full vertical profiles, which is expected to be useful in particular for MAX-DOAS applications.
Christian Borger, Steffen Beirle, and Thomas Wagner
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-149, https://doi.org/10.5194/acp-2022-149, 2022
Preprint under review for ACP
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In this study, we analyze trends of total column water vapour (TCWV) using multiple years of satellite observations and find on global average an increase in the TCWV amount by about 0.24 % per year. Further investigations of the hydrological cycle reveal that the assumption of temporally invariant relative humidity is not always fulfilled and that its responses to global warming are 2 to 4 times higher than theoretically expected or previously reported values.
Tobias Küchler, Stefan Noël, Heinrich Bovensmann, John Philip Burrows, Thomas Wagner, Christian Borger, Tobias Borsdorff, and Andreas Schneider
Atmos. Meas. Tech., 15, 297–320, https://doi.org/10.5194/amt-15-297-2022, https://doi.org/10.5194/amt-15-297-2022, 2022
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We applied the air-mass-corrected differential optical absorption spectroscopy (AMC-DOAS) method to derive total column water vapour (TCWV) from Sentinel-5P measurements and compared it to independent data sets. The correlation coefficients of typically more than 0.9 and the small deviations up to 2.5 kg m−2 reveal good agreement between our data product and other TCWV data sets. In particular for the different Sentinel-5P water vapour products, the deviations are around 1 kg m−2.
Jānis Puķīte, Christian Borger, Steffen Dörner, Myojeong Gu, and Thomas Wagner
Atmos. Chem. Phys., 22, 245–272, https://doi.org/10.5194/acp-22-245-2022, https://doi.org/10.5194/acp-22-245-2022, 2022
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Chlorine dioxide (OClO) is an indicator for chlorine activation. New OClO data by TROPOMI (S5P) are interpreted in a meteorological context and related to CALIOP PSC observations. We report very high OClO levels for the northern hemispheric winter 2019/20 with an extraordinarily long period with a stable polar vortex. A minor stratospheric warming in the Southern Hemisphere was also observed in September 2019, where usual OClO values rapidly deactivated 1–2 weeks earlier.
Christian Borger, Steffen Beirle, and Thomas Wagner
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2021-319, https://doi.org/10.5194/essd-2021-319, 2021
Preprint under review for ESSD
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This study presents a long-term data set of monthly mean total column water vapour (TCWV) based on measurements of the Ozone Monitoring Instrument (OMI) covering the time range from January 2005 to December 2020. We describe how the TCWV values are retrieved from UV-vis satellite spectra and demonstrate that the OMI TCWV data set is in good agreement to various different reference data sets. Moreover, we also show that it fulfills typical stability requirements for climate data records.
Jānis Puķīte, Christian Borger, Steffen Dörner, Myojeong Gu, Udo Frieß, Andreas Carlos Meier, Carl-Fredrik Enell, Uwe Raffalski, Andreas Richter, and Thomas Wagner
Atmos. Meas. Tech., 14, 7595–7625, https://doi.org/10.5194/amt-14-7595-2021, https://doi.org/10.5194/amt-14-7595-2021, 2021
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Chlorine dioxide (OClO) is used as an indicator for chlorine activation. We present a new differential optical absorption spectroscopy retrieval algorithm for OClO from measurements of TROPOMI on the Sentinel-5P satellite. To achieve a substantially improved accuracy for the weak absorber OClO, we consider several additional fit parameters accounting for various higher-order spectral effects. The retrieved OClO slant column densities are compared with ground-based zenith sky measurements.
Steffen Beirle, Christian Borger, Steffen Dörner, Henk Eskes, Vinod Kumar, Adrianus de Laat, and Thomas Wagner
Earth Syst. Sci. Data, 13, 2995–3012, https://doi.org/10.5194/essd-13-2995-2021, https://doi.org/10.5194/essd-13-2995-2021, 2021
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A catalog of point sources of nitrogen oxides was created using satellite observations of NO2. Key for the identification of point sources was the divergence, i.e., the difference between upwind and downwind levels of NO2.
The catalog lists 451 locations, of which 242 could be automatically matched to power plants. Other point sources are metal smelters, cement plants, or industrial areas. The catalog thus allows checking and improving of existing emission inventories.
Holger Sihler, Steffen Beirle, Steffen Dörner, Marloes Gutenstein-Penning de Vries, Christoph Hörmann, Christian Borger, Simon Warnach, and Thomas Wagner
Atmos. Meas. Tech., 14, 3989–4031, https://doi.org/10.5194/amt-14-3989-2021, https://doi.org/10.5194/amt-14-3989-2021, 2021
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MICRU is an algorithm for the retrieval of effective cloud fractions (CFs) from satellite measurements. CFs describe the amount of clouds, which have a significant impact on the vertical sensitivity profile of trace gases like NO2 and HCHO. MICRU retrieves small CFs with an accuracy of 0.04 over the entire satellite swath. It features an empirical surface reflectivity model accounting for physical anisotropy (BRDF, sun glitter) and instrumental effects. MICRU is also applicable to imager data.
Thomas Wagner, Steffen Beirle, Steffen Dörner, Christian Borger, and Roeland Van Malderen
Atmos. Chem. Phys., 21, 5315–5353, https://doi.org/10.5194/acp-21-5315-2021, https://doi.org/10.5194/acp-21-5315-2021, 2021
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A global long-term (1995–2015) data set of total column water vapour (TCWV) derived from satellite observations is used to quantify the influence of teleconnections. Based on a newly developed empirical method more than 40 teleconnection indices are significantly detected in our global TCWV data set. After orthogonalisation, only 20 indices are left significant. The global distribution of the cumulative influence of teleconnection indices is strongest in the tropics and high latitudes.
Christian Borger, Steffen Beirle, Steffen Dörner, Holger Sihler, and Thomas Wagner
Atmos. Meas. Tech., 13, 2751–2783, https://doi.org/10.5194/amt-13-2751-2020, https://doi.org/10.5194/amt-13-2751-2020, 2020
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We present a total column water vapour (TCWV) retrieval analysing measurements from S-5P/TROPOMI in the visible blue spectral range. The retrieval can well capture the global water vapour distribution with similar sensitivity over the land and ocean and agrees well with various reference data sets within the estimated TCWV uncertainties of typically around 10 %–20 %.
Omaira E. García, Matthias Schneider, Benjamin Ertl, Eliezer Sepúlveda, Christian Borger, Christopher Diekmann, Andreas Wiegele, Frank Hase, Sabine Barthlott, Thomas Blumenstock, Uwe Raffalski, Angel Gómez-Peláez, Martin Steinbacher, Ludwig Ries, and Angel M. de Frutos
Atmos. Meas. Tech., 11, 4171–4215, https://doi.org/10.5194/amt-11-4171-2018, https://doi.org/10.5194/amt-11-4171-2018, 2018
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This work presents the CH4 and N2O products of the MUSICA IASI processor. We analytically assess precisions of 1.5–3 %, good sensitivity in the UTLS region (for CH4 and N2O) and a possibility for retrieving free-tropospheric CH4 at low latitudes independently from CH4 in the UTLS. This is confirmed by comparison to HIPPO profile data (covering a large latitudinal range), continuous GAW data (covering 9 years) and NDACC FTIR data (covering 10 years and three different climate zones).
Matthias Schneider, Christian Borger, Andreas Wiegele, Frank Hase, Omaira E. García, Eliezer Sepúlveda, and Martin Werner
Atmos. Meas. Tech., 10, 507–525, https://doi.org/10.5194/amt-10-507-2017, https://doi.org/10.5194/amt-10-507-2017, 2017
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The characteristics of {H2O,δD} pair space-based remote sensing data depend on the atmospheric and surface conditions, which compromises their usage for model evaluation studies. This paper shows how the problem can be overcome by simulating MUSICA MetOp/IASI {H2O,δD} remote sensing products for any given model atmosphere. The remote sensing retrieval simulator is freely provided as a MATLAB and Python routine.
Stefan Noël, Maximilian Reuter, Michael Buchwitz, Jakob Borchardt, Michael Hilker, Oliver Schneising, Heinrich Bovensmann, John P. Burrows, Antonio Di Noia, Robert J. Parker, Hiroshi Suto, Yukio Yoshida, Matthias Buschmann, Nicholas M. Deutscher, Dietrich G. Feist, David W. T. Griffith, Frank Hase, Rigel Kivi, Cheng Liu, Isamu Morino, Justus Notholt, Young-Suk Oh, Hirofumi Ohyama, Christof Petri, David F. Pollard, Markus Rettinger, Coleen Roehl, Constantina Rousogenous, Mahesh Kumar Sha, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Yao Té, Voltaire A. Velazco, Mihalis Vrekoussis, and Thorsten Warneke
Atmos. Meas. Tech., 15, 3401–3437, https://doi.org/10.5194/amt-15-3401-2022, https://doi.org/10.5194/amt-15-3401-2022, 2022
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We present a new version (v3) of the GOSAT and GOSAT-2 FOCAL products.
In addition to an increased number of XCO2 data, v3 also includes products for XCH4 (full-physics and proxy), XH2O and the relative ratio of HDO to H2O (δD). For GOSAT-2, we also present first XCO and XN2O results. All FOCAL data products show reasonable spatial distribution and temporal variations and agree well with TCCON. Global XN2O maps show a gradient from the tropics to higher latitudes on the order of 15 ppb.
Qiansi Tu, Frank Hase, Zihan Chen, Matthias Schneider, Omaira García, Farahnaz Khosrawi, Thomas Blumenstock, Fang Liu, Kai Qin, Song Lin, Hongyan Jiang, and Dianjun Fang
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2022-176, https://doi.org/10.5194/amt-2022-176, 2022
Preprint under review for AMT
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Three-year TROPOMI observations are used to derive tropospheric NO2 emissions in two mega(cities), where high anthropogenic activities exist. The wind-assigned anomalies are calculated, and the emission rates and spatial patterns are estimated based on a Machine Learning algorithm. The results are in reasonable agreement with the previous studies and the inventory. Our method is quite robust and can be served as a simple method to estimate the emissions of NO2 and other gases in other regions.
Maximilian Rißmann, Jia Chen, Gregory Osterman, Florian Dietrich, Moritz Makowski, Xinxu Zhao, Frank Hase, and Matthäus Kiel
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2022-71, https://doi.org/10.5194/amt-2022-71, 2022
Preprint under review for AMT
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The Orbiting Carbon Observatory 2 (OCO-2) measures atmospheric concentrations of the most potent greenhouse gas CO2 globally. By comparing its measurements to a ground-based monitoring network in Munich (MUCCnet), we find that the satellite is able to reliably detect urban CO2 concentrations. Furthermore, spatial CO2 differences captured by OCO-2 and MUCCnet are strongly correlated, which indicates that OCO-2 could be helpful in determining urban CO2 emissions from space.
Maximilian Herrmann, Moritz Schöne, Christian Borger, Simon Warnach, Thomas Wagner, Ulrich Platt, and Eva Gutheil
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-334, https://doi.org/10.5194/acp-2022-334, 2022
Preprint under review for ACP
Short summary
Short summary
Ozone depletion events (ODEs) are a common occurence in the boundary layer during Arctic spring. Ozone is depleted by bromine species in an auto-catalytic reaction cycle. Previous modeling studies assumed an infinite bromine source at the ground. An alternative emission scheme is presented in which a finite amount of bromide in the snow is tracked over time. The Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) is used to study ODEs in the Arctic from February to May 2019.
Beatriz Herrera, Alejandro Bezanilla, Thomas Blumenstock, Enrico Dammers, Frank Hase, Lieven Clarisse, Adolfo Magaldi, Claudia Rivera, Wolfgang Stremme, Kimberly Strong, Camille Viatte, Martin Van Damme, and Michel Grutter
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-217, https://doi.org/10.5194/acp-2022-217, 2022
Preprint under review for ACP
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This work investigates atmospheric ammonia (NH3), a key trace gas with consequences for the environment and human health, in Mexico City. The results from the ground-based and satellite instruments show the variability and spatial distribution of NH3 over this region. NH3 in Mexico City has been increasing for the past ten years and most of its sources are urban. This work contributes to a better understanding of NH3 sources and variability in urban and remote areas.
Andreas Luther, Julian Kostinek, Ralph Kleinschek, Sara Defratyka, Mila Stanisavljević, Andreas Forstmaier, Alexandru Dandocsi, Leon Scheidweiler, Darko Dubravica, Norman Wildmann, Frank Hase, Matthias M. Frey, Jia Chen, Florian Dietrich, Jarosław Nȩcki, Justyna Swolkień, Christoph Knote, Sanam N. Vardag, Anke Roiger, and André Butz
Atmos. Chem. Phys., 22, 5859–5876, https://doi.org/10.5194/acp-22-5859-2022, https://doi.org/10.5194/acp-22-5859-2022, 2022
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Coal mining is an extensive source of anthropogenic methane emissions. In order to reduce and mitigate methane emissions, it is important to know how much and where the methane is emitted. We estimated coal mining methane emissions in Poland based on atmospheric methane measurements and particle dispersion modeling. In general, our emission estimates suggest higher emissions than expected by previous annual emission reports.
Omaira Elena García, Esther Sanromá, Matthias Schneider, Frank Hase, Sergio Fabián León-Luis, Thomas Blumenstock, Eliezer Sepúlveda, Alberto Redondas, Virgilio Carreño, Carlos Torres, and Natalia Prats
Atmos. Meas. Tech., 15, 2557–2577, https://doi.org/10.5194/amt-15-2557-2022, https://doi.org/10.5194/amt-15-2557-2022, 2022
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Accurate observations of atmospheric ozone (O3) are essential to monitor in detail its key role in atmospheric chemistry. In this context, this paper has assessed the effect of using different retrieval strategies on the quality of O3 products from ground-based NDACC FTIR (Fourier transform infrared) spectrometry, with the aim of providing an improved O3 retrieval that could be applied at any NDACC FTIR station.
Carlos Alberti, Frank Hase, Matthias Frey, Darko Dubravica, Thomas Blumenstock, Angelika Dehn, Paolo Castracane, Gregor Surawicz, Roland Harig, Bianca C. Baier, Caroline Bès, Jianrong Bi, Hartmut Boesch, André Butz, Zhaonan Cai, Jia Chen, Sean M. Crowell, Nicholas M. Deutscher, Dragos Ene, Jonathan E. Franklin, Omaira García, David Griffith, Bruno Grouiez, Michel Grutter, Abdelhamid Hamdouni, Sander Houweling, Neil Humpage, Nicole Jacobs, Sujong Jeong, Lilian Joly, Nicholas B. Jones, Denis Jouglet, Rigel Kivi, Ralph Kleinschek, Morgan Lopez, Diogo J. Medeiros, Isamu Morino, Nasrin Mostafavipak, Astrid Müller, Hirofumi Ohyama, Paul I. Palmer, Mahesh Pathakoti, David F. Pollard, Uwe Raffalski, Michel Ramonet, Robbie Ramsay, Mahesh Kumar Sha, Kei Shiomi, William Simpson, Wolfgang Stremme, Youwen Sun, Hiroshi Tanimoto, Yao Té, Gizaw Mengistu Tsidu, Voltaire A. Velazco, Felix Vogel, Masataka Watanabe, Chong Wei, Debra Wunch, Marcia Yamasoe, Lu Zhang, and Johannes Orphal
Atmos. Meas. Tech., 15, 2433–2463, https://doi.org/10.5194/amt-15-2433-2022, https://doi.org/10.5194/amt-15-2433-2022, 2022
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Space-borne greenhouse gas missions require ground-based validation networks capable of providing fiducial reference measurements. Here, considerable refinements of the calibration procedures for the COllaborative Carbon Column Observing Network (COCCON) are presented. Laboratory and solar side-by-side procedures for the characterization of the spectrometers have been refined and extended. Revised calibration factors for XCO2, XCO and XCH4 are provided, incorporating 47 new spectrometers.
Carlos Alberti, Qiansi Tu, Frank Hase, Maria V. Makarova, Konstantin Gribanov, Stefani C. Foka, Vyacheslav Zakharov, Thomas Blumenstock, Michael Buchwitz, Christopher Diekmann, Benjamin Ertl, Matthias M. Frey, Hamud Kh. Imhasin, Dmitry V. Ionov, Farahnaz Khosrawi, Sergey I. Osipov, Maximilian Reuter, Matthias Schneider, and Thorsten Warneke
Atmos. Meas. Tech., 15, 2199–2229, https://doi.org/10.5194/amt-15-2199-2022, https://doi.org/10.5194/amt-15-2199-2022, 2022
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Satellite and ground-based observations at high latitudes are much sparser than at low or mid latitudes, which makes direct coincident comparisons between remote-sensing observations more difficult. Therefore, a method of scaling continuous CAMS model data to the ground-based observations is developed and used for creating virtual COCCON observations. These adjusted CAMS data are then used for satellite inter-comparison, showing good agreement in both Peterhof and Yekaterinburg cities.
Omaira Elena García, Esther Sanromá, Frank Hase, Matthias Schneider, Sergio Fabián León-Luis, Thomas Blumenstock, Eliezer Sepúlveda, Carlos Torres, Natalia Prats, Alberto Redondas, and Virgilio Carreño
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2022-44, https://doi.org/10.5194/amt-2022-44, 2022
Preprint under review for AMT
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Retrieving high-precision concentrations of atmospheric trace gases from FTIR (Fourier Transform Infrared) spectrometry requires a precise knowledge of the instrumental performance. In this context, this paper examines the impact on the ozone (O3) retrievals of several approaches used to characterise the Instrumental Line Shape (ILS) function of ground-based FTIR spectrometers within NDACC (Network for the Detection of Atmospheric Composition Change).
Sören Johansson, Gerald Wetzel, Felix Friedl-Vallon, Norbert Glatthor, Michael Höpfner, Anne Kleinert, Tom Neubert, Björn-Martin Sinnhuber, and Jörn Ungermann
Atmos. Chem. Phys., 22, 3675–3691, https://doi.org/10.5194/acp-22-3675-2022, https://doi.org/10.5194/acp-22-3675-2022, 2022
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We present GLORIA airborne cross sections of PAN, C2H6, HCOOH, CH3OH, and C2H4 in the South Atlantic UTLS in September/October 2019. Filamentary structures and a large plume were observed. Backward trajectories indicate that measured pollutants come from South America and central Africa. Comparisons to CAMS show structural agreement of the measured distributions. PAN absolute VMRs agree with the GLORIA measurements, C2H6 and HCOOH are simulated too low, and CH3OH and C2H4 are too high.
Thomas von Clarmann, Steven Compernolle, and Frank Hase
Atmos. Meas. Tech., 15, 1145–1157, https://doi.org/10.5194/amt-15-1145-2022, https://doi.org/10.5194/amt-15-1145-2022, 2022
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Contrary to the claims put forward in
Evaluation of measurement data – Guide to the expression of uncertainty in measurementissued by the JCGM, the error concept and the uncertainty concept are the same. Arguments in favor of the contrary were found not to be compelling. Neither was any evidence presented that
errorsand
uncertaintiesdefine a different relation between the measured and true values, nor is a Bayesian concept beyond the mere subjective probability referred to.
Florian Haenel, Wolfgang Woiwode, Jennifer Buchmüller, Felix Friedl-Vallon, Michael Höpfner, Sören Johansson, Farahnaz Khosrawi, Oliver Kirner, Anne Kleinert, Hermann Oelhaf, Johannes Orphal, Roland Ruhnke, Björn-Martin Sinnhuber, Jörn Ungermann, Michael Weimer, and Peter Braesicke
Atmos. Chem. Phys., 22, 2843–2870, https://doi.org/10.5194/acp-22-2843-2022, https://doi.org/10.5194/acp-22-2843-2022, 2022
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We compare remote sensing observations of H2O, O3, HNO3 and clouds in the upper troposphere–lowermost stratosphere during an Arctic winter long-range research flight with simulations by two different state-of-the-art model systems. We find good agreement for dynamical structures, trace gas distributions and clouds. We investigate model biases and sensitivities, with the goal of aiding model development and improving our understanding of processes in the upper troposphere–lowermost stratosphere.
Steffen Beirle, Christian Borger, Steffen Dörner, Vinod Kumar, and Thomas Wagner
Atmos. Meas. Tech., 15, 987–1006, https://doi.org/10.5194/amt-15-987-2022, https://doi.org/10.5194/amt-15-987-2022, 2022
Short summary
Short summary
We present a formalism that relates the vertical column density (VCD) of the oxygen collision complex O4 to surface values of temperature and pressure, based on physical laws. In addition, we propose an empirical modification which also accounts for surface relative humidity (RH). This allows for simple and quick but still accurate calculation of the O4 VCD without the need for constructing full vertical profiles, which is expected to be useful in particular for MAX-DOAS applications.
Christian Borger, Steffen Beirle, and Thomas Wagner
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-149, https://doi.org/10.5194/acp-2022-149, 2022
Preprint under review for ACP
Short summary
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In this study, we analyze trends of total column water vapour (TCWV) using multiple years of satellite observations and find on global average an increase in the TCWV amount by about 0.24 % per year. Further investigations of the hydrological cycle reveal that the assumption of temporally invariant relative humidity is not always fulfilled and that its responses to global warming are 2 to 4 times higher than theoretically expected or previously reported values.
Matthias Schneider, Benjamin Ertl, Christopher J. Diekmann, Farahnaz Khosrawi, Andreas Weber, Frank Hase, Michael Höpfner, Omaira E. García, Eliezer Sepúlveda, and Douglas Kinnison
Earth Syst. Sci. Data, 14, 709–742, https://doi.org/10.5194/essd-14-709-2022, https://doi.org/10.5194/essd-14-709-2022, 2022
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We present atmospheric H2O, HDO / H2O ratio, N2O, CH4, and HNO3 data generated by the MUSICA IASI processor using thermal nadir spectra measured by the IASI satellite instrument. The data have global daily coverage and are available for the period between October 2014 and June 2021. Multiple possibilities of data reuse are offered by providing each individual data product together with information about retrieval settings and the products' uncertainty and vertical representativeness.
Qiansi Tu, Matthias Schneider, Frank Hase, Farahnaz Khosrawi, Benjamin Ertl, Jaroslaw Necki, Darko Dubravica, Christopher J. Diekmann, Thomas Blumenstock, and Dianjun Fang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-41, https://doi.org/10.5194/acp-2022-41, 2022
Revised manuscript accepted for ACP
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Three-year satellite observations and high-resolution model forecast of XCH4 are used to derive CH4 emissions in the USCB region, Poland, a region of intensive coal mining activities. The wind-assigned anomalies for two opposite wind directions are calculate and the estimated emission rates are very close to the inventories and in reasonable agreement to the previous studies. Our method is quite robust and can be served as a simple method to estimate CH4 or CO2 emissions for other regions.
Thomas E. Taylor, Christopher W. O'Dell, David Crisp, Akhiko Kuze, Hannakaisa Lindqvist, Paul O. Wennberg, Abhishek Chatterjee, Michael Gunson, Annmarie Eldering, Brendan Fisher, Matthäus Kiel, Robert R. Nelson, Aronne Merrelli, Greg Osterman, Frédéric Chevallier, Paul I. Palmer, Liang Feng, Nicholas M. Deutscher, Manvendra K. Dubey, Dietrich G. Feist, Omaira E. García, David W. T. Griffith, Frank Hase, Laura T. Iraci, Rigel Kivi, Cheng Liu, Martine De Mazière, Isamu Morino, Justus Notholt, Young-Suk Oh, Hirofumi Ohyama, David F. Pollard, Markus Rettinger, Matthias Schneider, Coleen M. Roehl, Mahesh Kumar Sha, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Yao Té, Voltaire A. Velazco, Mihalis Vrekoussis, Thorsten Warneke, and Debra Wunch
Earth Syst. Sci. Data, 14, 325–360, https://doi.org/10.5194/essd-14-325-2022, https://doi.org/10.5194/essd-14-325-2022, 2022
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We provide an analysis of an 11-year record of atmospheric carbon dioxide (CO2) concentrations derived using an optimal estimation retrieval algorithm on measurements made by the GOSAT satellite. The new product (version 9) shows improvement over the previous version (v7.3) as evaluated against independent estimates of CO2 from ground-based sensors and atmospheric inversion systems. We also compare the new GOSAT CO2 values to collocated estimates from NASA's Orbiting Carbon Observatory-2.
Adriana Bailey, Franziska Aemisegger, Leonie Villiger, Sebastian A. Los, Gilles Reverdin, Estefanía Quiñones Meléndez, Claudia Acquistapace, Dariusz B. Baranowski, Tobias Böck, Sandrine Bony, Tobias Bordsdorff, Derek Coffman, Simon P. de Szoeke, Christopher J. Diekmann, Marina Dütsch, Benjamin Ertl, Joseph Galewsky, Dean Henze, Przemyslaw Makuch, David Noone, Patricia K. Quinn, Michael Rösch, Andreas Schneider, Matthias Schneider, Sabrina Speich, Bjorn Stevens, and Elizabeth Thompson
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2022-3, https://doi.org/10.5194/essd-2022-3, 2022
Preprint under review for ESSD
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One of the novel ways EUREC4A set out to investigate trade wind clouds and their coupling to the large-scale circulation was through an extensive network of isotopic measurements in water vapor, precipitation, and seawater. Samples were taken from the island of Barbados, from aboard two aircraft, and from aboard four ships. This paper describes the full collection of EUREC4A isotopic in situ data and guides readers to complementary remotely sensed water vapor isotope ratios.
Christoph von Rohden, Michael Sommer, Tatjana Naebert, Vasyl Motuz, and Ruud J. Dirksen
Atmos. Meas. Tech., 15, 383–405, https://doi.org/10.5194/amt-15-383-2022, https://doi.org/10.5194/amt-15-383-2022, 2022
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Heating by solar radiation is the dominant error source for daytime temperature measurements by radiosondes. This paper describes a new laboratory setup (SISTER) to characterise this radiation error for pressures and ventilation speeds that are typical for the conditions between the surface and 35 km altitude. This characterisation is the basis for the radiation correction that is applied in the GRUAN data processing for the RS41 radiosonde. The GRUAN data product is compared to that of Vaisala.
Tobias Küchler, Stefan Noël, Heinrich Bovensmann, John Philip Burrows, Thomas Wagner, Christian Borger, Tobias Borsdorff, and Andreas Schneider
Atmos. Meas. Tech., 15, 297–320, https://doi.org/10.5194/amt-15-297-2022, https://doi.org/10.5194/amt-15-297-2022, 2022
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We applied the air-mass-corrected differential optical absorption spectroscopy (AMC-DOAS) method to derive total column water vapour (TCWV) from Sentinel-5P measurements and compared it to independent data sets. The correlation coefficients of typically more than 0.9 and the small deviations up to 2.5 kg m−2 reveal good agreement between our data product and other TCWV data sets. In particular for the different Sentinel-5P water vapour products, the deviations are around 1 kg m−2.
Bruce Ingleby, Martin Motl, Graeme Marlton, David Edwards, Michael Sommer, Christoph von Rohden, Holger Vömel, and Hannu Jauhiainen
Atmos. Meas. Tech., 15, 165–183, https://doi.org/10.5194/amt-15-165-2022, https://doi.org/10.5194/amt-15-165-2022, 2022
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Radiosonde descent data could provide extra profiles of the atmosphere for forecasting and other uses. Descent data from Vaisala RS41 radiosondes have been compared with the ascent profiles and with ECMWF short-range forecasts. The agreement is mostly good. The descent rate is very variable and high descent rates cause temperature biases, especially at upper levels. Ascent winds are affected by pendulum motion; on average, the descent winds are smoother.
Qiansi Tu, Frank Hase, Matthias Schneider, Omaira García, Thomas Blumenstock, Tobias Borsdorff, Matthias Frey, Farahnaz Khosrawi, Alba Lorente, Carlos Alberti, Juan J. Bustos, André Butz, Virgilio Carreño, Emilio Cuevas, Roger Curcoll, Christopher J. Diekmann, Darko Dubravica, Benjamin Ertl, Carme Estruch, Sergio Fabián León-Luis, Carlos Marrero, Josep-Anton Morgui, Ramón Ramos, Christian Scharun, Carsten Schneider, Eliezer Sepúlveda, Carlos Toledano, and Carlos Torres
Atmos. Chem. Phys., 22, 295–317, https://doi.org/10.5194/acp-22-295-2022, https://doi.org/10.5194/acp-22-295-2022, 2022
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We use different methane ground- and space-based remote sensing data sets for investigating the emission strength of three waste disposal sites close to Madrid. We present a method that uses wind-assigned anomalies for deriving emission strengths from satellite data and estimate their uncertainty to 9–14 %. The emission strengths estimated from the remote sensing data sets are significantly larger than the values published in the official register.
Jānis Puķīte, Christian Borger, Steffen Dörner, Myojeong Gu, and Thomas Wagner
Atmos. Chem. Phys., 22, 245–272, https://doi.org/10.5194/acp-22-245-2022, https://doi.org/10.5194/acp-22-245-2022, 2022
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Chlorine dioxide (OClO) is an indicator for chlorine activation. New OClO data by TROPOMI (S5P) are interpreted in a meteorological context and related to CALIOP PSC observations. We report very high OClO levels for the northern hemispheric winter 2019/20 with an extraordinarily long period with a stable polar vortex. A minor stratospheric warming in the Southern Hemisphere was also observed in September 2019, where usual OClO values rapidly deactivated 1–2 weeks earlier.
Michael Höpfner, Oliver Kirner, Gerald Wetzel, Björn-Martin Sinnhuber, Florian Haenel, Sören Johansson, Johannes Orphal, Roland Ruhnke, Gabriele Stiller, and Thomas von Clarmann
Atmos. Chem. Phys., 21, 18433–18464, https://doi.org/10.5194/acp-21-18433-2021, https://doi.org/10.5194/acp-21-18433-2021, 2021
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BrONO2 is an important reservoir gas for inorganic stratospheric bromine linked to the chemical cycles of stratospheric ozone depletion. Presently infrared limb sounding is the only way to measure BrONO2 in the atmosphere. We provide global distributions of BrONO2 derived from MIPAS observations 2002–2012. Comparisons with EMAC atmospheric modelling show an overall agreement and enable us to derive an independent estimate of stratospheric bromine of 21.2±1.4pptv based on the BrONO2 measurements.
Christian Borger, Steffen Beirle, and Thomas Wagner
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2021-319, https://doi.org/10.5194/essd-2021-319, 2021
Preprint under review for ESSD
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This study presents a long-term data set of monthly mean total column water vapour (TCWV) based on measurements of the Ozone Monitoring Instrument (OMI) covering the time range from January 2005 to December 2020. We describe how the TCWV values are retrieved from UV-vis satellite spectra and demonstrate that the OMI TCWV data set is in good agreement to various different reference data sets. Moreover, we also show that it fulfills typical stability requirements for climate data records.
Jānis Puķīte, Christian Borger, Steffen Dörner, Myojeong Gu, Udo Frieß, Andreas Carlos Meier, Carl-Fredrik Enell, Uwe Raffalski, Andreas Richter, and Thomas Wagner
Atmos. Meas. Tech., 14, 7595–7625, https://doi.org/10.5194/amt-14-7595-2021, https://doi.org/10.5194/amt-14-7595-2021, 2021
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Chlorine dioxide (OClO) is used as an indicator for chlorine activation. We present a new differential optical absorption spectroscopy retrieval algorithm for OClO from measurements of TROPOMI on the Sentinel-5P satellite. To achieve a substantially improved accuracy for the weak absorber OClO, we consider several additional fit parameters accounting for various higher-order spectral effects. The retrieved OClO slant column densities are compared with ground-based zenith sky measurements.
Nicole Jacobs, William R. Simpson, Kelly A. Graham, Christopher Holmes, Frank Hase, Thomas Blumenstock, Qiansi Tu, Matthias Frey, Manvendra K. Dubey, Harrison A. Parker, Debra Wunch, Rigel Kivi, Pauli Heikkinen, Justus Notholt, Christof Petri, and Thorsten Warneke
Atmos. Chem. Phys., 21, 16661–16687, https://doi.org/10.5194/acp-21-16661-2021, https://doi.org/10.5194/acp-21-16661-2021, 2021
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Spatial patterns of carbon dioxide seasonal cycle amplitude and summer drawdown timing derived from the OCO-2 satellite over northern high latitudes agree well with corresponding estimates from two models. The Asian boreal forest is anomalous with the largest amplitude and earliest seasonal drawdown. Modeled land contact tracers suggest that accumulated CO2 exchanges during atmospheric transport play a major role in shaping carbon dioxide seasonality in northern high-latitude regions.
Christopher J. Diekmann, Matthias Schneider, Benjamin Ertl, Frank Hase, Omaira García, Farahnaz Khosrawi, Eliezer Sepúlveda, Peter Knippertz, and Peter Braesicke
Earth Syst. Sci. Data, 13, 5273–5292, https://doi.org/10.5194/essd-13-5273-2021, https://doi.org/10.5194/essd-13-5273-2021, 2021
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The joint analysis of different stable water isotopes in water vapour is a powerful tool for investigating atmospheric moisture pathways. This paper presents a novel global and multi-annual dataset of H2O and HDO in mid-tropospheric water vapour by using data from the satellite sensor Metop/IASI. Due to its unique combination of coverage and resolution in space and time, this dataset is highly promising for studying the hydrological cycle and its representation in weather and climate models.
Fabienne Dahinden, Franziska Aemisegger, Heini Wernli, Matthias Schneider, Christopher J. Diekmann, Benjamin Ertl, Peter Knippertz, Martin Werner, and Stephan Pfahl
Atmos. Chem. Phys., 21, 16319–16347, https://doi.org/10.5194/acp-21-16319-2021, https://doi.org/10.5194/acp-21-16319-2021, 2021
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We use high-resolution numerical isotope modelling and Lagrangian backward trajectories to identify moisture transport pathways and governing physical and dynamical processes that affect the free-tropospheric humidity and isotopic variability over the eastern subtropical North Atlantic. Furthermore, we conduct a thorough isotope modelling validation with aircraft and remote-sensing observations of water vapour isotopes.
Omaira E. García, Matthias Schneider, Eliezer Sepúlveda, Frank Hase, Thomas Blumenstock, Emilio Cuevas, Ramón Ramos, Jochen Gross, Sabine Barthlott, Amelie N. Röhling, Esther Sanromá, Yenny González, Ángel J. Gómez-Peláez, Mónica Navarro-Comas, Olga Puentedura, Margarita Yela, Alberto Redondas, Virgilio Carreño, Sergio F. León-Luis, Enrique Reyes, Rosa D. García, Pedro P. Rivas, Pedro M. Romero-Campos, Carlos Torres, Natalia Prats, Miguel Hernández, and César López
Atmos. Chem. Phys., 21, 15519–15554, https://doi.org/10.5194/acp-21-15519-2021, https://doi.org/10.5194/acp-21-15519-2021, 2021
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This paper analyses the potential of ground-based Fourier transform infrared (FTIR) solar observations to monitor atmospheric gaseous composition and investigate multiple climate processes. To this end, this work reviews the FTIR programme of one of most relevant ground-based FTIR stations at a global scale, the subtropical Izaña Observatory (IZO, Spain), going over its history during its first 20 years of operation (1999–2018) and exploring its great value for long-term climate research.
Mahesh Kumar Sha, Bavo Langerock, Jean-François L. Blavier, Thomas Blumenstock, Tobias Borsdorff, Matthias Buschmann, Angelika Dehn, Martine De Mazière, Nicholas M. Deutscher, Dietrich G. Feist, Omaira E. García, David W. T. Griffith, Michel Grutter, James W. Hannigan, Frank Hase, Pauli Heikkinen, Christian Hermans, Laura T. Iraci, Pascal Jeseck, Nicholas Jones, Rigel Kivi, Nicolas Kumps, Jochen Landgraf, Alba Lorente, Emmanuel Mahieu, Maria V. Makarova, Johan Mellqvist, Jean-Marc Metzger, Isamu Morino, Tomoo Nagahama, Justus Notholt, Hirofumi Ohyama, Ivan Ortega, Mathias Palm, Christof Petri, David F. Pollard, Markus Rettinger, John Robinson, Sébastien Roche, Coleen M. Roehl, Amelie N. Röhling, Constantina Rousogenous, Matthias Schneider, Kei Shiomi, Dan Smale, Wolfgang Stremme, Kimberly Strong, Ralf Sussmann, Yao Té, Osamu Uchino, Voltaire A. Velazco, Corinne Vigouroux, Mihalis Vrekoussis, Pucai Wang, Thorsten Warneke, Tyler Wizenberg, Debra Wunch, Shoma Yamanouchi, Yang Yang, and Minqiang Zhou
Atmos. Meas. Tech., 14, 6249–6304, https://doi.org/10.5194/amt-14-6249-2021, https://doi.org/10.5194/amt-14-6249-2021, 2021
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This paper presents, for the first time, Sentinel-5 Precursor methane and carbon monoxide validation results covering a period from November 2017 to September 2020. For this study, we used global TCCON and NDACC-IRWG network data covering a wide range of atmospheric and surface conditions across different terrains. We also show the influence of a priori alignment, smoothing uncertainties and the sensitivity of the validation results towards the application of advanced co-location criteria.
Taylor S. Jones, Jonathan E. Franklin, Jia Chen, Florian Dietrich, Kristian D. Hajny, Johannes C. Paetzold, Adrian Wenzel, Conor Gately, Elaine Gottlieb, Harrison Parker, Manvendra Dubey, Frank Hase, Paul B. Shepson, Levi H. Mielke, and Steven C. Wofsy
Atmos. Chem. Phys., 21, 13131–13147, https://doi.org/10.5194/acp-21-13131-2021, https://doi.org/10.5194/acp-21-13131-2021, 2021
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Methane emissions from leaks in natural gas pipes are often a large source in urban areas, but they are difficult to measure on a city-wide scale. Here we use an array of innovative methane sensors distributed around the city of Indianapolis and a new method of combining their data with an atmospheric model to accurately determine the magnitude of these emissions, which are about 70 % larger than predicted. This method can serve as a framework for cities trying to account for their emissions.
Matthias M. Frey, Frank Hase, Thomas Blumenstock, Darko Dubravica, Jochen Groß, Frank Göttsche, Martin Handjaba, Petrus Amadhila, Roland Mushi, Isamu Morino, Kei Shiomi, Mahesh Kumar Sha, Martine de Mazière, and David F. Pollard
Atmos. Meas. Tech., 14, 5887–5911, https://doi.org/10.5194/amt-14-5887-2021, https://doi.org/10.5194/amt-14-5887-2021, 2021
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In this study, we present measurements of carbon dioxide, methane and carbon monoxide from a recently established site in Gobabeb, Namibia. Gobabeb is the first site observing these gases on the African mainland and improves the global coverage of measurement sites. Gobabeb is a hyperarid desert site, offering unique characteristics. Measurements started 2015 as part of the COllaborative Carbon Column Observing Network. We compare our results with other datasets and find a good agreement.
Jennifer Schallock, Christoph Brühl, Christine Bingen, Michael Höpfner, Landon Rieger, and Jos Lelieveld
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-654, https://doi.org/10.5194/acp-2021-654, 2021
Preprint under review for ACP
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This paper presents model simulations of stratospheric aerosols with a focus on explosive volcanic eruptions. Using occulation and limb-based satellite instruments with vertical profiles of sulfur dioxide and aerosol extinction, we characterised the influence of volcanic aerosols for the period between 1990–2019. We established a volcanic sulfur emission inventory that includes more than 500 eruptions. Our results show that also smaller eruptions can contribute to the stratospheric aerosol layer.
Rebecca D. Kutzner, Juan Cuesta, Pascale Chelin, Jean-Eudes Petit, Mokhtar Ray, Xavier Landsheere, Benoît Tournadre, Jean-Charles Dupont, Amandine Rosso, Frank Hase, Johannes Orphal, and Matthias Beekmann
Atmos. Chem. Phys., 21, 12091–12111, https://doi.org/10.5194/acp-21-12091-2021, https://doi.org/10.5194/acp-21-12091-2021, 2021
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Our work investigates the diurnal evolution of atmospheric ammonia concentrations during a major pollution event. It analyses it in regard of both chemical (gas–particle conversion) and physical (vertical mixing, meteorology) processes in the atmosphere. These mechanisms are key for understanding the evolution of the physicochemical state of the atmosphere; therefore, it clearly fits into the scope of Atmospheric Chemistry and Physics.
Farahnaz Khosrawi, Kinya Toride, Kei Yoshimura, Christopher J. Diekmann, Benjamin Ertl, Frank Hase, and Matthias Schneider
Weather Clim. Dynam. Discuss., https://doi.org/10.5194/wcd-2021-49, https://doi.org/10.5194/wcd-2021-49, 2021
Revised manuscript not accepted
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We assess with an Observation System Simulation Experiment the potential of mid-tropospheric water isotopologue data for constraining uncertainties in meteorological analysis fields in the tropics. Our assimilation experiments indicate that isotopologue observations have the potential to reduce the uncertainties of diabatic heating rates and meteorological variables in the tropics and in consequence offer potential for improving meteorological analysis in the tropical regions.
Dmitry V. Ionov, Maria V. Makarova, Frank Hase, Stefani C. Foka, Vladimir S. Kostsov, Carlos Alberti, Thomas Blumenstock, Thorsten Warneke, and Yana A. Virolainen
Atmos. Chem. Phys., 21, 10939–10963, https://doi.org/10.5194/acp-21-10939-2021, https://doi.org/10.5194/acp-21-10939-2021, 2021
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Megacities are a significant source of emissions of various substances in the atmosphere, including carbon dioxide, which is the most important anthropogenic greenhouse gas. In 2019–2020, the Emission Monitoring Mobile Experiment was carried out in St Petersburg, which is the second-largest industrial city in Russia. The results of this experiment, coupled with numerical modelling, helped to estimate the amount of CO2 emitted by the city. This value was twice as high as predicted.
Ilya Stanevich, Dylan B. A. Jones, Kimberly Strong, Martin Keller, Daven K. Henze, Robert J. Parker, Hartmut Boesch, Debra Wunch, Justus Notholt, Christof Petri, Thorsten Warneke, Ralf Sussmann, Matthias Schneider, Frank Hase, Rigel Kivi, Nicholas M. Deutscher, Voltaire A. Velazco, Kaley A. Walker, and Feng Deng
Atmos. Chem. Phys., 21, 9545–9572, https://doi.org/10.5194/acp-21-9545-2021, https://doi.org/10.5194/acp-21-9545-2021, 2021
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We explore the utility of a weak-constraint (WC) four-dimensional variational (4D-Var) data assimilation scheme for mitigating systematic errors in methane simulation in the GEOS-Chem model. We use data from the Greenhouse Gases Observing Satellite (GOSAT) and show that, compared to the traditional 4D-Var approach, the WC scheme improves the agreement between the model and independent observations. We find that the WC corrections to the model provide insight into the source of the errors.
Matthieu Dogniaux, Cyril Crevoisier, Raymond Armante, Virginie Capelle, Thibault Delahaye, Vincent Cassé, Martine De Mazière, Nicholas M. Deutscher, Dietrich G. Feist, Omaira E. Garcia, David W. T. Griffith, Frank Hase, Laura T. Iraci, Rigel Kivi, Isamu Morino, Justus Notholt, David F. Pollard, Coleen M. Roehl, Kei Shiomi, Kimberly Strong, Yao Té, Voltaire A. Velazco, and Thorsten Warneke
Atmos. Meas. Tech., 14, 4689–4706, https://doi.org/10.5194/amt-14-4689-2021, https://doi.org/10.5194/amt-14-4689-2021, 2021
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We present the Adaptable 4A Inversion (5AI), an implementation of the optimal estimation (OE) algorithm, relying on the Automatized Atmospheric Absorption Atlas (4A/OP) radiative transfer model, that enables the retrieval of greenhouse gas atmospheric weighted columns from infrared measurements. It is tested on a sample of Orbiting Carbon Observatory-2 observations, and its results satisfactorily compare to several reference products, thus showing the reliability of 5AI OE implementation.
Steffen Beirle, Christian Borger, Steffen Dörner, Henk Eskes, Vinod Kumar, Adrianus de Laat, and Thomas Wagner
Earth Syst. Sci. Data, 13, 2995–3012, https://doi.org/10.5194/essd-13-2995-2021, https://doi.org/10.5194/essd-13-2995-2021, 2021
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A catalog of point sources of nitrogen oxides was created using satellite observations of NO2. Key for the identification of point sources was the divergence, i.e., the difference between upwind and downwind levels of NO2.
The catalog lists 451 locations, of which 242 could be automatically matched to power plants. Other point sources are metal smelters, cement plants, or industrial areas. The catalog thus allows checking and improving of existing emission inventories.
Holger Sihler, Steffen Beirle, Steffen Dörner, Marloes Gutenstein-Penning de Vries, Christoph Hörmann, Christian Borger, Simon Warnach, and Thomas Wagner
Atmos. Meas. Tech., 14, 3989–4031, https://doi.org/10.5194/amt-14-3989-2021, https://doi.org/10.5194/amt-14-3989-2021, 2021
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MICRU is an algorithm for the retrieval of effective cloud fractions (CFs) from satellite measurements. CFs describe the amount of clouds, which have a significant impact on the vertical sensitivity profile of trace gases like NO2 and HCHO. MICRU retrieves small CFs with an accuracy of 0.04 over the entire satellite swath. It features an empirical surface reflectivity model accounting for physical anisotropy (BRDF, sun glitter) and instrumental effects. MICRU is also applicable to imager data.
Gerald Wetzel, Felix Friedl-Vallon, Norbert Glatthor, Jens-Uwe Grooß, Thomas Gulde, Michael Höpfner, Sören Johansson, Farahnaz Khosrawi, Oliver Kirner, Anne Kleinert, Erik Kretschmer, Guido Maucher, Hans Nordmeyer, Hermann Oelhaf, Johannes Orphal, Christof Piesch, Björn-Martin Sinnhuber, Jörn Ungermann, and Bärbel Vogel
Atmos. Chem. Phys., 21, 8213–8232, https://doi.org/10.5194/acp-21-8213-2021, https://doi.org/10.5194/acp-21-8213-2021, 2021
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Measurements of the pollutants C2H6, C2H2, HCOOH, and PAN were performed in the North Atlantic UTLS region with the airborne limb imager GLORIA in 2017. Enhanced amounts of these species were detected in the upper troposphere and even in the lowermost stratosphere (PAN). Main sources of these gases are forest fires in North America and anthropogenic pollution in South Asia. Simulations of EMAC and CAMS are qualitatively able to reproduce the measured data but underestimate the absolute amounts.
Stefan Noël, Maximilian Reuter, Michael Buchwitz, Jakob Borchardt, Michael Hilker, Heinrich Bovensmann, John P. Burrows, Antonio Di Noia, Hiroshi Suto, Yukio Yoshida, Matthias Buschmann, Nicholas M. Deutscher, Dietrich G. Feist, David W. T. Griffith, Frank Hase, Rigel Kivi, Isamu Morino, Justus Notholt, Hirofumi Ohyama, Christof Petri, James R. Podolske, David F. Pollard, Mahesh Kumar Sha, Kei Shiomi, Ralf Sussmann, Yao Té, Voltaire A. Velazco, and Thorsten Warneke
Atmos. Meas. Tech., 14, 3837–3869, https://doi.org/10.5194/amt-14-3837-2021, https://doi.org/10.5194/amt-14-3837-2021, 2021
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We present the first GOSAT and GOSAT-2 XCO2 data derived with the FOCAL retrieval algorithm. Comparisons of the GOSAT-FOCAL product with other data reveal long-term agreement within about 1 ppm over 1 decade, differences in seasonal variations of about 0.5 ppm, and a mean regional bias to ground-based TCCON data of 0.56 ppm with a mean scatter of 1.89 ppm. GOSAT-2-FOCAL data are preliminary only, but first comparisons show that they compare well with the GOSAT-FOCAL results and TCCON.
Irene Bartolome Garcia, Reinhold Spang, Jörn Ungermann, Sabine Griessbach, Martina Krämer, Michael Höpfner, and Martin Riese
Atmos. Meas. Tech., 14, 3153–3168, https://doi.org/10.5194/amt-14-3153-2021, https://doi.org/10.5194/amt-14-3153-2021, 2021
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Cirrus clouds contribute to the general radiation budget of the Earth. Measuring optically thin clouds is challenging but the IR limb sounder GLORIA possesses the necessary technical characteristics to make it possible. This study analyses data from the WISE campaign obtained with GLORIA. We developed a cloud detection method and derived characteristics of the observed cirrus-like cloud top, cloud bottom or position with respect to the tropopause.
Thomas Wagner, Steffen Beirle, Steffen Dörner, Christian Borger, and Roeland Van Malderen
Atmos. Chem. Phys., 21, 5315–5353, https://doi.org/10.5194/acp-21-5315-2021, https://doi.org/10.5194/acp-21-5315-2021, 2021
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A global long-term (1995–2015) data set of total column water vapour (TCWV) derived from satellite observations is used to quantify the influence of teleconnections. Based on a newly developed empirical method more than 40 teleconnection indices are significantly detected in our global TCWV data set. After orthogonalisation, only 20 indices are left significant. The global distribution of the cumulative influence of teleconnection indices is strongest in the tropics and high latitudes.
Robert Wagner, Baptiste Testa, Michael Höpfner, Alexei Kiselev, Ottmar Möhler, Harald Saathoff, Jörn Ungermann, and Thomas Leisner
Atmos. Meas. Tech., 14, 1977–1991, https://doi.org/10.5194/amt-14-1977-2021, https://doi.org/10.5194/amt-14-1977-2021, 2021
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During the Asian summer monsoon period, air pollutants are transported from layers near the ground to high altitudes of 13 to 18 km in the atmosphere. Infrared measurements have shown that particles composed of solid ammonium nitrate are a major part of these pollutants. To enable the quantitative analysis of the infrared spectra, we have determined for the first time accurate optical constants of ammonium nitrate for the low-temperature conditions of the upper atmosphere.
Qiansi Tu, Frank Hase, Thomas Blumenstock, Matthias Schneider, Andreas Schneider, Rigel Kivi, Pauli Heikkinen, Benjamin Ertl, Christopher Diekmann, Farahnaz Khosrawi, Michael Sommer, Tobias Borsdorff, and Uwe Raffalski
Atmos. Meas. Tech., 14, 1993–2011, https://doi.org/10.5194/amt-14-1993-2021, https://doi.org/10.5194/amt-14-1993-2021, 2021
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We compare column-averaged dry-air mole fractions of water vapor (XH2O) retrievals from the COllaborative Carbon Column Observing Network (COCCON) with two co-located ground-based spectrometers as references at two boreal sites. Our study supports the assumption that COCCON also delivers a well-characterized XH2O data product. This is the first published study applying COCCON for MUSICA IASI and TROPOMI validation.
Matthias Schneider, Benjamin Ertl, Christopher J. Diekmann, Farahnaz Khosrawi, Amelie N. Röhling, Frank Hase, Darko Dubravica, Omaira E. García, Eliezer Sepúlveda, Tobias Borsdorff, Jochen Landgraf, Alba Lorente, Huilin Chen, Rigel Kivi, Thomas Laemmel, Michel Ramonet, Cyril Crevoisier, Jérome Pernin, Martin Steinbacher, Frank Meinhardt, Nicholas M. Deutscher, David W. T. Griffith, Voltaire A. Velazco, and David F. Pollard
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2021-31, https://doi.org/10.5194/amt-2021-31, 2021
Revised manuscript accepted for AMT
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We present a computationally very efficient method for the synergetic use of different remote sensing data sets. We apply the method to IASI vertical profile and TROPOMI total column space borne methane observations and thus gain sensitivity for the tropospheric methane partial columns, which is not achievable by the individual use of TROPOMI and IASI. These synergetic effects are evaluated theoretically and by inter-comparisons to independent references of TCCON, AirCore, and GAW.
Thomas Blumenstock, Frank Hase, Axel Keens, Denis Czurlok, Orfeo Colebatch, Omaira Garcia, David W. T. Griffith, Michel Grutter, James W. Hannigan, Pauli Heikkinen, Pascal Jeseck, Nicholas Jones, Rigel Kivi, Erik Lutsch, Maria Makarova, Hamud K. Imhasin, Johan Mellqvist, Isamu Morino, Tomoo Nagahama, Justus Notholt, Ivan Ortega, Mathias Palm, Uwe Raffalski, Markus Rettinger, John Robinson, Matthias Schneider, Christian Servais, Dan Smale, Wolfgang Stremme, Kimberly Strong, Ralf Sussmann, Yao Té, and Voltaire A. Velazco
Atmos. Meas. Tech., 14, 1239–1252, https://doi.org/10.5194/amt-14-1239-2021, https://doi.org/10.5194/amt-14-1239-2021, 2021
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This study investigates the level of channeling (optical resonances) of each FTIR spectrometer within the Network for the Detection of Atmospheric Composition Change (NDACC). Since the air gap of the beam splitter is a significant source of channeling, we propose new beam splitters with an increased wedge of the air gap. This study shows the potential for reducing channeling in the FTIR spectrometers operated by the NDACC, thereby increasing the quality of recorded spectra across the network.
Maria V. Makarova, Carlos Alberti, Dmitry V. Ionov, Frank Hase, Stefani C. Foka, Thomas Blumenstock, Thorsten Warneke, Yana A. Virolainen, Vladimir S. Kostsov, Matthias Frey, Anatoly V. Poberovskii, Yuri M. Timofeyev, Nina N. Paramonova, Kristina A. Volkova, Nikita A. Zaitsev, Egor Y. Biryukov, Sergey I. Osipov, Boris K. Makarov, Alexander V. Polyakov, Viktor M. Ivakhov, Hamud Kh. Imhasin, and Eugene F. Mikhailov
Atmos. Meas. Tech., 14, 1047–1073, https://doi.org/10.5194/amt-14-1047-2021, https://doi.org/10.5194/amt-14-1047-2021, 2021
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Fundamental understanding of the major processes driving climate change is a key problem which is to be solved, not only on a global but also on a regional scale. The Emission Monitoring Mobile Experiment (EMME) carried out in 2019 with two portable Bruker EM27/SUN spectrometers as core instruments provided new information on the emissions of greenhouse (CO2, CH4) and reactive (CO, NOx) gases from St. Petersburg (Russia), which is the largest northern megacity with a population of 5 million.
Marvin Knapp, Ralph Kleinschek, Frank Hase, Anna Agustí-Panareda, Antje Inness, Jérôme Barré, Jochen Landgraf, Tobias Borsdorff, Stefan Kinne, and André Butz
Earth Syst. Sci. Data, 13, 199–211, https://doi.org/10.5194/essd-13-199-2021, https://doi.org/10.5194/essd-13-199-2021, 2021
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We developed a shipborne variant of a remote sensing spectrometer for direct sunlight measurements of column-averaged atmospheric mixing ratios of carbon dioxide, methane, and carbon monoxide. The instrument was deployed on the research vessel Sonne during a longitudinal transect over the Pacific during June 2019. The campaign yielded more than 32 000 observations which compare excellently to atmospheric composition data from a state-of-the-art model (CAMS) and satellite observations (TROPOMI).
Alba Lorente, Tobias Borsdorff, Andre Butz, Otto Hasekamp, Joost aan de Brugh, Andreas Schneider, Lianghai Wu, Frank Hase, Rigel Kivi, Debra Wunch, David F. Pollard, Kei Shiomi, Nicholas M. Deutscher, Voltaire A. Velazco, Coleen M. Roehl, Paul O. Wennberg, Thorsten Warneke, and Jochen Landgraf
Atmos. Meas. Tech., 14, 665–684, https://doi.org/10.5194/amt-14-665-2021, https://doi.org/10.5194/amt-14-665-2021, 2021
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TROPOMI aboard Sentinel-5P satellite provides methane (CH4) measurements with exceptional temporal and spatial resolution. The study describes a series of improvements developed to retrieve CH4 from TROPOMI. The updated CH4 product features (among others) a more accurate a posteriori correction derived independently of any reference data. The validation of the improved data product shows good agreement with ground-based and satellite measurements, which highlights the quality of the TROPOMI CH4.
Claudia Rivera Cárdenas, Cesar Guarín, Wolfgang Stremme, Martina M. Friedrich, Alejandro Bezanilla, Diana Rivera Ramos, Cristina A. Mendoza-Rodríguez, Michel Grutter, Thomas Blumenstock, and Frank Hase
Atmos. Meas. Tech., 14, 595–613, https://doi.org/10.5194/amt-14-595-2021, https://doi.org/10.5194/amt-14-595-2021, 2021
Jörn Ungermann, Irene Bartolome, Sabine Griessbach, Reinhold Spang, Christian Rolf, Martina Krämer, Michael Höpfner, and Martin Riese
Atmos. Meas. Tech., 13, 7025–7045, https://doi.org/10.5194/amt-13-7025-2020, https://doi.org/10.5194/amt-13-7025-2020, 2020
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This study examines the potential of new IR limb imager instruments and tomographic methods for cloud detection purposes. Simple color-ratio-based methods are examined and compared against more involved nonlinear convex optimization. In a second part, 3-D measurements of the airborne limb sounder GLORIA taken during the Wave-driven ISentropic Exchange campaign are used to exemplarily derive the location and extent of small-scale cirrus clouds with high spatial accuracy.
Robert J. Parker, Alex Webb, Hartmut Boesch, Peter Somkuti, Rocio Barrio Guillo, Antonio Di Noia, Nikoleta Kalaitzi, Jasdeep S. Anand, Peter Bergamaschi, Frederic Chevallier, Paul I. Palmer, Liang Feng, Nicholas M. Deutscher, Dietrich G. Feist, David W. T. Griffith, Frank Hase, Rigel Kivi, Isamu Morino, Justus Notholt, Young-Suk Oh, Hirofumi Ohyama, Christof Petri, David F. Pollard, Coleen Roehl, Mahesh K. Sha, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Yao Té, Voltaire A. Velazco, Thorsten Warneke, Paul O. Wennberg, and Debra Wunch
Earth Syst. Sci. Data, 12, 3383–3412, https://doi.org/10.5194/essd-12-3383-2020, https://doi.org/10.5194/essd-12-3383-2020, 2020
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This work presents the latest release of the University of Leicester GOSAT methane data and acts as the definitive description of this dataset. We detail the processing, validation and evaluation involved in producing these data and highlight its many applications. With now over a decade of global atmospheric methane observations, this dataset has helped, and will continue to help, us better understand the global methane budget and investigate how it may respond to a future changing climate.
Wolfgang Woiwode, Andreas Dörnbrack, Inna Polichtchouk, Sören Johansson, Ben Harvey, Michael Höpfner, Jörn Ungermann, and Felix Friedl-Vallon
Atmos. Chem. Phys., 20, 15379–15387, https://doi.org/10.5194/acp-20-15379-2020, https://doi.org/10.5194/acp-20-15379-2020, 2020
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The lowermost-stratosphere moist bias in ECMWF analyses and 12 h forecasts is diagnosed for the Arctic winter-spring 2016 period by using two-dimensional GLORIA water vapor observations. The bias is already present in the initial conditions (i.e., the analyses), and sensitivity forecasts on time scales of < 12 h show hardly any sensitivity to modified spatial resolution and output frequency.
Sören Johansson, Michael Höpfner, Oliver Kirner, Ingo Wohltmann, Silvia Bucci, Bernard Legras, Felix Friedl-Vallon, Norbert Glatthor, Erik Kretschmer, Jörn Ungermann, and Gerald Wetzel
Atmos. Chem. Phys., 20, 14695–14715, https://doi.org/10.5194/acp-20-14695-2020, https://doi.org/10.5194/acp-20-14695-2020, 2020
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We present high-resolution measurements of pollutant trace gases (PAN, C2H2, and HCOOH) in the Asian monsoon UTLS from the airborne limb imager GLORIA during StratoClim 2017. Enhancements are observed up to 16 km altitude, and PAN and C2H2 even up to 18 km. Two atmospheric models, CAMS and EMAC, reproduce the pollutant's large-scale structures but not finer structures. Convection is investigated using backward trajectories of the models ATLAS and TRACZILLA with advanced detection of convection.
Alessandro Fassò, Michael Sommer, and Christoph von Rohden
Atmos. Meas. Tech., 13, 6445–6458, https://doi.org/10.5194/amt-13-6445-2020, https://doi.org/10.5194/amt-13-6445-2020, 2020
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Modern radiosonde balloons fly from ground level up to the lower stratosphere and take temperature measurements. What is the uncertainty of interpolated values in the resulting atmospheric temperature profiles? To answer this question, we introduce a general statistical–mathematical model for the computation of interpolation uncertainty. Analysing more than 51 million measurements, we provide some understanding of the consequences of filling missing data with interpolated ones.
Erik Lutsch, Kimberly Strong, Dylan B. A. Jones, Thomas Blumenstock, Stephanie Conway, Jenny A. Fisher, James W. Hannigan, Frank Hase, Yasuko Kasai, Emmanuel Mahieu, Maria Makarova, Isamu Morino, Tomoo Nagahama, Justus Notholt, Ivan Ortega, Mathias Palm, Anatoly V. Poberovskii, Ralf Sussmann, and Thorsten Warneke
Atmos. Chem. Phys., 20, 12813–12851, https://doi.org/10.5194/acp-20-12813-2020, https://doi.org/10.5194/acp-20-12813-2020, 2020
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This paper describes the use of a network of 10 Arctic and midlatitude ground-based FTIR measurement sites to detect enhancements of the wildfire tracers carbon monoxide, hydrogen cyanide, and ethane from 2003 to 2018. A tagged CO GEOS-Chem simulation is used for source attribution and to evaluate the relative contribution of CO sources to the FTIR measurements. The use of FTIR measurements allowed for the emission ratios of hydrogen cyanide and ethane to be quantified.
Nicole Jacobs, William R. Simpson, Debra Wunch, Christopher W. O'Dell, Gregory B. Osterman, Frank Hase, Thomas Blumenstock, Qiansi Tu, Matthias Frey, Manvendra K. Dubey, Harrison A. Parker, Rigel Kivi, and Pauli Heikkinen
Atmos. Meas. Tech., 13, 5033–5063, https://doi.org/10.5194/amt-13-5033-2020, https://doi.org/10.5194/amt-13-5033-2020, 2020
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The boreal forest is the largest seasonally varying biospheric CO2-exchange region on Earth. This region is also undergoing amplified climate warming, leading to concerns about the potential for altered regional carbon exchange. Satellite missions, such as the Orbiting Carbon Observatory-2 (OCO-2) project, can measure CO2 abundance over the boreal forest but need validation for the assurance of accuracy. Therefore, we carried out a ground-based validation of OCO-2 CO2 data at three locations.
Mahesh Kumar Sha, Martine De Mazière, Justus Notholt, Thomas Blumenstock, Huilin Chen, Angelika Dehn, David W. T. Griffith, Frank Hase, Pauli Heikkinen, Christian Hermans, Alex Hoffmann, Marko Huebner, Nicholas Jones, Rigel Kivi, Bavo Langerock, Christof Petri, Francis Scolas, Qiansi Tu, and Damien Weidmann
Atmos. Meas. Tech., 13, 4791–4839, https://doi.org/10.5194/amt-13-4791-2020, https://doi.org/10.5194/amt-13-4791-2020, 2020
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We present the results of the 2017 FRM4GHG campaign at the Sodankylä TCCON site aimed at characterising the assessment of several low-cost portable instruments for precise solar absorption measurements of column-averaged dry-air mole fractions of CO2, CH4, and CO. The test instruments provided stable and precise measurements of these gases with quantified small biases. This qualifies the instruments to complement TCCON and expand the global coverage of ground-based measurements of these gases.
Qiansi Tu, Frank Hase, Thomas Blumenstock, Rigel Kivi, Pauli Heikkinen, Mahesh Kumar Sha, Uwe Raffalski, Jochen Landgraf, Alba Lorente, Tobias Borsdorff, Huilin Chen, Florian Dietrich, and Jia Chen
Atmos. Meas. Tech., 13, 4751–4771, https://doi.org/10.5194/amt-13-4751-2020, https://doi.org/10.5194/amt-13-4751-2020, 2020
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Two COCCON instruments are used to observe multiyear greenhouse gases in boreal areas and are compared with the CAMS analysis and S5P satellite data. These three datasets predict greenhouse gas gradients with reasonable agreement. The results indicate that the COCCON instrument has the capability of measuring gradients on regional scales, and observations performed with the portable spectrometers can contribute to inferring sources and sinks and to validating spaceborne greenhouse gases.
Ilya Stanevich, Dylan B. A. Jones, Kimberly Strong, Robert J. Parker, Hartmut Boesch, Debra Wunch, Justus Notholt, Christof Petri, Thorsten Warneke, Ralf Sussmann, Matthias Schneider, Frank Hase, Rigel Kivi, Nicholas M. Deutscher, Voltaire A. Velazco, Kaley A. Walker, and Feng Deng
Geosci. Model Dev., 13, 3839–3862, https://doi.org/10.5194/gmd-13-3839-2020, https://doi.org/10.5194/gmd-13-3839-2020, 2020
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Systematic errors in atmospheric models pose a challenge for inverse modeling studies of methane (CH4) emissions. We evaluated the CH4 simulation in the GEOS-Chem model at the horizontal resolutions of 4° × 5° and 2° × 2.5°. Our analysis identified resolution-dependent biases in the model, which we attributed to discrepancies between the two model resolutions in vertical transport in the troposphere and in stratosphere–troposphere exchange.
Ruud J. Dirksen, Greg E. Bodeker, Peter W. Thorne, Andrea Merlone, Tony Reale, Junhong Wang, Dale F. Hurst, Belay B. Demoz, Tom D. Gardiner, Bruce Ingleby, Michael Sommer, Christoph von Rohden, and Thierry Leblanc
Geosci. Instrum. Method. Data Syst., 9, 337–355, https://doi.org/10.5194/gi-9-337-2020, https://doi.org/10.5194/gi-9-337-2020, 2020
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This paper describes GRUAN's strategy for a network-wide change of the operational radiosonde from Vaisala RS92 to RS41. GRUAN's main goal is to provide long-term data records that are free of inhomogeneities due to instrumental effects, which requires proper change management. The approach is to fully characterize differences between the two radiosonde types using laboratory tests, twin soundings, and ancillary data, as well as by drawing from the various fields of expertise available in GRUAN.
Thomas von Clarmann, Douglas A. Degenstein, Nathaniel J. Livesey, Stefan Bender, Amy Braverman, André Butz, Steven Compernolle, Robert Damadeo, Seth Dueck, Patrick Eriksson, Bernd Funke, Margaret C. Johnson, Yasuko Kasai, Arno Keppens, Anne Kleinert, Natalya A. Kramarova, Alexandra Laeng, Bavo Langerock, Vivienne H. Payne, Alexei Rozanov, Tomohiro O. Sato, Matthias Schneider, Patrick Sheese, Viktoria Sofieva, Gabriele P. Stiller, Christian von Savigny, and Daniel Zawada
Atmos. Meas. Tech., 13, 4393–4436, https://doi.org/10.5194/amt-13-4393-2020, https://doi.org/10.5194/amt-13-4393-2020, 2020
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Remote sensing of atmospheric state variables typically relies on the inverse solution of the radiative transfer equation. An adequately characterized retrieval provides information on the uncertainties of the estimated state variables as well as on how any constraint or a priori assumption affects the estimate. This paper summarizes related techniques and provides recommendations for unified error reporting.
Temesgen Yirdaw Berhe, Gizaw Mengistu Tsidu, Thomas Blumenstock, Frank Hase, and Gabriele P. Stiller
Atmos. Meas. Tech., 13, 4079–4096, https://doi.org/10.5194/amt-13-4079-2020, https://doi.org/10.5194/amt-13-4079-2020, 2020
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The retrieved CH4 and N2O VMR and column amounts from Addis Ababa, tropical site, are found to exhibit very good agreement with all coincident satellite observations (MIPAS, MLS, and AIRS). Furthermore, the bias obtained from the comparison is comparable to the precision of FTIR measurement, which allows the use of data in further scientific studies as it represents a unique environment of tropical Africa, a region poorly investigated in the past.
Benoît Tournadre, Pascale Chelin, Mokhtar Ray, Juan Cuesta, Rebecca D. Kutzner, Xavier Landsheere, Audrey Fortems-Cheiney, Jean-Marie Flaud, Frank Hase, Thomas Blumenstock, Johannes Orphal, Camille Viatte, and Claude Camy-Peyret
Atmos. Meas. Tech., 13, 3923–3937, https://doi.org/10.5194/amt-13-3923-2020, https://doi.org/10.5194/amt-13-3923-2020, 2020
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We present some results about ammonia pollution because NH3, mainly emitted by agricultural activities, is a precursor of fine particles. This study is based on the first multiyear time series (2009–2017) of atmospheric NH3 ground-based measurements over the Paris megacity. This pollutant varies seasonally by 2 orders of magnitude, especially in spring. We highlight that this kind of instrument could be easily installed and is very useful for analyzing NH3 in other megacities or source regions.
Rocco Sedona, Lars Hoffmann, Reinhold Spang, Gabriele Cavallaro, Sabine Griessbach, Michael Höpfner, Matthias Book, and Morris Riedel
Atmos. Meas. Tech., 13, 3661–3682, https://doi.org/10.5194/amt-13-3661-2020, https://doi.org/10.5194/amt-13-3661-2020, 2020
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Polar stratospheric clouds (PSCs) play a key role in polar ozone depletion in the stratosphere. In this paper, we explore the potential of applying machine learning (ML) methods to classify PSC observations of infrared spectra to classify PSC types. ML methods have proved to reach results in line with those obtained using well-established approaches. Among the considered ML methods, random forest (RF) seems to be the most promising one, being able to produce explainable classification results.
Fabio Madonna, Rigel Kivi, Jean-Charles Dupont, Bruce Ingleby, Masatomo Fujiwara, Gonzague Romanens, Miguel Hernandez, Xavier Calbet, Marco Rosoldi, Aldo Giunta, Tomi Karppinen, Masami Iwabuchi, Shunsuke Hoshino, Christoph von Rohden, and Peter William Thorne
Atmos. Meas. Tech., 13, 3621–3649, https://doi.org/10.5194/amt-13-3621-2020, https://doi.org/10.5194/amt-13-3621-2020, 2020
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Radiosondes are one of the primary sources of upper-air data for weather and climate monitoring. In the last two decades, technological progress made available automated radiosonde launchers (ARLs), which are able to replace measurements typically performed manually. This work presents a comparative analysis of the technical performance of the ARLs currently available on the market and contribute to define a strategy to achieve the full traceability of the ARL products.
Christian Borger, Steffen Beirle, Steffen Dörner, Holger Sihler, and Thomas Wagner
Atmos. Meas. Tech., 13, 2751–2783, https://doi.org/10.5194/amt-13-2751-2020, https://doi.org/10.5194/amt-13-2751-2020, 2020
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We present a total column water vapour (TCWV) retrieval analysing measurements from S-5P/TROPOMI in the visible blue spectral range. The retrieval can well capture the global water vapour distribution with similar sensitivity over the land and ocean and agrees well with various reference data sets within the estimated TCWV uncertainties of typically around 10 %–20 %.
Arne Babenhauserheide, Frank Hase, and Isamu Morino
Atmos. Meas. Tech., 13, 2697–2710, https://doi.org/10.5194/amt-13-2697-2020, https://doi.org/10.5194/amt-13-2697-2020, 2020
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This paper demonstrates that the carbon dioxide emissions of Tokyo can be estimated from long-term ground-based measurements of column-averaged atmospheric carbon dioxide abundances recorded at the TCCON site Tsukuba.
Maximilian Reuter, Michael Buchwitz, Oliver Schneising, Stefan Noël, Heinrich Bovensmann, John P. Burrows, Hartmut Boesch, Antonio Di Noia, Jasdeep Anand, Robert J. Parker, Peter Somkuti, Lianghai Wu, Otto P. Hasekamp, Ilse Aben, Akihiko Kuze, Hiroshi Suto, Kei Shiomi, Yukio Yoshida, Isamu Morino, David Crisp, Christopher W. O'Dell, Justus Notholt, Christof Petri, Thorsten Warneke, Voltaire A. Velazco, Nicholas M. Deutscher, David W. T. Griffith, Rigel Kivi, David F. Pollard, Frank Hase, Ralf Sussmann, Yao V. Té, Kimberly Strong, Sébastien Roche, Mahesh K. Sha, Martine De Mazière, Dietrich G. Feist, Laura T. Iraci, Coleen M. Roehl, Christian Retscher, and Dinand Schepers
Atmos. Meas. Tech., 13, 789–819, https://doi.org/10.5194/amt-13-789-2020, https://doi.org/10.5194/amt-13-789-2020, 2020
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We present new satellite-derived data sets of atmospheric carbon dioxide (CO2) and methane (CH4). The data products are column-averaged dry-air mole fractions of CO2 and CH4, denoted XCO2 and XCH4. The products cover the years 2003–2018 and are merged Level 2 (satellite footprints) and merged Level 3 (gridded at monthly time and 5° x 5° spatial resolution) products obtained from combining several individual sensor products. We present the merging algorithms and product validation results.
Jonas Simon Wilzewski, Anke Roiger, Johan Strandgren, Jochen Landgraf, Dietrich G. Feist, Voltaire A. Velazco, Nicholas M. Deutscher, Isamu Morino, Hirofumi Ohyama, Yao Té, Rigel Kivi, Thorsten Warneke, Justus Notholt, Manvendra Dubey, Ralf Sussmann, Markus Rettinger, Frank Hase, Kei Shiomi, and André Butz
Atmos. Meas. Tech., 13, 731–745, https://doi.org/10.5194/amt-13-731-2020, https://doi.org/10.5194/amt-13-731-2020, 2020
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Through spectral degradation of GOSAT measurements in the 1.6 and 2.0 μm spectral bands, we mimic a single-band, passive satellite sensor for monitoring of CO2 emissions at fine spatial scales. We compare retrievals of XCO2 from these bands to TCCON and native GOSAT retrievals. At spectral resolutions near 1.3 nm, XCO2 retrievals from both bands show promising performance, but the 2.0 μm band is favorable due to better noise performance and the potential to retrieve some aerosol information.
Andreas Schneider, Tobias Borsdorff, Joost aan de Brugh, Franziska Aemisegger, Dietrich G. Feist, Rigel Kivi, Frank Hase, Matthias Schneider, and Jochen Landgraf
Atmos. Meas. Tech., 13, 85–100, https://doi.org/10.5194/amt-13-85-2020, https://doi.org/10.5194/amt-13-85-2020, 2020
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This paper presents a new H2O/HDO data set from TROPOMI short-wave infrared measurements. It is validated against recent ground-based FTIR measurements from the TCCON network. A bias in TCCON HDO (which is not verified) is corrected by fitting a correction factor for the HDO column to match MUSICA δD for common observations. The use of the new TROPOMI data set is demonstrated using a case study of a blocking anticyclone over Europe in July 2018.
Oliver Schneising, Michael Buchwitz, Maximilian Reuter, Heinrich Bovensmann, John P. Burrows, Tobias Borsdorff, Nicholas M. Deutscher, Dietrich G. Feist, David W. T. Griffith, Frank Hase, Christian Hermans, Laura T. Iraci, Rigel Kivi, Jochen Landgraf, Isamu Morino, Justus Notholt, Christof Petri, David F. Pollard, Sébastien Roche, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Voltaire A. Velazco, Thorsten Warneke, and Debra Wunch
Atmos. Meas. Tech., 12, 6771–6802, https://doi.org/10.5194/amt-12-6771-2019, https://doi.org/10.5194/amt-12-6771-2019, 2019
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We introduce an algorithm that is used to simultaneously derive the abundances of the important atmospheric constituents carbon monoxide and methane from the TROPOMI instrument onboard the Sentinel-5 Precursor satellite, which enables the determination of both gases with an unprecedented level of detail on a global scale. The quality of the resulting data sets is assessed and the first results are presented.
Minqiang Zhou, Bavo Langerock, Corinne Vigouroux, Mahesh Kumar Sha, Christian Hermans, Jean-Marc Metzger, Huilin Chen, Michel Ramonet, Rigel Kivi, Pauli Heikkinen, Dan Smale, David F. Pollard, Nicholas Jones, Voltaire A. Velazco, Omaira E. García, Matthias Schneider, Mathias Palm, Thorsten Warneke, and Martine De Mazière
Atmos. Meas. Tech., 12, 5979–5995, https://doi.org/10.5194/amt-12-5979-2019, https://doi.org/10.5194/amt-12-5979-2019, 2019
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The differences between the TCCON and NDACC XCO measurements are investigated and discussed based on six NDACC–TCCON sites (Ny-Ålesund, Bremen, Izaña, Saint-Denis, Wollongong and Lauder) using data over the period 2007–2017. The smoothing errors from both TCCON and NDACC measurements are estimated. In addition, the scaling factor of the TCCON XCO data is reassessed by comparing with the AirCore measurements at Sodankylä and Orléans.
Marleen Braun, Jens-Uwe Grooß, Wolfgang Woiwode, Sören Johansson, Michael Höpfner, Felix Friedl-Vallon, Hermann Oelhaf, Peter Preusse, Jörn Ungermann, Björn-Martin Sinnhuber, Helmut Ziereis, and Peter Braesicke
Atmos. Chem. Phys., 19, 13681–13699, https://doi.org/10.5194/acp-19-13681-2019, https://doi.org/10.5194/acp-19-13681-2019, 2019
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We analyse nitrification of the LMS in the Arctic winter 2015–2016 based on GLORIA measurements. Vertical cross sections of HNO3 for several flights show complex fine–scale structures and enhanced values down to 9 km. The extent of overall nitrification is quantified based on HNO3–O3 correlations and reaches between 5 ppbv and 7 ppbv at potential temperature levels between 350 and 380 K. Further, we compare our result with the atmospheric model CLaMS.
Susan S. Kulawik, Sean Crowell, David Baker, Junjie Liu, Kathryn McKain, Colm Sweeney, Sebastien C. Biraud, Steve Wofsy, Christopher W. O'Dell, Paul O. Wennberg, Debra Wunch, Coleen M. Roehl, Nicholas M. Deutscher, Matthäus Kiel, David W. T. Griffith, Voltaire A. Velazco, Justus Notholt, Thorsten Warneke, Christof Petri, Martine De Mazière, Mahesh K. Sha, Ralf Sussmann, Markus Rettinger, Dave F. Pollard, Isamu Morino, Osamu Uchino, Frank Hase, Dietrich G. Feist, Sébastien Roche, Kimberly Strong, Rigel Kivi, Laura Iraci, Kei Shiomi, Manvendra K. Dubey, Eliezer Sepulveda, Omaira Elena Garcia Rodriguez, Yao Té, Pascal Jeseck, Pauli Heikkinen, Edward J. Dlugokencky, Michael R. Gunson, Annmarie Eldering, David Crisp, Brendan Fisher, and Gregory B. Osterman
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2019-257, https://doi.org/10.5194/amt-2019-257, 2019
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This paper provides a benchmark of OCO-2 v8 and ACOS-GOSAT v7.3 XCO2 and lowermost tropospheric (LMT) errors. The paper focuses on the systematic errors and subtracts out validation, co-location, and random errors, looks at the correlation scale-length (spatially and temporally) of systematic errors, finding that the scale lengths are similar to bias correction scale-lengths. The assimilates of the bias correction term is used to place an error on fluxes estimates.
Jacob K. Hedelius, Tai-Long He, Dylan B. A. Jones, Bianca C. Baier, Rebecca R. Buchholz, Martine De Mazière, Nicholas M. Deutscher, Manvendra K. Dubey, Dietrich G. Feist, David W. T. Griffith, Frank Hase, Laura T. Iraci, Pascal Jeseck, Matthäus Kiel, Rigel Kivi, Cheng Liu, Isamu Morino, Justus Notholt, Young-Suk Oh, Hirofumi Ohyama, David F. Pollard, Markus Rettinger, Sébastien Roche, Coleen M. Roehl, Matthias Schneider, Kei Shiomi, Kimberly Strong, Ralf Sussmann, Colm Sweeney, Yao Té, Osamu Uchino, Voltaire A. Velazco, Wei Wang, Thorsten Warneke, Paul O. Wennberg, Helen M. Worden, and Debra Wunch
Atmos. Meas. Tech., 12, 5547–5572, https://doi.org/10.5194/amt-12-5547-2019, https://doi.org/10.5194/amt-12-5547-2019, 2019
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We seek ways to improve the accuracy of column measurements of carbon monoxide (CO) – an important tracer of pollution – made from the MOPITT satellite instrument. We devise a filtering scheme which reduces the scatter and also eliminates bias among the MOPITT detectors. Compared to ground-based observations, MOPITT measurements are about 6 %–8 % higher. When MOPITT data are implemented in a global assimilation model, they tend to reduce the model mismatch with aircraft measurements.
Tobias Borsdorff, Joost aan de Brugh, Andreas Schneider, Alba Lorente, Manfred Birk, Georg Wagner, Rigel Kivi, Frank Hase, Dietrich G. Feist, Ralf Sussmann, Markus Rettinger, Debra Wunch, Thorsten Warneke, and Jochen Landgraf
Atmos. Meas. Tech., 12, 5443–5455, https://doi.org/10.5194/amt-12-5443-2019, https://doi.org/10.5194/amt-12-5443-2019, 2019
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The study presents possible improvements of the TROPOMI CO dataset, which is a primary product of ESA's Sentinel-5P mission. We discuss the use of different molecular spectroscopic databases in the CO retrieval, the induced biases between TROPOMI CO and TCCON validation measurements, and the latitudinally dependent bias between TROPOMI CO and the CAMS-IFS model. Additionally, two methods for the stripe correction of single TROPOMI CO orbits are presented.
Andreas Luther, Ralph Kleinschek, Leon Scheidweiler, Sara Defratyka, Mila Stanisavljevic, Andreas Forstmaier, Alexandru Dandocsi, Sebastian Wolff, Darko Dubravica, Norman Wildmann, Julian Kostinek, Patrick Jöckel, Anna-Leah Nickl, Theresa Klausner, Frank Hase, Matthias Frey, Jia Chen, Florian Dietrich, Jarosław Nȩcki, Justyna Swolkień, Andreas Fix, Anke Roiger, and André Butz
Atmos. Meas. Tech., 12, 5217–5230, https://doi.org/10.5194/amt-12-5217-2019, https://doi.org/10.5194/amt-12-5217-2019, 2019
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Methane ventilated from hard coal mines in the Upper Silesian
Coal Basin in Poland is measured with a mobile Fourier transform spectrometer EM27/SUN. The instrument was mounted on a truck driving in stop-and-go patterns downwind of the methane sources. The emissions are estimated with the cross-sectional flux method. Calculated emissions are in broad agreement with the E-PRTR database. Wind-related errors on the methane estimates dominate the error budget and typically amount to 20 %.
Xinxu Zhao, Julia Marshall, Stephan Hachinger, Christoph Gerbig, Matthias Frey, Frank Hase, and Jia Chen
Atmos. Chem. Phys., 19, 11279–11302, https://doi.org/10.5194/acp-19-11279-2019, https://doi.org/10.5194/acp-19-11279-2019, 2019
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The Weather Research and Forecasting model (WRF), coupled with greenhouse gas (GHG) modules (WRF-GHG), is considered to be a suitable basis for precise GHG transport analysis in urban areas, especially when combined with differential column methodology (DCM). DCM is an effective method not only for comparing models to observations independently of biases caused, for example, by initial conditions, but also for detecting and understanding sources of GHG emissions quantitatively in urban areas.
Dan Weaver, Kimberly Strong, Kaley A. Walker, Chris Sioris, Matthias Schneider, C. Thomas McElroy, Holger Vömel, Michael Sommer, Katja Weigel, Alexei Rozanov, John P. Burrows, William G. Read, Evan Fishbein, and Gabriele Stiller
Atmos. Meas. Tech., 12, 4039–4063, https://doi.org/10.5194/amt-12-4039-2019, https://doi.org/10.5194/amt-12-4039-2019, 2019
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This work assesses water vapour profiles acquired by Atmospheric Chemistry Experiment (ACE) satellite instruments in the upper troposphere and lower stratosphere (UTLS) using comparisons to radiosondes and ground-based Fourier transform infrared spectrometer measurements acquired at a Canadian high Arctic measurement site in Eureka, Nunavut. Additional comparisons are made between these Eureka measurements and other water vapour satellite datasets for context, including AIRS, MLS, and others.
Sören Johansson, Michelle L. Santee, Jens-Uwe Grooß, Michael Höpfner, Marleen Braun, Felix Friedl-Vallon, Farahnaz Khosrawi, Oliver Kirner, Erik Kretschmer, Hermann Oelhaf, Johannes Orphal, Björn-Martin Sinnhuber, Ines Tritscher, Jörn Ungermann, Kaley A. Walker, and Wolfgang Woiwode
Atmos. Chem. Phys., 19, 8311–8338, https://doi.org/10.5194/acp-19-8311-2019, https://doi.org/10.5194/acp-19-8311-2019, 2019
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We present a study based on GLORIA aircraft and MLS/ACE-FTS/CALIOP satellite measurements during the Arctic winter 2015/16, which demonstrate (for the Arctic) unusual chlorine deactivation into HCl instead of ClONO2 due to low ozone abundances in the lowermost stratosphere, with a focus at 380 K potential temperature. The atmospheric models CLaMS and EMAC are evaluated, and measured ClONO2 is linked with transport and in situ deactivation in the lowermost stratosphere.
Temesgen Yirdaw Berhe, Gizaw Mengistu Tsidu, Thomas Blumenstock, Frank Hase, Thomas von Clarmann, Justus Notholt, and Emmanuel Mahieu
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2019-209, https://doi.org/10.5194/amt-2019-209, 2019
Revised manuscript not accepted
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This study aims to assess the latitudinal variation of MIPAS version
V5R_CH4_220 and V5R_CH4_224 uncertainty. Furthermore, we analyze the relationship between these uncertainties and the variability of water vapor. Mainly, the high uncertainty found in tropics for MIPAS CH4 220 is highly associated with variability of water vapour. However, this effect has been reduced in the new updated MIPAS CH4 224 datasets due to jointly fitted water profile with methane.
Debra Wunch, Dylan B. A. Jones, Geoffrey C. Toon, Nicholas M. Deutscher, Frank Hase, Justus Notholt, Ralf Sussmann, Thorsten Warneke, Jeroen Kuenen, Hugo Denier van der Gon, Jenny A. Fisher, and Joannes D. Maasakkers
Atmos. Chem. Phys., 19, 3963–3980, https://doi.org/10.5194/acp-19-3963-2019, https://doi.org/10.5194/acp-19-3963-2019, 2019
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We used five atmospheric observatories in Europe measuring total column dry-air mole fractions of methane and carbon monoxide to infer methane emissions in the area between the observatories. We find that the methane emissions are overestimated by the state-of-the-art inventories, and that this is likely due, at least in part, to the inventory disaggregation. We find that there is significant uncertainty in the carbon monoxide inventories that requires further investigation.
Julian Kostinek, Anke Roiger, Kenneth J. Davis, Colm Sweeney, Joshua P. DiGangi, Yonghoon Choi, Bianca Baier, Frank Hase, Jochen Groß, Maximilian Eckl, Theresa Klausner, and André Butz
Atmos. Meas. Tech., 12, 1767–1783, https://doi.org/10.5194/amt-12-1767-2019, https://doi.org/10.5194/amt-12-1767-2019, 2019
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We demonstrate the successful adaption of a laser-based spectrometer for airborne in situ trace gas measurements. The modified instrument allows for precise and simultaneous airborne observation of five climatologically relevant gases. We further report on instrument performance during a first field deployment over the eastern and central USA.
Felix R. Vogel, Matthias Frey, Johannes Staufer, Frank Hase, Grégoire Broquet, Irène Xueref-Remy, Frédéric Chevallier, Philippe Ciais, Mahesh Kumar Sha, Pascale Chelin, Pascal Jeseck, Christof Janssen, Yao Té, Jochen Groß, Thomas Blumenstock, Qiansi Tu, and Johannes Orphal
Atmos. Chem. Phys., 19, 3271–3285, https://doi.org/10.5194/acp-19-3271-2019, https://doi.org/10.5194/acp-19-3271-2019, 2019
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Providing timely information on greenhouse gas emissions to stakeholders at sub-national scale is an emerging challenge and understanding urban CO2 levels is one key aspect. This study uses atmospheric observations of total column CO2 and compares them to numerical simulations to investigate CO2 levels in the Paris metropolitan area due to natural fluxes and anthropogenic emissions. Our measurements reveal the influence of locally added CO2, which our model is also able to predict.
Matthias Frey, Mahesh K. Sha, Frank Hase, Matthäus Kiel, Thomas Blumenstock, Roland Harig, Gregor Surawicz, Nicholas M. Deutscher, Kei Shiomi, Jonathan E. Franklin, Hartmut Bösch, Jia Chen, Michel Grutter, Hirofumi Ohyama, Youwen Sun, André Butz, Gizaw Mengistu Tsidu, Dragos Ene, Debra Wunch, Zhensong Cao, Omaira Garcia, Michel Ramonet, Felix Vogel, and Johannes Orphal
Atmos. Meas. Tech., 12, 1513–1530, https://doi.org/10.5194/amt-12-1513-2019, https://doi.org/10.5194/amt-12-1513-2019, 2019
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In a 3.5-year long study, the long-term performance of a mobile EM27/SUN spectrometer, used for greenhouse gas observations, is checked with respect to a co-located reference spectrometer. We find that the EM27/SUN is stable on timescales of several years, qualifying it for permanent carbon cycle studies.
The performance of an ensemble of 30 EM27/SUN spectrometers was also tested in the framework of the COllaborative Carbon Column Observing Network (COCCON) and found to be very uniform.
Minqiang Zhou, Bavo Langerock, Kelley C. Wells, Dylan B. Millet, Corinne Vigouroux, Mahesh Kumar Sha, Christian Hermans, Jean-Marc Metzger, Rigel Kivi, Pauli Heikkinen, Dan Smale, David F. Pollard, Nicholas Jones, Nicholas M. Deutscher, Thomas Blumenstock, Matthias Schneider, Mathias Palm, Justus Notholt, James W. Hannigan, and Martine De Mazière
Atmos. Meas. Tech., 12, 1393–1408, https://doi.org/10.5194/amt-12-1393-2019, https://doi.org/10.5194/amt-12-1393-2019, 2019
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N2O is an important atmospheric gas which is observed by two ground-based FTIR networks (TCCON and NDACC). The difference between NDACC and TCCON XN2O measurements is discussed. It is found that the bias between the two networks is within their combined uncertainties. However, TCCON measurements are affected by a priori profiles. In addition, the TCCON and NDACC N2O measurements are compared with the GEOS-Chem model simulations.
Johannes Eckstein, Roland Ruhnke, Stephan Pfahl, Emanuel Christner, Christopher Diekmann, Christoph Dyroff, Daniel Reinert, Daniel Rieger, Matthias Schneider, Jennifer Schröter, Andreas Zahn, and Peter Braesicke
Geosci. Model Dev., 11, 5113–5133, https://doi.org/10.5194/gmd-11-5113-2018, https://doi.org/10.5194/gmd-11-5113-2018, 2018
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We present ICON-ART-Iso, an extension to the global circulation model ICON, which allows for the simulation of the stable isotopologues of water. The main advantage over other isotope-enabled models is its flexible design with respect to the number of tracers simulated. We compare the results of several simulations to measurements of different scale. ICON-ART-Iso is able to reasonably reproduce the measurements. It is a promising tool to aid in the investigation of the atmospheric water cycle.
Christopher W. O'Dell, Annmarie Eldering, Paul O. Wennberg, David Crisp, Michael R. Gunson, Brendan Fisher, Christian Frankenberg, Matthäus Kiel, Hannakaisa Lindqvist, Lukas Mandrake, Aronne Merrelli, Vijay Natraj, Robert R. Nelson, Gregory B. Osterman, Vivienne H. Payne, Thomas E. Taylor, Debra Wunch, Brian J. Drouin, Fabiano Oyafuso, Albert Chang, James McDuffie, Michael Smyth, David F. Baker, Sourish Basu, Frédéric Chevallier, Sean M. R. Crowell, Liang Feng, Paul I. Palmer, Mavendra Dubey, Omaira E. García, David W. T. Griffith, Frank Hase, Laura T. Iraci, Rigel Kivi, Isamu Morino, Justus Notholt, Hirofumi Ohyama, Christof Petri, Coleen M. Roehl, Mahesh K. Sha, Kimberly Strong, Ralf Sussmann, Yao Te, Osamu Uchino, and Voltaire A. Velazco
Atmos. Meas. Tech., 11, 6539–6576, https://doi.org/10.5194/amt-11-6539-2018, https://doi.org/10.5194/amt-11-6539-2018, 2018
Wolfgang Woiwode, Andreas Dörnbrack, Martina Bramberger, Felix Friedl-Vallon, Florian Haenel, Michael Höpfner, Sören Johansson, Erik Kretschmer, Isabell Krisch, Thomas Latzko, Hermann Oelhaf, Johannes Orphal, Peter Preusse, Björn-Martin Sinnhuber, and Jörn Ungermann
Atmos. Chem. Phys., 18, 15643–15667, https://doi.org/10.5194/acp-18-15643-2018, https://doi.org/10.5194/acp-18-15643-2018, 2018
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GLORIA observations during two crossings of the polar front jet stream resolve the fine mesoscale structure of a tropopause fold in high detail. Tracer–tracer correlations of H2O and O3 are presented as a function of potential temperature and reveal an active mixing region. Our study confirms conceptual models of tropopause folds, validates the high quality of ECMWF IFS forecasts, and suggests that mountain waves are capable of modulating exchange processes in the vicinity of tropopause folds.
Michael Höpfner, Terry Deshler, Michael Pitts, Lamont Poole, Reinhold Spang, Gabriele Stiller, and Thomas von Clarmann
Atmos. Meas. Tech., 11, 5901–5923, https://doi.org/10.5194/amt-11-5901-2018, https://doi.org/10.5194/amt-11-5901-2018, 2018
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Polar stratospheric clouds (PSC) have major relevance to the processes leading to polar ozone depletion. A good understanding of these particles is a prerequisite to predict their role in a changing climate. We present the first global set of PSC volume density profiles derived from the MIPAS satellite measurements covering the entire mission period between 2002 and 2012. A comparison to CALIOP lidar measurements is provided. The dataset can serve as a basis for evaluation of atmospheric models.
Tobias Borsdorff, Joost aan de Brugh, Haili Hu, Otto Hasekamp, Ralf Sussmann, Markus Rettinger, Frank Hase, Jochen Gross, Matthias Schneider, Omaira Garcia, Wolfgang Stremme, Michel Grutter, Dietrich G. Feist, Sabrina G. Arnold, Martine De Mazière, Mahesh Kumar Sha, David F. Pollard, Matthäus Kiel, Coleen Roehl, Paul O. Wennberg, Geoffrey C. Toon, and Jochen Landgraf
Atmos. Meas. Tech., 11, 5507–5518, https://doi.org/10.5194/amt-11-5507-2018, https://doi.org/10.5194/amt-11-5507-2018, 2018
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On 13 October 2017, the S5-P satellite was launched with TROPOMI as its only payload. One of the primary products is atmospheric CO observed with daily global coverage and spatial resolution of 7 × 7 km2. The new dataset allows the sensing of CO enhancements above cities and industrial areas and can track pollution transport from biomass burning regions. Through validation with ground-based TCCON measurements we show that the CO data product is already well within the mission requirement.
Corinne Vigouroux, Carlos Augusto Bauer Aquino, Maite Bauwens, Cornelis Becker, Thomas Blumenstock, Martine De Mazière, Omaira García, Michel Grutter, César Guarin, James Hannigan, Frank Hase, Nicholas Jones, Rigel Kivi, Dmitry Koshelev, Bavo Langerock, Erik Lutsch, Maria Makarova, Jean-Marc Metzger, Jean-François Müller, Justus Notholt, Ivan Ortega, Mathias Palm, Clare Paton-Walsh, Anatoly Poberovskii, Markus Rettinger, John Robinson, Dan Smale, Trissevgeni Stavrakou, Wolfgang Stremme, Kim Strong, Ralf Sussmann, Yao Té, and Geoffrey Toon
Atmos. Meas. Tech., 11, 5049–5073, https://doi.org/10.5194/amt-11-5049-2018, https://doi.org/10.5194/amt-11-5049-2018, 2018
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A few ground-based stations have provided time series of HCHO columns until now, which was not optimal for providing good diagnostics for satellite or model validation. In this work, HCHO time series have been determined in a harmonized way at 21 stations ensuring, in addition to a better spatial and level of abundances coverage, that internal biases within the network have been minimized. This data set shows consistent good agreement with model data and is ready for future satellite validation.
Sören Johansson, Wolfgang Woiwode, Michael Höpfner, Felix Friedl-Vallon, Anne Kleinert, Erik Kretschmer, Thomas Latzko, Johannes Orphal, Peter Preusse, Jörn Ungermann, Michelle L. Santee, Tina Jurkat-Witschas, Andreas Marsing, Christiane Voigt, Andreas Giez, Martina Krämer, Christian Rolf, Andreas Zahn, Andreas Engel, Björn-Martin Sinnhuber, and Hermann Oelhaf
Atmos. Meas. Tech., 11, 4737–4756, https://doi.org/10.5194/amt-11-4737-2018, https://doi.org/10.5194/amt-11-4737-2018, 2018
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We present two-dimensional cross sections of temperature, HNO3, O3, ClONO2, H2O and CFC-12 from measurements of the GLORIA infrared limb imager during the POLSTRACC/GW-LCYCLE/SALSA aircraft campaigns in the Arctic winter 2015/2016. GLORIA sounded the atmosphere between 5 and 14 km with vertical resolutions of 0.4–1 km. Estimated errors are in the range of 1–2 K (temperature) and 10 %–20 % (trace gases). Comparisons to in situ instruments onboard the aircraft and to Aura/MLS are shown.
Omaira E. García, Matthias Schneider, Benjamin Ertl, Eliezer Sepúlveda, Christian Borger, Christopher Diekmann, Andreas Wiegele, Frank Hase, Sabine Barthlott, Thomas Blumenstock, Uwe Raffalski, Angel Gómez-Peláez, Martin Steinbacher, Ludwig Ries, and Angel M. de Frutos
Atmos. Meas. Tech., 11, 4171–4215, https://doi.org/10.5194/amt-11-4171-2018, https://doi.org/10.5194/amt-11-4171-2018, 2018
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This work presents the CH4 and N2O products of the MUSICA IASI processor. We analytically assess precisions of 1.5–3 %, good sensitivity in the UTLS region (for CH4 and N2O) and a possibility for retrieving free-tropospheric CH4 at low latitudes independently from CH4 in the UTLS. This is confirmed by comparison to HIPPO profile data (covering a large latitudinal range), continuous GAW data (covering 9 years) and NDACC FTIR data (covering 10 years and three different climate zones).
Farahnaz Khosrawi, Oliver Kirner, Gabriele Stiller, Michael Höpfner, Michelle L. Santee, Sylvia Kellmann, and Peter Braesicke
Atmos. Chem. Phys., 18, 8873–8892, https://doi.org/10.5194/acp-18-8873-2018, https://doi.org/10.5194/acp-18-8873-2018, 2018
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An extensive assessment of the performance of the chemistry–climate model EMAC is given for Arctic winters 2009/2010 and 2010/2011. The EMAC simulations are compared to satellite observations. The comparisons between EMAC simulations and satellite observations show that model and measurements compare well for these two Arctic winters. However, differences between model and observations are found that need improvements in the model in the future.
Rosa Delia García, Africa Barreto, Emilio Cuevas, Julian Gröbner, Omaira Elena García, Angel Gómez-Peláez, Pedro Miguel Romero-Campos, Alberto Redondas, Victoria Eugenia Cachorro, and Ramon Ramos
Geosci. Model Dev., 11, 2139–2152, https://doi.org/10.5194/gmd-11-2139-2018, https://doi.org/10.5194/gmd-11-2139-2018, 2018
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A 7-year comparison study between measured and simulated longwave
downward radiation under cloud-free conditions has been performed at BSRN Izaña. Results show an excellent agreement with a mean bias (simulated–measured) less than 1.1 % and RMSE less than 1 %, which are within the instrumental error (2 %).
Lianghai Wu, Otto Hasekamp, Haili Hu, Jochen Landgraf, Andre Butz, Joost aan de Brugh, Ilse Aben, Dave F. Pollard, David W. T. Griffith, Dietrich G. Feist, Dmitry Koshelev, Frank Hase, Geoffrey C. Toon, Hirofumi Ohyama, Isamu Morino, Justus Notholt, Kei Shiomi, Laura Iraci, Matthias Schneider, Martine de Mazière, Ralf Sussmann, Rigel Kivi, Thorsten Warneke, Tae-Young Goo, and Yao Té
Atmos. Meas. Tech., 11, 3111–3130, https://doi.org/10.5194/amt-11-3111-2018, https://doi.org/10.5194/amt-11-3111-2018, 2018
Youwen Sun, Mathias Palm, Cheng Liu, Frank Hase, David Griffith, Christine Weinzierl, Christof Petri, Wei Wang, and Justus Notholt
Atmos. Meas. Tech., 11, 2879–2896, https://doi.org/10.5194/amt-11-2879-2018, https://doi.org/10.5194/amt-11-2879-2018, 2018
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We simulated instrumental line shape (ILS) degradations with respect to typical types of misalignment, and compared their influence on each NDACC gas. The requirements to suppress the ILS-degradation-related biases within a specified accuracy for all NDACC gases were deduced.
Reinhold Spang, Lars Hoffmann, Rolf Müller, Jens-Uwe Grooß, Ines Tritscher, Michael Höpfner, Michael Pitts, Andrew Orr, and Martin Riese
Atmos. Chem. Phys., 18, 5089–5113, https://doi.org/10.5194/acp-18-5089-2018, https://doi.org/10.5194/acp-18-5089-2018, 2018
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This paper represents an unprecedented pole-covering day- and nighttime climatology of the polar stratospheric clouds (PSCs) based on satellite measurements, their spatial distribution, and composition of different particle types. The climatology has a high potential for the validation and improvement of PSC schemes in chemical transport and chemistry–climate models, which is important for a better prediction of future polar ozone loss in a changing climate.
Annika Günther, Michael Höpfner, Björn-Martin Sinnhuber, Sabine Griessbach, Terry Deshler, Thomas von Clarmann, and Gabriele Stiller
Atmos. Chem. Phys., 18, 1217–1239, https://doi.org/10.5194/acp-18-1217-2018, https://doi.org/10.5194/acp-18-1217-2018, 2018
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Satellite-borne data of sulfur dioxide and a new data set of sulfate aerosol volume densities, as retrieved from MIPAS measurements, are studied in the upper-troposphere–lower-stratosphere region. General patterns of enhanced aerosol are in agreement with SO2. Via chemical transport model simulations for two volcanic eruptions in the Northern Hemisphere midlatitudes, we show that the volcanic enhancements in MIPAS SO2 and sulfate aerosol are consistent in terms of mass and transport patterns.
Xiaoyi Zhao, Dan Weaver, Kristof Bognar, Gloria Manney, Luis Millán, Xin Yang, Edwin Eloranta, Matthias Schneider, and Kimberly Strong
Atmos. Chem. Phys., 17, 14955–14974, https://doi.org/10.5194/acp-17-14955-2017, https://doi.org/10.5194/acp-17-14955-2017, 2017
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Few scientific questions about surface ozone depletion have been addressed, using a variety of measurements and atmospheric models. The lifetime of reactive bromine is only a few hours in the absence of recycling. Evidence of this recycling over aerosol or blowing-snow/ice particles was found at Eureka. The blowing snow sublimation process is a key step in producing bromine-enriched sea-salt aerosol. Ground-based FTIR isotopologue measurements at Eureka provided evidence of this key step.
Gerald Wetzel, Hermann Oelhaf, Michael Höpfner, Felix Friedl-Vallon, Andreas Ebersoldt, Thomas Gulde, Sebastian Kazarski, Oliver Kirner, Anne Kleinert, Guido Maucher, Hans Nordmeyer, Johannes Orphal, Roland Ruhnke, and Björn-Martin Sinnhuber
Atmos. Chem. Phys., 17, 14631–14643, https://doi.org/10.5194/acp-17-14631-2017, https://doi.org/10.5194/acp-17-14631-2017, 2017
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We report the first stratospheric measurements of the diurnal variation in the inorganic bromine (Bry) reservoir species BrONO2 around sunrise and sunset. The main goal of these observations was to check the current understanding of stratospheric bromine chemistry and to estimate the amount of lower-stratospheric Bry. The calculated temporal variation in BrONO2 largely reproduces the balloon-borne observations. The amount of Bry was estimated to be about 21–25 pptv in the lower stratosphere.
Yana A. Virolainen, Yury M. Timofeyev, Vladimir S. Kostsov, Dmitry V. Ionov, Vladislav V. Kalinnikov, Maria V. Makarova, Anatoly V. Poberovsky, Nikita A. Zaitsev, Hamud H. Imhasin, Alexander V. Polyakov, Matthias Schneider, Frank Hase, Sabine Barthlott, and Thomas Blumenstock
Atmos. Meas. Tech., 10, 4521–4536, https://doi.org/10.5194/amt-10-4521-2017, https://doi.org/10.5194/amt-10-4521-2017, 2017
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Water vapour is one of the most important gases in the Earth’s atmosphere and plays a unique role in climate and weather forming. Cross-comparison of different systems for monitoring the atmospheric integrated water vapour (IWV) measurements is an essential part of their testing and validation protocol. We compare coincident measurements of IWV by different techniques over Saint Petersburg (Russia), assess their quality in various atmospheric conditions, and give recommendation for data users.
Margarita Yela, Manuel Gil-Ojeda, Mónica Navarro-Comas, David Gonzalez-Bartolomé, Olga Puentedura, Bernd Funke, Javier Iglesias, Santiago Rodríguez, Omaira García, Héctor Ochoa, and Guillermo Deferrari
Atmos. Chem. Phys., 17, 13373–13389, https://doi.org/10.5194/acp-17-13373-2017, https://doi.org/10.5194/acp-17-13373-2017, 2017
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The paper focuses on stratospheric trends of NO2, a species involved in the ozone equilibrium, using data from four NDACC stations. The global stratospheric NO2 trend has not yet been established conclusively. We analyse DOAS data from stations in the Northern Hemisphere and Southern Hemisphere during 1993–2014. The most relevant finding is the hemispheric asymmetry found in the sign of the NO2 trend, providing further evidence of changes in the stratosphere dynamics on the global scale.
Zhiting Wang, Thorsten Warneke, Nicholas M. Deutscher, Justus Notholt, Ute Karstens, Marielle Saunois, Matthias Schneider, Ralf Sussmann, Harjinder Sembhi, David W. T. Griffith, Dave F. Pollard, Rigel Kivi, Christof Petri, Voltaire A. Velazco, Michel Ramonet, and Huilin Chen
Atmos. Chem. Phys., 17, 13283–13295, https://doi.org/10.5194/acp-17-13283-2017, https://doi.org/10.5194/acp-17-13283-2017, 2017
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In this paper we separate the biases of atmospheric methane models into stratospheric and tropospheric parts. It is observed in other studies that simulated total columns of atmospheric methane present a latitudinal bias compared to measurements. The latitudinal gradients are considered to be from the stratosphere. However, our results show that the latitudinal biases could come from the troposphere in two of three models evaluated in this study.
Farahnaz Khosrawi, Oliver Kirner, Björn-Martin Sinnhuber, Sören Johansson, Michael Höpfner, Michelle L. Santee, Lucien Froidevaux, Jörn Ungermann, Roland Ruhnke, Wolfgang Woiwode, Hermann Oelhaf, and Peter Braesicke
Atmos. Chem. Phys., 17, 12893–12910, https://doi.org/10.5194/acp-17-12893-2017, https://doi.org/10.5194/acp-17-12893-2017, 2017
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The 2015/2016 Arctic winter was one of the coldest winters in recent years, allowing extensive PSC formation and chlorine activation. Model simulations of the 2015/2016 Arctic winter were performed with the atmospheric chemistry–climate model ECHAM5/MESSy Atmospheric Chemistry (EMAC). We find that ozone loss was quite strong but not as strong as in 2010/2011; denitrification and dehydration were so far the strongest observed in the Arctic stratosphere in at least the past 10 years.
Kevin S. Olsen, Kimberly Strong, Kaley A. Walker, Chris D. Boone, Piera Raspollini, Johannes Plieninger, Whitney Bader, Stephanie Conway, Michel Grutter, James W. Hannigan, Frank Hase, Nicholas Jones, Martine de Mazière, Justus Notholt, Matthias Schneider, Dan Smale, Ralf Sussmann, and Naoko Saitoh
Atmos. Meas. Tech., 10, 3697–3718, https://doi.org/10.5194/amt-10-3697-2017, https://doi.org/10.5194/amt-10-3697-2017, 2017
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The primary instrument on the Greenhouse gases Observing SATellite (GOSAT) is the Thermal And Near infrared Sensor for carbon Observations (TANSO) Fourier transform spectrometer (FTS). TANSO-FTS has a thermal infrared channel to retrieve vertical profiles of CO2 and CH4 volume mixing ratios in the troposphere. We compare the retrieved vertical profiles of CH4 from TANSO-FTS with those from two other spaceborne FTSs and with ground-based FTS observatories to assess their quality.
Wolfgang Steinbrecht, Lucien Froidevaux, Ryan Fuller, Ray Wang, John Anderson, Chris Roth, Adam Bourassa, Doug Degenstein, Robert Damadeo, Joe Zawodny, Stacey Frith, Richard McPeters, Pawan Bhartia, Jeannette Wild, Craig Long, Sean Davis, Karen Rosenlof, Viktoria Sofieva, Kaley Walker, Nabiz Rahpoe, Alexei Rozanov, Mark Weber, Alexandra Laeng, Thomas von Clarmann, Gabriele Stiller, Natalya Kramarova, Sophie Godin-Beekmann, Thierry Leblanc, Richard Querel, Daan Swart, Ian Boyd, Klemens Hocke, Niklaus Kämpfer, Eliane Maillard Barras, Lorena Moreira, Gerald Nedoluha, Corinne Vigouroux, Thomas Blumenstock, Matthias Schneider, Omaira García, Nicholas Jones, Emmanuel Mahieu, Dan Smale, Michael Kotkamp, John Robinson, Irina Petropavlovskikh, Neil Harris, Birgit Hassler, Daan Hubert, and Fiona Tummon
Atmos. Chem. Phys., 17, 10675–10690, https://doi.org/10.5194/acp-17-10675-2017, https://doi.org/10.5194/acp-17-10675-2017, 2017
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Thanks to the 1987 Montreal Protocol and its amendments, ozone-depleting chlorine (and bromine) in the stratosphere has declined slowly since the late 1990s. Improved and extended long-term ozone profile observations from satellites and ground-based stations confirm that ozone is responding as expected and has increased by about 2 % per decade since 2000 in the upper stratosphere, around 40 km altitude. At lower altitudes, however, ozone has not changed significantly since 2000.
Dan Weaver, Kimberly Strong, Matthias Schneider, Penny M. Rowe, Chris Sioris, Kaley A. Walker, Zen Mariani, Taneil Uttal, C. Thomas McElroy, Holger Vömel, Alessio Spassiani, and James R. Drummond
Atmos. Meas. Tech., 10, 2851–2880, https://doi.org/10.5194/amt-10-2851-2017, https://doi.org/10.5194/amt-10-2851-2017, 2017
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We have compared techniques used by several PEARL instruments to measure atmospheric water vapour. No single instrument can comprehensively map the atmosphere. We documented how well these techniques perform and quantified the agreement and biases between them. This work showed that new FTIR datasets at PEARL capture accurate measurements of High Arctic water vapour.
Eddy F. Plaza-Medina, Wolfgang Stremme, Alejandro Bezanilla, Michel Grutter, Matthias Schneider, Frank Hase, and Thomas Blumenstock
Atmos. Meas. Tech., 10, 2703–2725, https://doi.org/10.5194/amt-10-2703-2017, https://doi.org/10.5194/amt-10-2703-2017, 2017
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We present data and error estimations of O3 profiles retrieved from spectra measured by a medium- and a high-resolution FTIR spectrometer (located at 2260 m and 3985 m a.s.l.). Above the tropopause both data sets agree well and in accordance with the estimated errors. We introduce a product that combines the two FTIR retrieval results, and a comparison to Mexico City in situ data indicates that the combined product is able to capture the highly varying boundary layer O3 concentrations.
Jorge L. Baylon, Wolfgang Stremme, Michel Grutter, Frank Hase, and Thomas Blumenstock
Atmos. Meas. Tech., 10, 2425–2434, https://doi.org/10.5194/amt-10-2425-2017, https://doi.org/10.5194/amt-10-2425-2017, 2017
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In this investigation we analyze two common optical configurations to retrieve CO2 total column amounts from solar absorption infrared spectra. The noise errors using either a KBr or CaF2 beam splitter, a main component of a Fourier transform infrared spectrometer, are quantified in order to assess the relative precisions of the measurements. A 3-year XCO2 time series at the high-altitude site of Altzomoni in central Mexico presents clear annual and diurnal cycles and a trend of +2.2 ppm yr-1.
Xavier Calbet, Niobe Peinado-Galan, Pilar Rípodas, Tim Trent, Ruud Dirksen, and Michael Sommer
Atmos. Meas. Tech., 10, 2323–2335, https://doi.org/10.5194/amt-10-2323-2017, https://doi.org/10.5194/amt-10-2323-2017, 2017
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GRUAN temperature and water vapour radiosonde measurements are shown to be consistent with infrared hyperspectral measurements from IASI using LBLRTM as a
reference radiative transfer model. Long-term climate data records of temperature and water vapour can be derived from radiosonde measurements and from
space-based instruments. In order to have accurate and homogeneously useful data series, it is a critical necessary condition that these data sets be
consistent with each other.
Petra Hausmann, Ralf Sussmann, Thomas Trickl, and Matthias Schneider
Atmos. Chem. Phys., 17, 7635–7651, https://doi.org/10.5194/acp-17-7635-2017, https://doi.org/10.5194/acp-17-7635-2017, 2017
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We present FTIR soundings (2005–15) of water vapor (H2O) and its isotope ratio (δD) at Zugspitze. Significant {H2O, δD} signatures are found for intercontinental transport events and stratospheric air intrusions to central Europe using backward trajectories and validation by lidar and in situ data. Our results show that {H2O, δD} observations at Zugspitze can serve as indicators for moisture pathways and long-range-transport events, potentially impacting central European climate and air quality.
Debra Wunch, Paul O. Wennberg, Gregory Osterman, Brendan Fisher, Bret Naylor, Coleen M. Roehl, Christopher O'Dell, Lukas Mandrake, Camille Viatte, Matthäus Kiel, David W. T. Griffith, Nicholas M. Deutscher, Voltaire A. Velazco, Justus Notholt, Thorsten Warneke, Christof Petri, Martine De Maziere, Mahesh K. Sha, Ralf Sussmann, Markus Rettinger, David Pollard, John Robinson, Isamu Morino, Osamu Uchino, Frank Hase, Thomas Blumenstock, Dietrich G. Feist, Sabrina G. Arnold, Kimberly Strong, Joseph Mendonca, Rigel Kivi, Pauli Heikkinen, Laura Iraci, James Podolske, Patrick W. Hillyard, Shuji Kawakami, Manvendra K. Dubey, Harrison A. Parker, Eliezer Sepulveda, Omaira E. García, Yao Te, Pascal Jeseck, Michael R. Gunson, David Crisp, and Annmarie Eldering
Atmos. Meas. Tech., 10, 2209–2238, https://doi.org/10.5194/amt-10-2209-2017, https://doi.org/10.5194/amt-10-2209-2017, 2017
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This paper describes the comparisons between NASA's Orbiting Carbon Observatory (OCO-2) column-averaged dry-air mole fractions of CO2 with its primary ground-based validation network, the Total Carbon Column Observing Network (TCCON). The paper shows that while the standard bias correction reduces much of the spurious variability in the satellite measurements, residual biases remain.
Rebecca R. Buchholz, Merritt N. Deeter, Helen M. Worden, John Gille, David P. Edwards, James W. Hannigan, Nicholas B. Jones, Clare Paton-Walsh, David W. T. Griffith, Dan Smale, John Robinson, Kimberly Strong, Stephanie Conway, Ralf Sussmann, Frank Hase, Thomas Blumenstock, Emmanuel Mahieu, and Bavo Langerock
Atmos. Meas. Tech., 10, 1927–1956, https://doi.org/10.5194/amt-10-1927-2017, https://doi.org/10.5194/amt-10-1927-2017, 2017
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The study presents the first systematic use of ground-based remote-sensing data from the Network for the Detection of Atmospheric Composition Change (NDACC) to validate satellite-based Measurements of Pollution in the Troposphere (MOPITT) total column carbon monoxide (CO). MOPITT generally shows low bias with respect to the ground-based instruments. The geographic and temporal dependence of validation results are determined. Our findings inform some recommendations for using MOPITT measurements.
Liang Feng, Paul I. Palmer, Hartmut Bösch, Robert J. Parker, Alex J. Webb, Caio S. C. Correia, Nicholas M. Deutscher, Lucas G. Domingues, Dietrich G. Feist, Luciana V. Gatti, Emanuel Gloor, Frank Hase, Rigel Kivi, Yi Liu, John B. Miller, Isamu Morino, Ralf Sussmann, Kimberly Strong, Osamu Uchino, Jing Wang, and Andreas Zahn
Atmos. Chem. Phys., 17, 4781–4797, https://doi.org/10.5194/acp-17-4781-2017, https://doi.org/10.5194/acp-17-4781-2017, 2017
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We use the GEOS-Chem global 3-D model of atmospheric chemistry and transport and an ensemble Kalman filter to simultaneously infer regional fluxes of methane (CH4) and carbon dioxide (CO2) directly from GOSAT retrievals of XCH4:XCO2, using sparse ground-based CH4 and CO2 mole fraction data to anchor the ratio. Our results show that assimilation of GOSAT data significantly reduced the posterior uncertainty and changed the a priori spatial distribution of CH4 emissions.
Rosa Delia García, Emilio Cuevas, Omaira Elena García, Ramón Ramos, Pedro Miguel Romero-Campos, Fernado de Ory, Victoria Eugenia Cachorro, and Angel de Frutos
Atmos. Meas. Tech., 10, 731–743, https://doi.org/10.5194/amt-10-731-2017, https://doi.org/10.5194/amt-10-731-2017, 2017
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A 1-year intercomparison of classical and modern radiation and sunshine duration instruments has been performed at Izaña Atmospheric Observatory. We compare global solar radiation (GSR) records measured with a Kipp & Zonen CM-21 pyranometer, taken in the framework of the Baseline Surface Radiation Network, with those measured with a multifilter rotating shadowband radiometer and a bimetallic pyranometer, and with GSR estimated from sunshine duration performed with a CS sunshine recorder.
Norbert Glatthor, Michael Höpfner, Adrian Leyser, Gabriele P. Stiller, Thomas von Clarmann, Udo Grabowski, Sylvia Kellmann, Andrea Linden, Björn-Martin Sinnhuber, Gisèle Krysztofiak, and Kaley A. Walker
Atmos. Chem. Phys., 17, 2631–2652, https://doi.org/10.5194/acp-17-2631-2017, https://doi.org/10.5194/acp-17-2631-2017, 2017
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To date, information on the global distribution of atmospheric carbonyl sulfide (OCS) is still rather sparse.
However, detailed knowledge of the OCS distribution is of scientific interest, because this trace gas is on one of the major sources of atmospheric sulfur, which is a prerequisite of the stratospheric aerosol layer. Under this aspect we present a comprehensive space-borne data set of global OCS concentrations covering the period from June 2002 to April 2012.
Whitney Bader, Benoît Bovy, Stephanie Conway, Kimberly Strong, Dan Smale, Alexander J. Turner, Thomas Blumenstock, Chris Boone, Martine Collaud Coen, Ancelin Coulon, Omaira Garcia, David W. T. Griffith, Frank Hase, Petra Hausmann, Nicholas Jones, Paul Krummel, Isao Murata, Isamu Morino, Hideaki Nakajima, Simon O'Doherty, Clare Paton-Walsh, John Robinson, Rodrigue Sandrin, Matthias Schneider, Christian Servais, Ralf Sussmann, and Emmanuel Mahieu
Atmos. Chem. Phys., 17, 2255–2277, https://doi.org/10.5194/acp-17-2255-2017, https://doi.org/10.5194/acp-17-2255-2017, 2017
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An increase of 0.31 ± 0.03 % year−1 of atmospheric methane is reported using 10 years of solar observations performed at 10 ground-based stations since 2005. These trend agree with a GEOS-Chem-tagged simulation that accounts for the contribution of each emission source and one sink in the total methane. The GEOS-Chem simulation shows that anthropogenic emissions from coal mining and gas and oil transport and exploration have played a major role in the increase methane since 2005.
Matthias Schneider, Christian Borger, Andreas Wiegele, Frank Hase, Omaira E. García, Eliezer Sepúlveda, and Martin Werner
Atmos. Meas. Tech., 10, 507–525, https://doi.org/10.5194/amt-10-507-2017, https://doi.org/10.5194/amt-10-507-2017, 2017
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The characteristics of {H2O,δD} pair space-based remote sensing data depend on the atmospheric and surface conditions, which compromises their usage for model evaluation studies. This paper shows how the problem can be overcome by simulating MUSICA MetOp/IASI {H2O,δD} remote sensing products for any given model atmosphere. The remote sensing retrieval simulator is freely provided as a MATLAB and Python routine.
Natalie Kille, Sunil Baidar, Philip Handley, Ivan Ortega, Roman Sinreich, Owen R. Cooper, Frank Hase, James W. Hannigan, Gabriele Pfister, and Rainer Volkamer
Atmos. Meas. Tech., 10, 373–392, https://doi.org/10.5194/amt-10-373-2017, https://doi.org/10.5194/amt-10-373-2017, 2017
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This article describes a new instrument for measuring and quantifying emission fluxes. It introduces the instrument using the solar occultation flux method. Results are presented from the FRAPPE field campaign near Denver, Colorado, from 2014. Calculations of emissions of sources are presented from FRAPPE and compared to emission inventories. Finally, structure functions are calculated to facilitate the future comparison of high-resolution measurements with low resolution satellite measurements.
Emanuel Christner, Martin Kohler, and Matthias Schneider
Atmos. Chem. Phys., 17, 1207–1225, https://doi.org/10.5194/acp-17-1207-2017, https://doi.org/10.5194/acp-17-1207-2017, 2017
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Post-depositional fractionation of stable water isotopes due to fractioning surface evaporation introduces uncertainty to isotope applications such as the reconstruction of paleotemperatures, paleoaltimetry, and the investigation of ground water formation. In this paper we combine measurements of stable water isotopes in near-surface water vapor with a Lagrangian isotope model to investigate isotope fractionation during the evaporation of surface-layer snow in central Europe.
Sabine Barthlott, Matthias Schneider, Frank Hase, Thomas Blumenstock, Matthäus Kiel, Darko Dubravica, Omaira E. García, Eliezer Sepúlveda, Gizaw Mengistu Tsidu, Samuel Takele Kenea, Michel Grutter, Eddy F. Plaza-Medina, Wolfgang Stremme, Kim Strong, Dan Weaver, Mathias Palm, Thorsten Warneke, Justus Notholt, Emmanuel Mahieu, Christian Servais, Nicholas Jones, David W. T. Griffith, Dan Smale, and John Robinson
Earth Syst. Sci. Data, 9, 15–29, https://doi.org/10.5194/essd-9-15-2017, https://doi.org/10.5194/essd-9-15-2017, 2017
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Tropospheric water vapour isotopologue distributions have been consistently generated and quality-filtered for 12 globally distributed ground-based FTIR sites. The products are provided as two data types. The first type is best-suited for tropospheric water vapour distribution studies. The second type is needed for analysing moisture pathways by means of {H2O,δD}-pair distributions. This paper describes the data types and gives recommendations for their correct usage.
Dmitry A. Belikov, Shamil Maksyutov, Alexander Ganshin, Ruslan Zhuravlev, Nicholas M. Deutscher, Debra Wunch, Dietrich G. Feist, Isamu Morino, Robert J. Parker, Kimberly Strong, Yukio Yoshida, Andrey Bril, Sergey Oshchepkov, Hartmut Boesch, Manvendra K. Dubey, David Griffith, Will Hewson, Rigel Kivi, Joseph Mendonca, Justus Notholt, Matthias Schneider, Ralf Sussmann, Voltaire A. Velazco, and Shuji Aoki
Atmos. Chem. Phys., 17, 143–157, https://doi.org/10.5194/acp-17-143-2017, https://doi.org/10.5194/acp-17-143-2017, 2017
André Butz, Anna Solvejg Dinger, Nicole Bobrowski, Julian Kostinek, Lukas Fieber, Constanze Fischerkeller, Giovanni Bruno Giuffrida, Frank Hase, Friedrich Klappenbach, Jonas Kuhn, Peter Lübcke, Lukas Tirpitz, and Qiansi Tu
Atmos. Meas. Tech., 10, 1–14, https://doi.org/10.5194/amt-10-1-2017, https://doi.org/10.5194/amt-10-1-2017, 2017
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Remote sensing of the gaseous composition of non-eruptive, passively degassing volcanic plumes can be a tool for volcano monitoring. Here, we report on a field study that demonstrates the feasibility of remotely measuring the volcanic enhancements of carbon dioxide, hydrogen fluoride, hydrogen chloride, sulfur dioxide, and bromine monoxide in the plume of Mt. Etna using portable spectroscopic instrumentation sampling the plume several kilometers downwind of the source.
Michael Höpfner, Rainer Volkamer, Udo Grabowski, Michel Grutter, Johannes Orphal, Gabriele Stiller, Thomas von Clarmann, and Gerald Wetzel
Atmos. Chem. Phys., 16, 14357–14369, https://doi.org/10.5194/acp-16-14357-2016, https://doi.org/10.5194/acp-16-14357-2016, 2016
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Ammonia (NH3) in the atmosphere is important because of its influence on aerosol and cloud formation and its increasing anthropogenic emissions. We report the first detection of NH3 in the upper troposphere by the analysis of infrared limb emission spectra measured by the MIPAS instrument on Envisat. We have found enhanced values of NH3 within the Asian summer monsoon upper troposphere, where it might contribute to the composition of the Asian tropopause aerosol layer.
Katherine M. Saad, Debra Wunch, Nicholas M. Deutscher, David W. T. Griffith, Frank Hase, Martine De Mazière, Justus Notholt, David F. Pollard, Coleen M. Roehl, Matthias Schneider, Ralf Sussmann, Thorsten Warneke, and Paul O. Wennberg
Atmos. Chem. Phys., 16, 14003–14024, https://doi.org/10.5194/acp-16-14003-2016, https://doi.org/10.5194/acp-16-14003-2016, 2016
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Current approaches to constrain the global methane budget assimilate total column measurements into models, but model biases can impact results. We use tropospheric methane columns to evaluate model transport errors and identify a seasonal time lag in the Northern Hemisphere troposphere masked by stratospheric compensating effects. We find systematic biases in the stratosphere will alias into model-derived emissions estimates, especially those in the high Northern latitudes that vary seasonally.
Andreas Ostler, Ralf Sussmann, Prabir K. Patra, Sander Houweling, Marko De Bruine, Gabriele P. Stiller, Florian J. Haenel, Johannes Plieninger, Philippe Bousquet, Yi Yin, Marielle Saunois, Kaley A. Walker, Nicholas M. Deutscher, David W. T. Griffith, Thomas Blumenstock, Frank Hase, Thorsten Warneke, Zhiting Wang, Rigel Kivi, and John Robinson
Atmos. Meas. Tech., 9, 4843–4859, https://doi.org/10.5194/amt-9-4843-2016, https://doi.org/10.5194/amt-9-4843-2016, 2016
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Our evaluation of column-averaged methane (XCH4) in models and TCCON reveals latitudinal biases between 0.4 % and 2.1 % originating from an inter-model spread in stratospheric CH4. Substituting model stratospheric CH4 fields by satellite data significantly reduces the large XCH4 bias observed for one model. For other models, showing only minor biases, the impact is ambiguous; i.e., the satellite uncertainty range hinders a more accurate model evaluation needed to improve inverse modeling.
Gaétane Ronsmans, Bavo Langerock, Catherine Wespes, James W. Hannigan, Frank Hase, Tobias Kerzenmacher, Emmanuel Mahieu, Matthias Schneider, Dan Smale, Daniel Hurtmans, Martine De Mazière, Cathy Clerbaux, and Pierre-François Coheur
Atmos. Meas. Tech., 9, 4783–4801, https://doi.org/10.5194/amt-9-4783-2016, https://doi.org/10.5194/amt-9-4783-2016, 2016
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HNO3 concentrations are obtained from the IASI instrument and the data set is characterized for the first time in terms of vertical profiles, averaging kernels and error profiles. A validation is also conducted through a comparison with ground-based FTIR measurements, with good results. The data set is then used to analyse HNO3 spatial and temporal variability for the year 2011. The latitudinal gradient and the large seasonal variability in polar regions are well represented with IASI data.
Cristina Robles-Gonzalez, Mónica Navarro-Comas, Olga Puentedura, Matthias Schneider, Frank Hase, Omaira Garcia, Thomas Blumenstock, and Manuel Gil-Ojeda
Atmos. Meas. Tech., 9, 4471–4485, https://doi.org/10.5194/amt-9-4471-2016, https://doi.org/10.5194/amt-9-4471-2016, 2016
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The comparison of observations performed by different techniques and satellite instruments is important. An intercomparison of the stratospheric NO2 derived from ground-based and satellite instruments has been carried out over the Izaña subtropical site. The importance of the use of the effective solar zenith angle when comparing noon measurements with twilight measurements of photochemically active species is highlighted. All instruments show positive trends in NO2 stratospheric column.
Holger Vömel, Tatjana Naebert, Ruud Dirksen, and Michael Sommer
Atmos. Meas. Tech., 9, 3755–3768, https://doi.org/10.5194/amt-9-3755-2016, https://doi.org/10.5194/amt-9-3755-2016, 2016
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This paper describes the fidelity of vertical profile measurements of atmospheric water vapor using the Cryogenic Frostpoint Hygrometer (CFH), which depends on the stability of the calibration, instrument behaviour, and validation of these measurements with respect to a reference. Being able to characterize each of these elements is essential in the understanding long time series of atmospheric water vapor measurements and in the interpretation of water vapor process studies.
Reinhold Spang, Lars Hoffmann, Michael Höpfner, Sabine Griessbach, Rolf Müller, Michael C. Pitts, Andrew M. W. Orr, and Martin Riese
Atmos. Meas. Tech., 9, 3619–3639, https://doi.org/10.5194/amt-9-3619-2016, https://doi.org/10.5194/amt-9-3619-2016, 2016
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We present a new classification approach for different polar stratospheric cloud types. The so-called Bayesian classifier estimates the most likely probability that one of the three PSC types (ice, NAT, or STS) dominates the characteristics of a measured infrared spectrum. The entire measurement period of the satellite instrument MIPAS from July 2002 to April 2013 is processed using the new classifier.
Makoto Inoue, Isamu Morino, Osamu Uchino, Takahiro Nakatsuru, Yukio Yoshida, Tatsuya Yokota, Debra Wunch, Paul O. Wennberg, Coleen M. Roehl, David W. T. Griffith, Voltaire A. Velazco, Nicholas M. Deutscher, Thorsten Warneke, Justus Notholt, John Robinson, Vanessa Sherlock, Frank Hase, Thomas Blumenstock, Markus Rettinger, Ralf Sussmann, Esko Kyrö, Rigel Kivi, Kei Shiomi, Shuji Kawakami, Martine De Mazière, Sabrina G. Arnold, Dietrich G. Feist, Erica A. Barrow, James Barney, Manvendra Dubey, Matthias Schneider, Laura T. Iraci, James R. Podolske, Patrick W. Hillyard, Toshinobu Machida, Yousuke Sawa, Kazuhiro Tsuboi, Hidekazu Matsueda, Colm Sweeney, Pieter P. Tans, Arlyn E. Andrews, Sebastien C. Biraud, Yukio Fukuyama, Jasna V. Pittman, Eric A. Kort, and Tomoaki Tanaka
Atmos. Meas. Tech., 9, 3491–3512, https://doi.org/10.5194/amt-9-3491-2016, https://doi.org/10.5194/amt-9-3491-2016, 2016
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In this study, we correct the biases of GOSAT XCO2 and XCH4 using TCCON data. To evaluate the effectiveness of our correction method, uncorrected/corrected GOSAT data are compared to independent XCO2 and XCH4 data derived from aircraft measurements. Consequently, we suggest that this method is effective for reducing the biases of the GOSAT data. We consider that our work provides GOSAT data users with valuable information and contributes to the further development of studies on greenhouse gases.
Wolfgang Woiwode, Michael Höpfner, Lei Bi, Michael C. Pitts, Lamont R. Poole, Hermann Oelhaf, Sergej Molleker, Stephan Borrmann, Marcus Klingebiel, Gennady Belyaev, Andreas Ebersoldt, Sabine Griessbach, Jens-Uwe Grooß, Thomas Gulde, Martina Krämer, Guido Maucher, Christof Piesch, Christian Rolf, Christian Sartorius, Reinhold Spang, and Johannes Orphal
Atmos. Chem. Phys., 16, 9505–9532, https://doi.org/10.5194/acp-16-9505-2016, https://doi.org/10.5194/acp-16-9505-2016, 2016
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The analysis of spectral signatures of a polar stratospheric cloud in airborne infrared remote sensing observations in the Arctic in combination with further collocated measurements supports the view that the observed cloud consisted of highly aspherical nitric acid trihydrate particles. A characteristic "shoulder-like" spectral signature may be exploited for identification of large, highly aspherical nitric acid trihydrate particles involved in denitrification of the polar winter stratosphere.
E. Eckert, A. Laeng, S. Lossow, S. Kellmann, G. Stiller, T. von Clarmann, N. Glatthor, M. Höpfner, M. Kiefer, H. Oelhaf, J. Orphal, B. Funke, U. Grabowski, F. Haenel, A. Linden, G. Wetzel, W. Woiwode, P. F. Bernath, C. Boone, G. S. Dutton, J. W. Elkins, A. Engel, J. C. Gille, F. Kolonjari, T. Sugita, G. C. Toon, and K. A. Walker
Atmos. Meas. Tech., 9, 3355–3389, https://doi.org/10.5194/amt-9-3355-2016, https://doi.org/10.5194/amt-9-3355-2016, 2016
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We investigate the accuracy, precision and long-term stability of the MIPAS Envisat IMK/IAA CFC-11 (CCl3F) and CFC-12 (CCl2F2) products.
For comparisons we use several data products from satellite, airplane and balloon-borne instruments as well as ground-based data.
MIPAS Envisat CFC-11 has a slight high bias at the lower end of the profile.
CFC-12 agrees well with other data products.
The temporal stability is good up to ~ 30 km, but still leaves room for improvement.
Matthias Schneider, Andreas Wiegele, Sabine Barthlott, Yenny González, Emanuel Christner, Christoph Dyroff, Omaira E. García, Frank Hase, Thomas Blumenstock, Eliezer Sepúlveda, Gizaw Mengistu Tsidu, Samuel Takele Kenea, Sergio Rodríguez, and Javier Andrey
Atmos. Meas. Tech., 9, 2845–2875, https://doi.org/10.5194/amt-9-2845-2016, https://doi.org/10.5194/amt-9-2845-2016, 2016
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Tropospheric {H2O,δD} pairs can be observed by remote sensing techniques, but the data quality strongly depends on a comprehensive consideration of the complex nature and a careful calibration of the remote sensing data pairs. This paper reviews the quality assurance/documentation activities of the MUSICA project and demonstrates that MUSICA’s ground-based FTIR and space-based IASI {H2O,δD} pair products are accurate and can be generated at a global scale with high resolution and for long periods.
Maya García-Comas, Manuel López-Puertas, Bernd Funke, Á. Aythami Jurado-Navarro, Angela Gardini, Gabriele P. Stiller, Thomas von Clarmann, and Michael Höpfner
Atmos. Chem. Phys., 16, 6701–6719, https://doi.org/10.5194/acp-16-6701-2016, https://doi.org/10.5194/acp-16-6701-2016, 2016
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We have analysed IR measurements of PMCs in the NH and SH from 2005 to 2012. This technique is sensitive to the total ice volume independent of particle size. For the first time, we have measured the total ice volume from the midlatitudes to the poles. The data indicate a layer of ice from 81 to 89 km and from the poles to 50–60º in each hemisphere, increasing near the poles. The ice density is larger in the NH than in the SH and located 1 km lower. PMCs also show a diurnal variation.
Dietrich G. Feist, Sabrina G. Arnold, Frank Hase, and Dirk Ponge
Atmos. Meas. Tech., 9, 2381–2391, https://doi.org/10.5194/amt-9-2381-2016, https://doi.org/10.5194/amt-9-2381-2016, 2016
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Optical equipment is usually not made for harsh environments. At our atmospheric observation site on Ascension Island, commercially available optical mirrors were destroyed within weeks after being installed outside. To be able to continue our observations, we had to develop rugged optical mirrors that are able to sustain sea salt spray, volcanic dust, and regular cleaning without loosing their reflectivity and without adverse effects on the retrieval quality.
Omaira Elena García, Eliezer Sepúlveda, Matthias Schneider, Frank Hase, Thomas August, Thomas Blumenstock, Sven Kühl, Rosemary Munro, Ángel Jesús Gómez-Peláez, Tim Hultberg, Alberto Redondas, Sabine Barthlott, Andreas Wiegele, Yenny González, and Esther Sanromá
Atmos. Meas. Tech., 9, 2315–2333, https://doi.org/10.5194/amt-9-2315-2016, https://doi.org/10.5194/amt-9-2315-2016, 2016
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Atmospheric remote sounding from space is fundamental for investigating the processes driving climate change. However, for a correct scientific interpretation of these records a documentation of their quality is required. In this context, this paper exploits the high potential of the Izaña Atmospheric Observatory, as a ground-based reference site, to perform the first comprehensive validation of the EUMETSAT atmospheric trace gas products O3, CH4, N2O, CO and CO2 of the remote sensor IASI.
Frank Hase, Matthias Frey, Matthäus Kiel, Thomas Blumenstock, Roland Harig, Axel Keens, and Johannes Orphal
Atmos. Meas. Tech., 9, 2303–2313, https://doi.org/10.5194/amt-9-2303-2016, https://doi.org/10.5194/amt-9-2303-2016, 2016
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We describe an extension of a portable FTIR (Fourier transform infrafed) spectrometer dedicated to the measurement of column-averaged abundances of greenhouse gases in the atmosphere. The measurement principle is based on a spectrally resolved solar absorption observation (trace gas amounts are deduced from the strength of near-infrared absorption bands). The dual-channel set-up presented here allows co-observing CO while maintaining the highly favourable characteristics of the original device.
Ugo Cortesi, Samuele Del Bianco, Simone Ceccherini, Marco Gai, Bianca Maria Dinelli, Elisa Castelli, Hermann Oelhaf, Wolfgang Woiwode, Michael Höpfner, and Daniel Gerber
Atmos. Meas. Tech., 9, 2267–2289, https://doi.org/10.5194/amt-9-2267-2016, https://doi.org/10.5194/amt-9-2267-2016, 2016
Matthäus Kiel, Frank Hase, Thomas Blumenstock, and Oliver Kirner
Atmos. Meas. Tech., 9, 2223–2239, https://doi.org/10.5194/amt-9-2223-2016, https://doi.org/10.5194/amt-9-2223-2016, 2016
E. Cuevas, Á. J. Gómez-Peláez, S. Rodríguez, E. Terradellas, S. Basart, R. D. García, O. E. García, and S. Alonso-Pérez
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-287, https://doi.org/10.5194/acp-2016-287, 2016
Revised manuscript not accepted
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We revise the North African Dipole Intensity (NAFDI) index, and explain and quantify its relationship with the Saharan Heat Low (SHL) and mid-latitude Rossby waves. An analysis of aerosol optical depth anomalies over Northern Africa is performed for each phase of NAFDI/SHL. A comprehensive top-down conceptual model is introduced to explain the relationships between the NAFDI, the SHL and the mid-latitude Rossby waves and their impact in dust mobilization and transport in Northern Africa.
Yenny González, Matthias Schneider, Christoph Dyroff, Sergio Rodríguez, Emanuel Christner, Omaira Elena García, Emilio Cuevas, Juan Jose Bustos, Ramon Ramos, Carmen Guirado-Fuentes, Sabine Barthlott, Andreas Wiegele, and Eliezer Sepúlveda
Atmos. Chem. Phys., 16, 4251–4269, https://doi.org/10.5194/acp-16-4251-2016, https://doi.org/10.5194/acp-16-4251-2016, 2016
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Measurements of water vapour isotopologues, dust, and a back trajectory model were used to identify moisture pathways in the subtropical North Atlantic. Dry air masses, from condensation at low temperatures, are transported from high altitudes and latitudes. The humid sources are related to the mixture, with lower and more humid air during transport. Rain re-evaporation was an occasional source of moisture. In summer, an important humidity source is the strong dry convection over the Sahara.
Minqiang Zhou, Bart Dils, Pucai Wang, Rob Detmers, Yukio Yoshida, Christopher W. O'Dell, Dietrich G. Feist, Voltaire Almario Velazco, Matthias Schneider, and Martine De Mazière
Atmos. Meas. Tech., 9, 1415–1430, https://doi.org/10.5194/amt-9-1415-2016, https://doi.org/10.5194/amt-9-1415-2016, 2016
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The sun-glint XCO2 and XCH4 products (“ocean data”) of thermal and near infrared sensor for carbon observations Fourier transform spectrometer (TANSO-FTS) on board the Greenhouse Gases Observing Satellite (GOSAT) from several retrieval algorithms is compared with the FTIR measurements form near-ocean Total Carbon Column Observing Network (TCCON) sites, and the results indicate that the ocean data show a good agreement with TCCON measurements.
Susan Kulawik, Debra Wunch, Christopher O'Dell, Christian Frankenberg, Maximilian Reuter, Tomohiro Oda, Frederic Chevallier, Vanessa Sherlock, Michael Buchwitz, Greg Osterman, Charles E. Miller, Paul O. Wennberg, David Griffith, Isamu Morino, Manvendra K. Dubey, Nicholas M. Deutscher, Justus Notholt, Frank Hase, Thorsten Warneke, Ralf Sussmann, John Robinson, Kimberly Strong, Matthias Schneider, Martine De Mazière, Kei Shiomi, Dietrich G. Feist, Laura T. Iraci, and Joyce Wolf
Atmos. Meas. Tech., 9, 683–709, https://doi.org/10.5194/amt-9-683-2016, https://doi.org/10.5194/amt-9-683-2016, 2016
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To accurately estimate source and sink locations of carbon dioxide, systematic errors in satellite measurements and models must be characterized. This paper examines two satellite data sets (GOSAT, launched 2009, and SCIAMACHY, launched 2002), and two models (CarbonTracker and MACC) vs. the TCCON CO2 validation data set. We assess biases and errors by season and latitude, satellite performance under averaging, and diurnal variability. Our findings are useful for assimilation of satellite data.
M. Kiel, D. Wunch, P. O. Wennberg, G. C. Toon, F. Hase, and T. Blumenstock
Atmos. Meas. Tech., 9, 669–682, https://doi.org/10.5194/amt-9-669-2016, https://doi.org/10.5194/amt-9-669-2016, 2016
Sébastien Massart, Anna Agustí-Panareda, Jens Heymann, Michael Buchwitz, Frédéric Chevallier, Maximilian Reuter, Michael Hilker, John P. Burrows, Nicholas M. Deutscher, Dietrich G. Feist, Frank Hase, Ralf Sussmann, Filip Desmet, Manvendra K. Dubey, David W. T. Griffith, Rigel Kivi, Christof Petri, Matthias Schneider, and Voltaire A. Velazco
Atmos. Chem. Phys., 16, 1653–1671, https://doi.org/10.5194/acp-16-1653-2016, https://doi.org/10.5194/acp-16-1653-2016, 2016
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This study presents the European Centre for Medium-Range Weather Forecasts (ECMWF) monitoring of atmospheric CO2 using measurements from the Greenhouse gases Observing Satellite (GOSAT). We show that the modelled CO2 has a better precision than standard CO2 satellite products compared to ground-based measurements. We also present the CO2 forecast based on our best knowledge of the atmospheric CO2 distribution. We show that it has skill to forecast the largest scale CO2 patterns up to day 5.
T. Ning, J. Wang, G. Elgered, G. Dick, J. Wickert, M. Bradke, M. Sommer, R. Querel, and D. Smale
Atmos. Meas. Tech., 9, 79–92, https://doi.org/10.5194/amt-9-79-2016, https://doi.org/10.5194/amt-9-79-2016, 2016
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Integrated water vapour (IWV) obtained from GNSS is to be developed into a GRUAN data product. In addition to the actual measurement, this data product needs to provide an estimate of the measurement uncertainty at the same time resolution as the actual measurement. The method developed in the paper fulfils the requirement by assigning a specific uncertainty to each data point. The method is also valuable for all applications of GNSS IWV data in atmospheric research and weather forecast.
R. D. García, O. E. García, E. Cuevas, V. E. Cachorro, A. Barreto, C. Guirado-Fuentes, N. Kouremeti, J. J. Bustos, P. M. Romero-Campos, and A. M. de Frutos
Atmos. Meas. Tech., 9, 53–62, https://doi.org/10.5194/amt-9-53-2016, https://doi.org/10.5194/amt-9-53-2016, 2016
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This paper presents the reconstruction of a 73-year time series of the aerosol optical depth (AOD) at 500 nm at the subtropical high-mountain Izaña Atmospheric Observatory (IZO) located in Tenerife (Canary Islands, Spain). For this purpose, we have combined AOD estimates from artificial neural networks (ANNs) from 1941 to 2001 and AOD measurements directly obtained with a precision filter radiometer (PFR) between 2003 and 2013.
F. Klappenbach, M. Bertleff, J. Kostinek, F. Hase, T. Blumenstock, A. Agusti-Panareda, M. Razinger, and A. Butz
Atmos. Meas. Tech., 8, 5023–5038, https://doi.org/10.5194/amt-8-5023-2015, https://doi.org/10.5194/amt-8-5023-2015, 2015
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Measurements of atmospheric carbon dioxide and methane total vertical column abundance from onboard the research vessel "RV Polarstern" in March / April 2014. Along the journey on the Atlantic from Cape Town (South Africa) to Bremerhaven (Germany) we could reproduce the interhemispheric gradient of the target gases, and we compared the measurements with satellite and model data. Future campaigns could use the new mobility to characterize sources and sinks of carbon-dioxide and methane.
H. Lindqvist, C. W. O'Dell, S. Basu, H. Boesch, F. Chevallier, N. Deutscher, L. Feng, B. Fisher, F. Hase, M. Inoue, R. Kivi, I. Morino, P. I. Palmer, R. Parker, M. Schneider, R. Sussmann, and Y. Yoshida
Atmos. Chem. Phys., 15, 13023–13040, https://doi.org/10.5194/acp-15-13023-2015, https://doi.org/10.5194/acp-15-13023-2015, 2015
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Atmospheric carbon dioxide concentration varies seasonally mainly due to plant photosynthesis in the Northern Hemisphere. We found that the satellite GOSAT can capture this variability from space to within 1ppm. We also found that models can differ by more than 1ppm. This implies that the satellite measurements could be useful in evaluating models and their prior estimates of carbon dioxide sources and sinks.
R. J. Parker, H. Boesch, K. Byckling, A. J. Webb, P. I. Palmer, L. Feng, P. Bergamaschi, F. Chevallier, J. Notholt, N. Deutscher, T. Warneke, F. Hase, R. Sussmann, S. Kawakami, R. Kivi, D. W. T. Griffith, and V. Velazco
Atmos. Meas. Tech., 8, 4785–4801, https://doi.org/10.5194/amt-8-4785-2015, https://doi.org/10.5194/amt-8-4785-2015, 2015
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Atmospheric CH4 is an important greenhouse gas. Long-term global observations are necessary to understand its behaviour, with satellite observations playing a key role. The "proxy" retrieval method is one of the most successful but relies on the contribution from atmospheric CO2 models. This work assesses the significance of the uncertainty from the model CO2 within the retrieval and determines that despite this uncertainty the data are still valuable for determining sources and sinks of CH4.
J. Plieninger, T. von Clarmann, G. P. Stiller, U. Grabowski, N. Glatthor, S. Kellmann, A. Linden, F. Haenel, M. Kiefer, M. Höpfner, A. Laeng, and S. Lossow
Atmos. Meas. Tech., 8, 4657–4670, https://doi.org/10.5194/amt-8-4657-2015, https://doi.org/10.5194/amt-8-4657-2015, 2015
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We present our revised CH4 and N2O profiles derived from MIPAS-ENVISAT spectra, which are now available for the entire measurement period. We describe the retrieval of the profiles and discuss the improvements compared to earlier versions and their effect on the mixing ratios. We analyse the averaging kernels and the resolution of the profiles. An error discussion for both gases is given.
V. Duflot, C. Wespes, L. Clarisse, D. Hurtmans, Y. Ngadi, N. Jones, C. Paton-Walsh, J. Hadji-Lazaro, C. Vigouroux, M. De Mazière, J.-M. Metzger, E. Mahieu, C. Servais, F. Hase, M. Schneider, C. Clerbaux, and P.-F. Coheur
Atmos. Chem. Phys., 15, 10509–10527, https://doi.org/10.5194/acp-15-10509-2015, https://doi.org/10.5194/acp-15-10509-2015, 2015
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We present global distributions of acetylene (C2H2) and hydrogen cyanide (HCN) total
columns derived from the Infrared Atmospheric Sounding Interferometer (IASI). C2H2 and HCN are ubiquitous atmospheric trace gases with medium tropospheric lifetime, which are frequently used as indicators of combustion sources and as tracers for atmospheric transport and chemistry. We show that there is an overall agreement between ground-based and space measurements, as well as model simulations.
R. Checa-Garcia, J. Landgraf, A. Galli, F. Hase, V. A. Velazco, H. Tran, V. Boudon, F. Alkemade, and A. Butz
Atmos. Meas. Tech., 8, 3617–3629, https://doi.org/10.5194/amt-8-3617-2015, https://doi.org/10.5194/amt-8-3617-2015, 2015
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The future satellite missions Sentinel-5 and its precursor will monitor methane column average dry air mole fractions. The ambitious accuracy required on regional scales demands a characterization of the systematic error sources in which spectroscopic uncertainties are crucial. This study investigates how methane and water vapour spectroscopic errors propagate into retrieval errors, showing that spectroscopy-induced errors exceed 0.6% in large parts of the
world and are regionally correlated.
G. Mengistu Tsidu, T. Blumenstock, and F. Hase
Atmos. Meas. Tech., 8, 3277–3295, https://doi.org/10.5194/amt-8-3277-2015, https://doi.org/10.5194/amt-8-3277-2015, 2015
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Intercomparison of precipitable water vapour from ERA-Interim, Fourier transform infrared spectrometer, GPS and radiosonde over complex topography of Ethiopia was made for the first time over a data-void region of eastern Africa. The study reveals weakness of ERA-Interim reanalysis in capturing diurnal and to some extent seasonal variabilities. The weakness can be improved through additional data assimilation, adaptation of convection and land surface modules to the reality in the region.
T. Guggenmoser, J. Blank, A. Kleinert, T. Latzko, J. Ungermann, F. Friedl-Vallon, M. Höpfner, M. Kaufmann, E. Kretschmer, G. Maucher, T. Neubert, H. Oelhaf, P. Preusse, M. Riese, H. Rongen, M. K. Sha, O. Sumińska-Ebersoldt, and V. Tan
Atmos. Meas. Tech., 8, 3147–3161, https://doi.org/10.5194/amt-8-3147-2015, https://doi.org/10.5194/amt-8-3147-2015, 2015
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The plane-carried Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) measures the thermal radiation emitted by gases and particles in the atmosphere, in a height range of about 5-20 km. In between these measurements, GLORIA is pointed at known radiation sources for calibration. Noise in these calibration measurements can lead to artefacts in the final products. In this paper, we present new techniques which exploit GLORIA's imaging capabilities to reduce these noise effects.
M. Frey, F. Hase, T. Blumenstock, J. Groß, M. Kiel, G. Mengistu Tsidu, K. Schäfer, M. K. Sha, and J. Orphal
Atmos. Meas. Tech., 8, 3047–3057, https://doi.org/10.5194/amt-8-3047-2015, https://doi.org/10.5194/amt-8-3047-2015, 2015
F. Hase, M. Frey, T. Blumenstock, J. Groß, M. Kiel, R. Kohlhepp, G. Mengistu Tsidu, K. Schäfer, M. K. Sha, and J. Orphal
Atmos. Meas. Tech., 8, 3059–3068, https://doi.org/10.5194/amt-8-3059-2015, https://doi.org/10.5194/amt-8-3059-2015, 2015
A. Ostler, R. Sussmann, P. K. Patra, P. O. Wennberg, N. M. Deutscher, D. W. T. Griffith, T. Blumenstock, F. Hase, R. Kivi, T. Warneke, Z. Wang, M. De Mazière, J. Robinson, and H. Ohyama
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-15-20395-2015, https://doi.org/10.5194/acpd-15-20395-2015, 2015
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We find that stratospheric model-transport errors are common for chemical transport models that are used for inverse estimates of CH4 emissions. These model-transport errors cause latitudinal as well as seasonal biases in simulated stratospheric and, hence, column-averaged CH4 mixing ratios (XCH4). Such a model bias corresponds to an overestimation of arctic and mid-latitude CH4 emissions if inversion studies do not apply an ad hoc bias correction before inverting fluxes from XCH4 observations.
J. Heymann, M. Reuter, M. Hilker, M. Buchwitz, O. Schneising, H. Bovensmann, J. P. Burrows, A. Kuze, H. Suto, N. M. Deutscher, M. K. Dubey, D. W. T. Griffith, F. Hase, S. Kawakami, R. Kivi, I. Morino, C. Petri, C. Roehl, M. Schneider, V. Sherlock, R. Sussmann, V. A. Velazco, T. Warneke, and D. Wunch
Atmos. Meas. Tech., 8, 2961–2980, https://doi.org/10.5194/amt-8-2961-2015, https://doi.org/10.5194/amt-8-2961-2015, 2015
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Long-term data sets of global atmospheric carbon dioxide concentrations based on observations from different satellite instruments may suffer from inconsistencies originating from the use of different retrieval algorithms. This issue has been addressed by applying the Bremen Optimal Estimation DOAS retrieval algorithm to SCIAMACHY and TANSO-FTS observations. Detailed comparisons with TCCON and CarbonTracker show good consistency between the SCIAMACHY and TANSO-FTS data sets.
A. J. Turner, D. J. Jacob, K. J. Wecht, J. D. Maasakkers, E. Lundgren, A. E. Andrews, S. C. Biraud, H. Boesch, K. W. Bowman, N. M. Deutscher, M. K. Dubey, D. W. T. Griffith, F. Hase, A. Kuze, J. Notholt, H. Ohyama, R. Parker, V. H. Payne, R. Sussmann, C. Sweeney, V. A. Velazco, T. Warneke, P. O. Wennberg, and D. Wunch
Atmos. Chem. Phys., 15, 7049–7069, https://doi.org/10.5194/acp-15-7049-2015, https://doi.org/10.5194/acp-15-7049-2015, 2015
M. Höpfner, C. D. Boone, B. Funke, N. Glatthor, U. Grabowski, A. Günther, S. Kellmann, M. Kiefer, A. Linden, S. Lossow, H. C. Pumphrey, W. G. Read, A. Roiger, G. Stiller, H. Schlager, T. von Clarmann, and K. Wissmüller
Atmos. Chem. Phys., 15, 7017–7037, https://doi.org/10.5194/acp-15-7017-2015, https://doi.org/10.5194/acp-15-7017-2015, 2015
W. Woiwode, O. Sumińska-Ebersoldt, H. Oelhaf, M. Höpfner, G. V. Belyaev, A. Ebersoldt, F. Friedl-Vallon, J.-U. Grooß, T. Gulde, M. Kaufmann, A. Kleinert, M. Krämer, E. Kretschmer, T. Kulessa, G. Maucher, T. Neubert, C. Piesch, P. Preusse, M. Riese, H. Rongen, C. Sartorius, G. Schardt, A. Schönfeld, D. Schuettemeyer, M. K. Sha, F. Stroh, J. Ungermann, C. M. Volk, and J. Orphal
Atmos. Meas. Tech., 8, 2509–2520, https://doi.org/10.5194/amt-8-2509-2015, https://doi.org/10.5194/amt-8-2509-2015, 2015
J. Ungermann, J. Blank, M. Dick, A. Ebersoldt, F. Friedl-Vallon, A. Giez, T. Guggenmoser, M. Höpfner, T. Jurkat, M. Kaufmann, S. Kaufmann, A. Kleinert, M. Krämer, T. Latzko, H. Oelhaf, F. Olchewski, P. Preusse, C. Rolf, J. Schillings, O. Suminska-Ebersoldt, V. Tan, N. Thomas, C. Voigt, A. Zahn, M. Zöger, and M. Riese
Atmos. Meas. Tech., 8, 2473–2489, https://doi.org/10.5194/amt-8-2473-2015, https://doi.org/10.5194/amt-8-2473-2015, 2015
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The GLORIA sounder is an airborne infrared limb-imager combining a two-dimensional infrared detector with a Fourier transform spectrometer. It was operated aboard the new German Gulfstream G550 research aircraft HALO during the TACTS and ESMVAL campaigns in summer 2012. This paper describes the retrieval of temperature, as well as H2O, HNO3, and O3 cross sections from GLORIA dynamics mode spectra. A high correlation is achieved between the remote sensing and the in situ trace gas measurements.
C. Dyroff, S. Sanati, E. Christner, A. Zahn, M. Balzer, H. Bouquet, J. B. McManus, Y. González-Ramos, and M. Schneider
Atmos. Meas. Tech., 8, 2037–2049, https://doi.org/10.5194/amt-8-2037-2015, https://doi.org/10.5194/amt-8-2037-2015, 2015
R. A. Scheepmaker, C. Frankenberg, N. M. Deutscher, M. Schneider, S. Barthlott, T. Blumenstock, O. E. Garcia, F. Hase, N. Jones, E. Mahieu, J. Notholt, V. Velazco, J. Landgraf, and I. Aben
Atmos. Meas. Tech., 8, 1799–1818, https://doi.org/10.5194/amt-8-1799-2015, https://doi.org/10.5194/amt-8-1799-2015, 2015
C. Piesch, C. Sartorius, F. Friedl-Vallon, T. Gulde, S. Heger, E. Kretschmer, G. Maucher, H. Nordmeyer, J. Barthel, A. Ebersoldt, F. Graf, F. Hase, A. Kleinert, T. Neubert, and H. J. Schillings
Atmos. Meas. Tech., 8, 1773–1787, https://doi.org/10.5194/amt-8-1773-2015, https://doi.org/10.5194/amt-8-1773-2015, 2015
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The paper shows the design and the technics of the GLORIA spectrometer, the dedicated cooling system, and the performance during operation on HALO aircraft.
S. Barthlott, M. Schneider, F. Hase, A. Wiegele, E. Christner, Y. González, T. Blumenstock, S. Dohe, O. E. García, E. Sepúlveda, K. Strong, J. Mendonca, D. Weaver, M. Palm, N. M. Deutscher, T. Warneke, J. Notholt, B. Lejeune, E. Mahieu, N. Jones, D. W. T. Griffith, V. A. Velazco, D. Smale, J. Robinson, R. Kivi, P. Heikkinen, and U. Raffalski
Atmos. Meas. Tech., 8, 1555–1573, https://doi.org/10.5194/amt-8-1555-2015, https://doi.org/10.5194/amt-8-1555-2015, 2015
J.-L. Lacour, L. Clarisse, J. Worden, M. Schneider, S. Barthlott, F. Hase, C. Risi, C. Clerbaux, D. Hurtmans, and P.-F. Coheur
Atmos. Meas. Tech., 8, 1447–1466, https://doi.org/10.5194/amt-8-1447-2015, https://doi.org/10.5194/amt-8-1447-2015, 2015
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This paper describes a cross-validation study of tropospheric δD (HDO/H2O ratio) profiles retrieved from IASI spectra (retrieval performed at ULB). We document how these profiles compare to profiles derived from TES/AURA sounder and from three ground-based FTIRs of the NDACC network (produced within the MUSICA project). We show that empirical differences are in agreement with the theoretical expected differences which are dominated by IASI observational and the smoothing error components.
C. Vigouroux, T. Blumenstock, M. Coffey, Q. Errera, O. García, N. B. Jones, J. W. Hannigan, F. Hase, B. Liley, E. Mahieu, J. Mellqvist, J. Notholt, M. Palm, G. Persson, M. Schneider, C. Servais, D. Smale, L. Thölix, and M. De Mazière
Atmos. Chem. Phys., 15, 2915–2933, https://doi.org/10.5194/acp-15-2915-2015, https://doi.org/10.5194/acp-15-2915-2015, 2015
M. Schneider, Y. González, C. Dyroff, E. Christner, A. Wiegele, S. Barthlott, O. E. García, E. Sepúlveda, F. Hase, J. Andrey, T. Blumenstock, C. Guirado, R. Ramos, and S. Rodríguez
Atmos. Meas. Tech., 8, 483–503, https://doi.org/10.5194/amt-8-483-2015, https://doi.org/10.5194/amt-8-483-2015, 2015
N. Glatthor, M. Höpfner, G. P. Stiller, T. von Clarmann, B. Funke, S. Lossow, E. Eckert, U. Grabowski, S. Kellmann, A. Linden, K. A. Walker, and A. Wiegele
Atmos. Chem. Phys., 15, 563–582, https://doi.org/10.5194/acp-15-563-2015, https://doi.org/10.5194/acp-15-563-2015, 2015
M. Kaufmann, J. Blank, T. Guggenmoser, J. Ungermann, A. Engel, M. Ern, F. Friedl-Vallon, D. Gerber, J. U. Grooß, G. Guenther, M. Höpfner, A. Kleinert, E. Kretschmer, Th. Latzko, G. Maucher, T. Neubert, H. Nordmeyer, H. Oelhaf, F. Olschewski, J. Orphal, P. Preusse, H. Schlager, H. Schneider, D. Schuettemeyer, F. Stroh, O. Suminska-Ebersoldt, B. Vogel, C. M. Volk, W. Woiwode, and M. Riese
Atmos. Meas. Tech., 8, 81–95, https://doi.org/10.5194/amt-8-81-2015, https://doi.org/10.5194/amt-8-81-2015, 2015
M. Reuter, M. Buchwitz, M. Hilker, J. Heymann, O. Schneising, D. Pillai, H. Bovensmann, J. P. Burrows, H. Bösch, R. Parker, A. Butz, O. Hasekamp, C. W. O'Dell, Y. Yoshida, C. Gerbig, T. Nehrkorn, N. M. Deutscher, T. Warneke, J. Notholt, F. Hase, R. Kivi, R. Sussmann, T. Machida, H. Matsueda, and Y. Sawa
Atmos. Chem. Phys., 14, 13739–13753, https://doi.org/10.5194/acp-14-13739-2014, https://doi.org/10.5194/acp-14-13739-2014, 2014
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Current knowledge about the European terrestrial biospheric carbon sink relies upon bottom-up and global surface flux inverse model estimates using in situ measurements. Our analysis of five satellite data sets comprises a regional inversion designed to be insensitive to potential retrieval biases and transport errors. We show that the satellite-derived sink is larger (1.0±0.3GtC/a) than previous estimates (0.4±0.4GtC/a).
R. J. Dirksen, M. Sommer, F. J. Immler, D. F. Hurst, R. Kivi, and H. Vömel
Atmos. Meas. Tech., 7, 4463–4490, https://doi.org/10.5194/amt-7-4463-2014, https://doi.org/10.5194/amt-7-4463-2014, 2014
A. Kleinert, F. Friedl-Vallon, T. Guggenmoser, M. Höpfner, T. Neubert, R. Ribalda, M. K. Sha, J. Ungermann, J. Blank, A. Ebersoldt, E. Kretschmer, T. Latzko, H. Oelhaf, F. Olschewski, and P. Preusse
Atmos. Meas. Tech., 7, 4167–4184, https://doi.org/10.5194/amt-7-4167-2014, https://doi.org/10.5194/amt-7-4167-2014, 2014
A. Ostler, R. Sussmann, M. Rettinger, N. M. Deutscher, S. Dohe, F. Hase, N. Jones, M. Palm, and B.-M. Sinnhuber
Atmos. Meas. Tech., 7, 4081–4101, https://doi.org/10.5194/amt-7-4081-2014, https://doi.org/10.5194/amt-7-4081-2014, 2014
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Ground-based FTIR soundings of column-average methane from NDACC and TCCON can be combined without the need to apply an overall calibration factor. NDACC and TCCON measurements complement one another and provide valuable information for satellite validation, evaluation of chemical-transport models, and source-sink inversions. The impact of dynamical variability on NDACC and TCCON retrievals of column-average methane is reflected in different smoothing effects.
H. Diémoz, A. M. Siani, A. Redondas, V. Savastiouk, C. T. McElroy, M. Navarro-Comas, and F. Hase
Atmos. Meas. Tech., 7, 4009–4022, https://doi.org/10.5194/amt-7-4009-2014, https://doi.org/10.5194/amt-7-4009-2014, 2014
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- A new algorithm to retrieve nitrogen dioxide by Brewer spectrophotometers was developed.
- Direct sun and zenith sky data recorded at the Izaña observatory were processed with the new algorithm and compared to co-located reference instruments.
- The measurement uncertainty was thoroughly determined by using a Monte Carlo technique.
- The new algorithm can be applied to more than 60 Brewers around the world.
A. Laeng, U. Grabowski, T. von Clarmann, G. Stiller, N. Glatthor, M. Höpfner, S. Kellmann, M. Kiefer, A. Linden, S. Lossow, V. Sofieva, I. Petropavlovskikh, D. Hubert, T. Bathgate, P. Bernath, C. D. Boone, C. Clerbaux, P. Coheur, R. Damadeo, D. Degenstein, S. Frith, L. Froidevaux, J. Gille, K. Hoppel, M. McHugh, Y. Kasai, J. Lumpe, N. Rahpoe, G. Toon, T. Sano, M. Suzuki, J. Tamminen, J. Urban, K. Walker, M. Weber, and J. Zawodny
Atmos. Meas. Tech., 7, 3971–3987, https://doi.org/10.5194/amt-7-3971-2014, https://doi.org/10.5194/amt-7-3971-2014, 2014
F. Friedl-Vallon, T. Gulde, F. Hase, A. Kleinert, T. Kulessa, G. Maucher, T. Neubert, F. Olschewski, C. Piesch, P. Preusse, H. Rongen, C. Sartorius, H. Schneider, A. Schönfeld, V. Tan, N. Bayer, J. Blank, R. Dapp, A. Ebersoldt, H. Fischer, F. Graf, T. Guggenmoser, M. Höpfner, M. Kaufmann, E. Kretschmer, T. Latzko, H. Nordmeyer, H. Oelhaf, J. Orphal, M. Riese, G. Schardt, J. Schillings, M. K. Sha, O. Suminska-Ebersoldt, and J. Ungermann
Atmos. Meas. Tech., 7, 3565–3577, https://doi.org/10.5194/amt-7-3565-2014, https://doi.org/10.5194/amt-7-3565-2014, 2014
R. D. García, E. Cuevas, O. E. García, V. E. Cachorro, P. Pallé, J. J. Bustos, P. M. Romero-Campos, and A. M. de Frutos
Atmos. Meas. Tech., 7, 3139–3150, https://doi.org/10.5194/amt-7-3139-2014, https://doi.org/10.5194/amt-7-3139-2014, 2014
O. E. García, M. Schneider, F. Hase, T. Blumenstock, E. Sepúlveda, and Y. González
Atmos. Meas. Tech., 7, 3071–3084, https://doi.org/10.5194/amt-7-3071-2014, https://doi.org/10.5194/amt-7-3071-2014, 2014
K. M. Saad, D. Wunch, G. C. Toon, P. Bernath, C. Boone, B. Connor, N. M. Deutscher, D. W. T. Griffith, R. Kivi, J. Notholt, C. Roehl, M. Schneider, V. Sherlock, and P. O. Wennberg
Atmos. Meas. Tech., 7, 2907–2918, https://doi.org/10.5194/amt-7-2907-2014, https://doi.org/10.5194/amt-7-2907-2014, 2014
A. Wiegele, M. Schneider, F. Hase, S. Barthlott, O. E. García, E. Sepúlveda, Y. González, T. Blumenstock, U. Raffalski, M. Gisi, and R. Kohlhepp
Atmos. Meas. Tech., 7, 2719–2732, https://doi.org/10.5194/amt-7-2719-2014, https://doi.org/10.5194/amt-7-2719-2014, 2014
N. V. Rokotyan, V. I. Zakharov, K. G. Gribanov, M. Schneider, F.-M. Bréon, J. Jouzel, R. Imasu, M. Werner, M. Butzin, C. Petri, T. Warneke, and J. Notholt
Atmos. Meas. Tech., 7, 2567–2580, https://doi.org/10.5194/amt-7-2567-2014, https://doi.org/10.5194/amt-7-2567-2014, 2014
E. Sepúlveda, M. Schneider, F. Hase, S. Barthlott, D. Dubravica, O. E. García, A. Gomez-Pelaez, Y. González, J. C. Guerra, M. Gisi, R. Kohlhepp, S. Dohe, T. Blumenstock, K. Strong, D. Weaver, M. Palm, A. Sadeghi, N. M. Deutscher, T. Warneke, J. Notholt, N. Jones, D. W. T. Griffith, D. Smale, G. W. Brailsford, J. Robinson, F. Meinhardt, M. Steinbacher, T. Aalto, and D. Worthy
Atmos. Meas. Tech., 7, 2337–2360, https://doi.org/10.5194/amt-7-2337-2014, https://doi.org/10.5194/amt-7-2337-2014, 2014
E. Hache, J.-L. Attié, C. Tourneur, P. Ricaud, L. Coret, W. A. Lahoz, L. El Amraoui, B. Josse, P. Hamer, J. Warner, X. Liu, K. Chance, M. Höpfner, R. Spurr, V. Natraj, S. Kulawik, A. Eldering, and J. Orphal
Atmos. Meas. Tech., 7, 2185–2201, https://doi.org/10.5194/amt-7-2185-2014, https://doi.org/10.5194/amt-7-2185-2014, 2014
M. Riese, H. Oelhaf, P. Preusse, J. Blank, M. Ern, F. Friedl-Vallon, H. Fischer, T. Guggenmoser, M. Höpfner, P. Hoor, M. Kaufmann, J. Orphal, F. Plöger, R. Spang, O. Suminska-Ebersoldt, J. Ungermann, B. Vogel, and W. Woiwode
Atmos. Meas. Tech., 7, 1915–1928, https://doi.org/10.5194/amt-7-1915-2014, https://doi.org/10.5194/amt-7-1915-2014, 2014
B. Dils, M. Buchwitz, M. Reuter, O. Schneising, H. Boesch, R. Parker, S. Guerlet, I. Aben, T. Blumenstock, J. P. Burrows, A. Butz, N. M. Deutscher, C. Frankenberg, F. Hase, O. P. Hasekamp, J. Heymann, M. De Mazière, J. Notholt, R. Sussmann, T. Warneke, D. Griffith, V. Sherlock, and D. Wunch
Atmos. Meas. Tech., 7, 1723–1744, https://doi.org/10.5194/amt-7-1723-2014, https://doi.org/10.5194/amt-7-1723-2014, 2014
F. Deng, D. B. A. Jones, D. K. Henze, N. Bousserez, K. W. Bowman, J. B. Fisher, R. Nassar, C. O'Dell, D. Wunch, P. O. Wennberg, E. A. Kort, S. C. Wofsy, T. Blumenstock, N. M. Deutscher, D. W. T. Griffith, F. Hase, P. Heikkinen, V. Sherlock, K. Strong, R. Sussmann, and T. Warneke
Atmos. Chem. Phys., 14, 3703–3727, https://doi.org/10.5194/acp-14-3703-2014, https://doi.org/10.5194/acp-14-3703-2014, 2014
F. Hase, B. J. Drouin, C. M. Roehl, G. C. Toon, P. O. Wennberg, D. Wunch, T. Blumenstock, F. Desmet, D. G. Feist, P. Heikkinen, M. De Mazière, M. Rettinger, J. Robinson, M. Schneider, V. Sherlock, R. Sussmann, Y. Té, T. Warneke, and C. Weinzierl
Atmos. Meas. Tech., 6, 3527–3537, https://doi.org/10.5194/amt-6-3527-2013, https://doi.org/10.5194/amt-6-3527-2013, 2013
M. Höpfner, N. Glatthor, U. Grabowski, S. Kellmann, M. Kiefer, A. Linden, J. Orphal, G. Stiller, T. von Clarmann, B. Funke, and C. D. Boone
Atmos. Chem. Phys., 13, 10405–10423, https://doi.org/10.5194/acp-13-10405-2013, https://doi.org/10.5194/acp-13-10405-2013, 2013
J. Cuesta, M. Eremenko, X. Liu, G. Dufour, Z. Cai, M. Höpfner, T. von Clarmann, P. Sellitto, G. Foret, B. Gaubert, M. Beekmann, J. Orphal, K. Chance, R. Spurr, and J.-M. Flaud
Atmos. Chem. Phys., 13, 9675–9693, https://doi.org/10.5194/acp-13-9675-2013, https://doi.org/10.5194/acp-13-9675-2013, 2013
S. Dohe, V. Sherlock, F. Hase, M. Gisi, J. Robinson, E. Sepúlveda, M. Schneider, and T. Blumenstock
Atmos. Meas. Tech., 6, 1981–1992, https://doi.org/10.5194/amt-6-1981-2013, https://doi.org/10.5194/amt-6-1981-2013, 2013
C. Brühl, J. Lelieveld, M. Höpfner, and H. Tost
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-11395-2013, https://doi.org/10.5194/acpd-13-11395-2013, 2013
Revised manuscript not accepted
S. Takele Kenea, G. Mengistu Tsidu, T. Blumenstock, F. Hase, T. von Clarmann, and G. P. Stiller
Atmos. Meas. Tech., 6, 495–509, https://doi.org/10.5194/amt-6-495-2013, https://doi.org/10.5194/amt-6-495-2013, 2013
S. Kellmann, T. von Clarmann, G. P. Stiller, E. Eckert, N. Glatthor, M. Höpfner, M. Kiefer, J. Orphal, B. Funke, U. Grabowski, A. Linden, G. S. Dutton, and J. W. Elkins
Atmos. Chem. Phys., 12, 11857–11875, https://doi.org/10.5194/acp-12-11857-2012, https://doi.org/10.5194/acp-12-11857-2012, 2012
M. Schneider, S. Barthlott, F. Hase, Y. González, K. Yoshimura, O. E. García, E. Sepúlveda, A. Gomez-Pelaez, M. Gisi, R. Kohlhepp, S. Dohe, T. Blumenstock, A. Wiegele, E. Christner, K. Strong, D. Weaver, M. Palm, N. M. Deutscher, T. Warneke, J. Notholt, B. Lejeune, P. Demoulin, N. Jones, D. W. T. Griffith, D. Smale, and J. Robinson
Atmos. Meas. Tech., 5, 3007–3027, https://doi.org/10.5194/amt-5-3007-2012, https://doi.org/10.5194/amt-5-3007-2012, 2012
Related subject area
Subject: Gases | Technique: Remote Sensing | Topic: Validation and Intercomparisons
Satellite measurements of peroxyacetyl nitrate from the Cross-Track Infrared Sounder: comparison with ATom aircraft measurements
The SPARC Water Vapor Assessment II: assessment of satellite measurements of upper tropospheric humidity
Ground-based validation of the MetOp-A and MetOp-B GOME-2 OClO measurements
Satellite data validation: a parametrization of the natural variability of atmospheric mixing ratios
Investigation of spaceborne trace gas products over St Petersburg and Yekaterinburg, Russia, by using COllaborative Column Carbon Observing Network (COCCON) observations
On the influence of underlying elevation data on Sentinel-5 Precursor satellite methane retrievals over Greenland
A comparison of the impact of TROPOMI and OMI tropospheric NO2 on global chemical data assimilation
Impact of 3D cloud structures on the atmospheric trace gas products from UV–Vis sounders – Part 1: Synthetic dataset for validation of trace gas retrieval algorithms
Variations of Arctic winter ozone from the LIMS Level 3 dataset
Retrieval of tropospheric aerosol, NO2, and HCHO vertical profiles from MAX-DOAS observations over Thessaloniki, Greece: intercomparison and validation of two inversion algorithms
Assessment of the quality of ACE-FTS stratospheric ozone data
Validation and error estimation of AIRS MUSES CO profiles with HIPPO, ATom, and NOAA GML aircraft observations
Dealing with spatial heterogeneity in pointwise-to-gridded- data comparisons
Biomass burning nitrogen dioxide emissions derived from space with TROPOMI: methodology and validation
Intercomparison of CO measurements from TROPOMI, ACE-FTS, and a high-Arctic ground-based Fourier transform spectrometer
Assessing the feasibility of using a neural network to filter Orbiting Carbon Observatory 2 (OCO-2) retrievals at northern high latitudes
TROPOMI tropospheric ozone column data: geophysical assessment and comparison to ozonesondes, GOME-2B and OMI
Validation of methane and carbon monoxide from Sentinel-5 Precursor using TCCON and NDACC-IRWG stations
Evaluation of the coupled high-resolution atmospheric chemistry model system MECO(n) using in situ and MAX-DOAS NO2 measurements
Total ozone column intercomparison of Brewers, Dobsons, and BTS-Solar at Hohenpeißenberg and Davos in 2019/2020
A systematic assessment of water vapor products in the Arctic: from instantaneous measurements to monthly means
Quality assessment of Dobson spectrophotometers for ozone column measurements before and after automation at Arosa and Davos
Systematic comparison of vectorial spherical radiative transfer models in limb scattering geometry
Evaluation of the new DWD ozone and temperature lidar during the Hohenpeißenberg Ozone Profiling Study (HOPS) and comparison of results with previous NDACC campaigns
A method for random uncertainties validation and probing the natural variability with application to TROPOMI on board Sentinel-5P total ozone measurements
The world Brewer reference triad – updated performance assessment and new double triad
Intercomparison of arctic XH2O observations from three ground-based Fourier transform infrared networks and application for satellite validation
Verification of the Atmospheric Infrared Sounder (AIRS) and the Microwave Limb Sounder (MLS) ozone algorithms based on retrieved daytime and night-time ozone
Intercomparison of Total Carbon Column Observing Network (TCCON) data from two Fourier transform spectrometers at Lauder, New Zealand
Model estimations of geophysical variability between satellite measurements of ozone profiles
Multiscale observations of NH3 around Toronto, Canada
Assessment of the TROPOMI tropospheric NO2 product based on airborne APEX observations
Formaldehyde total column densities over Mexico City: comparison between multi-axis differential optical absorption spectroscopy and solar-absorption Fourier transform infrared measurements
Ground-based validation of the Copernicus Sentinel-5P TROPOMI NO2 measurements with the NDACC ZSL-DOAS, MAX-DOAS and Pandonia global networks
Evaluation of single-footprint AIRS CH4 profile retrieval uncertainties using aircraft profile measurements
Intercomparison of MAX-DOAS vertical profile retrieval algorithms: studies on field data from the CINDI-2 campaign
Validation of SMILES HCl profiles over a wide range from the stratosphere to the lower thermosphere
Comparison of formaldehyde tropospheric columns in Australia and New Zealand using MAX-DOAS, FTIR and TROPOMI
Vivienne H. Payne, Susan S. Kulawik, Emily V. Fischer, Jared F. Brewer, L. Gregory Huey, Kazuyuki Miyazaki, John R. Worden, Kevin W. Bowman, Eric J. Hintsa, Fred Moore, James W. Elkins, and Julieta Juncosa Calahorrano
Atmos. Meas. Tech., 15, 3497–3511, https://doi.org/10.5194/amt-15-3497-2022, https://doi.org/10.5194/amt-15-3497-2022, 2022
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We compare new satellite measurements of peroxyacetyl nitrate (PAN) with reference aircraft measurements from two different instruments flown on the same platform. While there is a systematic difference between the two aircraft datasets, both show the same large-scale distribution of PAN and the discrepancy between aircraft datasets is small compared to the satellite uncertainties. The satellite measurements show skill in capturing large-scale variations in PAN.
William G. Read, Gabriele Stiller, Stefan Lossow, Michael Kiefer, Farahnaz Khosrawi, Dale Hurst, Holger Vömel, Karen Rosenlof, Bianca M. Dinelli, Piera Raspollini, Gerald E. Nedoluha, John C. Gille, Yasuko Kasai, Patrick Eriksson, Christopher E. Sioris, Kaley A. Walker, Katja Weigel, John P. Burrows, and Alexei Rozanov
Atmos. Meas. Tech., 15, 3377–3400, https://doi.org/10.5194/amt-15-3377-2022, https://doi.org/10.5194/amt-15-3377-2022, 2022
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This paper attempts to provide an assessment of the accuracy of 21 satellite-based instruments that remotely measure atmospheric humidity in the upper troposphere of the Earth's atmosphere. The instruments made their measurements from 1984 to the present time; however, most of these instruments began operations after 2000, and only a few are still operational. The objective of this study is to quantify the accuracy of each satellite humidity data set.
Gaia Pinardi, Michel Van Roozendael, François Hendrick, Andreas Richter, Pieter Valks, Ramina Alwarda, Kristof Bognar, Udo Frieß, José Granville, Myojeong Gu, Paul Johnston, Cristina Prados-Roman, Richard Querel, Kimberly Strong, Thomas Wagner, Folkard Wittrock, and Margarita Yela Gonzalez
Atmos. Meas. Tech., 15, 3439–3463, https://doi.org/10.5194/amt-15-3439-2022, https://doi.org/10.5194/amt-15-3439-2022, 2022
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We report on the GOME-2A and GOME-2B OClO dataset (2007 to 2016, from the EUMETSAT's AC SAF) validation using data from nine NDACC zenith-scattered-light DOAS (ZSL-DOAS) instruments distributed in both the Arctic and Antarctic. Specific sensitivity tests are performed on the ground-based data to estimate the impact of the different OClO DOAS analysis settings and their typical errors. Good agreement is found for both the inter-annual variability and the overall OClO seasonal behavior.
Alexandra Laeng, Thomas von Clarmann, Quentin Errera, Udo Grabowski, and Shawn Honomichl
Atmos. Meas. Tech., 15, 2407–2416, https://doi.org/10.5194/amt-15-2407-2022, https://doi.org/10.5194/amt-15-2407-2022, 2022
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In validation exercises, a universal excuse used to explain the residual discrepancy between the data is the natural atmospheric variability due to imperfect co-locations. This work is the first attempt to quantify this atmospheric variability for a large sample of atmospheric constituents and to provide the user with a tool to substract the natural atmospheric variability portion from the residual variability.
Carlos Alberti, Qiansi Tu, Frank Hase, Maria V. Makarova, Konstantin Gribanov, Stefani C. Foka, Vyacheslav Zakharov, Thomas Blumenstock, Michael Buchwitz, Christopher Diekmann, Benjamin Ertl, Matthias M. Frey, Hamud Kh. Imhasin, Dmitry V. Ionov, Farahnaz Khosrawi, Sergey I. Osipov, Maximilian Reuter, Matthias Schneider, and Thorsten Warneke
Atmos. Meas. Tech., 15, 2199–2229, https://doi.org/10.5194/amt-15-2199-2022, https://doi.org/10.5194/amt-15-2199-2022, 2022
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Satellite and ground-based observations at high latitudes are much sparser than at low or mid latitudes, which makes direct coincident comparisons between remote-sensing observations more difficult. Therefore, a method of scaling continuous CAMS model data to the ground-based observations is developed and used for creating virtual COCCON observations. These adjusted CAMS data are then used for satellite inter-comparison, showing good agreement in both Peterhof and Yekaterinburg cities.
Jonas Hachmeister, Oliver Schneising, Michael Buchwitz, Alba Lorente, Tobias Borsdorff, John P. Burrows, Justus Notholt, and Matthias Buschmann
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2022-102, https://doi.org/10.5194/amt-2022-102, 2022
Revised manuscript accepted for AMT
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Sentinel-5P trace gas retrievals rely on elevation data in their calculations. Outdated or inaccurate data can lead to significant errors in e.g. dry-air mole fractions of methane (XCH4). We show that the use of inadequate elevation data leads to strong XCH4 anomalies in Greenland. Similar problems can be expected for regions with inaccurate elevation data or where elevation changes occur (e.g. glaciers melting). We show that updating elevation data used in the retrieval solves this issue.
Takashi Sekiya, Kazuyuki Miyazaki, Henk Eskes, Kengo Sudo, Masayuki Takigawa, and Yugo Kanaya
Atmos. Meas. Tech., 15, 1703–1728, https://doi.org/10.5194/amt-15-1703-2022, https://doi.org/10.5194/amt-15-1703-2022, 2022
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This study gives a systematic comparison of TROPOMI version 1.2 and OMI QA4ECV tropospheric NO2 column through global chemical data assimilation (DA) integration for April–May 2018. DA performance is controlled by measurement sensitivities, retrieval errors, and coverage. Due to reduced errors in TROPOMI, agreements against assimilated and independent observations were improved by TROPOMI DA compared to OMI DA. These results demonstrate that TROPOMI DA improves global analyses of NO2 and ozone.
Claudia Emde, Huan Yu, Arve Kylling, Michel van Roozendael, Kerstin Stebel, Ben Veihelmann, and Bernhard Mayer
Atmos. Meas. Tech., 15, 1587–1608, https://doi.org/10.5194/amt-15-1587-2022, https://doi.org/10.5194/amt-15-1587-2022, 2022
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Retrievals of trace gas concentrations from satellite observations can be affected by clouds in the vicinity, either by shadowing or by scattering of radiation from clouds in the clear region. We used a Monte Carlo radiative transfer model to generate synthetic satellite observations, which we used to test retrieval algorithms and to quantify the error of retrieved NO2 vertical column density due to cloud scattering.
Ellis Remsberg, Murali Natarajan, and Ernest Hilsenrath
Atmos. Meas. Tech., 15, 1521–1535, https://doi.org/10.5194/amt-15-1521-2022, https://doi.org/10.5194/amt-15-1521-2022, 2022
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Ozone (O3) is an excellent tracer of atmospheric transport processes in the middle atmosphere during Arctic winter. The Nimbus 7 LIMS O3 profiles of late October 1978 through May 1979 now extend to the upper mesosphere via its Version 6 (V6) algorithm. We describe the generation of zonal Fourier coefficients from the profiles, followed by their gridding to daily synoptic maps of O3. We then present several examples of how V6 O3 varies in the upper stratosphere and mesosphere during winter.
Dimitris Karagkiozidis, Martina Michaela Friedrich, Steffen Beirle, Alkiviadis Bais, François Hendrick, Kalliopi Artemis Voudouri, Ilias Fountoulakis, Angelos Karanikolas, Paraskevi Tzoumaka, Michel Van Roozendael, Dimitris Balis, and Thomas Wagner
Atmos. Meas. Tech., 15, 1269–1301, https://doi.org/10.5194/amt-15-1269-2022, https://doi.org/10.5194/amt-15-1269-2022, 2022
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In this study we focus on the retrieval of aerosol, NO2, and HCHO vertical profiles from multi-axis differential optical absorption spectroscopy (MAX-DOAS) observations for the first time over Thessaloniki, Greece. We use two independent inversion algorithms for the profile retrievals. We evaluate their performance, we intercompare their results, and we validate their products with ancillary data, measured by other co-located reference instruments.
Patrick E. Sheese, Kaley A. Walker, Chris D. Boone, Adam E. Bourassa, Doug A. Degenstein, Lucien Froidevaux, C. Thomas McElroy, Donal Murtagh, James M. Russell III, and Jiansheng Zou
Atmos. Meas. Tech., 15, 1233–1249, https://doi.org/10.5194/amt-15-1233-2022, https://doi.org/10.5194/amt-15-1233-2022, 2022
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This study analyzes the quality of two versions (v3.6 and v4.1) of ozone concentration measurements from the ACE-FTS (Atmospheric Chemistry Experiment Fourier Transform Spectrometer), by comparing with data from five satellite instruments between 2004 and 2020. It was found that although the v3.6 data exhibit a better agreement than v4.1 with respect to the other instruments, v4.1 exhibits much better stability over time than v3.6. The stability of v4.1 makes it suitable for ozone trend studies.
Jennifer D. Hegarty, Karen E. Cady-Pereira, Vivienne H. Payne, Susan S. Kulawik, John R. Worden, Valentin Kantchev, Helen M. Worden, Kathryn McKain, Jasna V. Pittman, Róisín Commane, Bruce C. Daube Jr., and Eric A. Kort
Atmos. Meas. Tech., 15, 205–223, https://doi.org/10.5194/amt-15-205-2022, https://doi.org/10.5194/amt-15-205-2022, 2022
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Carbon monoxide (CO) is produced by combustion of substances such as fossil fuels and plays an important role in atmospheric pollution and climate. We evaluated estimates of atmospheric CO derived from outgoing radiation measurements of the Atmospheric Infrared Sounder (AIRS) on a satellite orbiting the Earth against CO measurements from aircraft to show that these satellite measurements are reliable for continuous global monitoring of atmospheric CO concentrations.
Amir H. Souri, Kelly Chance, Kang Sun, Xiong Liu, and Matthew S. Johnson
Atmos. Meas. Tech., 15, 41–59, https://doi.org/10.5194/amt-15-41-2022, https://doi.org/10.5194/amt-15-41-2022, 2022
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The central component of satellite and model validation is pointwise measurements. A point is an element of space, whereas satellite (model) pixels represent an averaged area. These two datasets are inherently different. We leveraged some geostatistical tools to transform discrete points to gridded data with quantified uncertainty, comparable to satellite footprint (and response functions). This in part alleviated some complications concerning point–pixel comparisons.
Debora Griffin, Chris A. McLinden, Enrico Dammers, Cristen Adams, Chelsea E. Stockwell, Carsten Warneke, Ilann Bourgeois, Jeff Peischl, Thomas B. Ryerson, Kyle J. Zarzana, Jake P. Rowe, Rainer Volkamer, Christoph Knote, Natalie Kille, Theodore K. Koenig, Christopher F. Lee, Drew Rollins, Pamela S. Rickly, Jack Chen, Lukas Fehr, Adam Bourassa, Doug Degenstein, Katherine Hayden, Cristian Mihele, Sumi N. Wren, John Liggio, Ayodeji Akingunola, and Paul Makar
Atmos. Meas. Tech., 14, 7929–7957, https://doi.org/10.5194/amt-14-7929-2021, https://doi.org/10.5194/amt-14-7929-2021, 2021
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Satellite-derived NOx emissions from biomass burning are estimated with TROPOMI observations. Two common emission estimation methods are applied, and sensitivity tests with model output were performed to determine the accuracy of these methods. The effect of smoke aerosols on TROPOMI NO2 columns is estimated and compared to aircraft observations from four different aircraft campaigns measuring biomass burning plumes in 2018 and 2019 in North America.
Tyler Wizenberg, Kimberly Strong, Kaley Walker, Erik Lutsch, Tobias Borsdorff, and Jochen Landgraf
Atmos. Meas. Tech., 14, 7707–7728, https://doi.org/10.5194/amt-14-7707-2021, https://doi.org/10.5194/amt-14-7707-2021, 2021
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CO is an important atmospheric gas that influences both air quality and the climate. Here, we compare CO measurements from TROPOMI with those from ACE-FTS and an Arctic ground-based FTS at Eureka, Nunavut, to further characterize the accuracy of TROPOMI measurements. CO columns from the instruments agree well but show larger differences at high latitudes. Despite this, the results fall within the TROPOMI accuracy target, indicating good data quality at high latitudes.
Joseph Mendonca, Ray Nassar, Christopher W. O'Dell, Rigel Kivi, Isamu Morino, Justus Notholt, Christof Petri, Kimberly Strong, and Debra Wunch
Atmos. Meas. Tech., 14, 7511–7524, https://doi.org/10.5194/amt-14-7511-2021, https://doi.org/10.5194/amt-14-7511-2021, 2021
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Machine learning has become an important tool for pattern recognition in many applications. In this study, we used a neural network to improve the data quality of OCO-2 measurements made at northern high latitudes. The neural network was trained and used as a binary classifier to filter out bad OCO-2 measurements in order to increase the accuracy and precision of OCO-2 XCO2 measurements in the Boreal and Arctic regions.
Daan Hubert, Klaus-Peter Heue, Jean-Christopher Lambert, Tijl Verhoelst, Marc Allaart, Steven Compernolle, Patrick D. Cullis, Angelika Dehn, Christian Félix, Bryan J. Johnson, Arno Keppens, Debra E. Kollonige, Christophe Lerot, Diego Loyola, Matakite Maata, Sukarni Mitro, Maznorizan Mohamad, Ankie Piters, Fabian Romahn, Henry B. Selkirk, Francisco R. da Silva, Ryan M. Stauffer, Anne M. Thompson, J. Pepijn Veefkind, Holger Vömel, Jacquelyn C. Witte, and Claus Zehner
Atmos. Meas. Tech., 14, 7405–7433, https://doi.org/10.5194/amt-14-7405-2021, https://doi.org/10.5194/amt-14-7405-2021, 2021
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We assess the first 2 years of TROPOMI tropical tropospheric ozone column data. Comparisons to reference measurements by ozonesonde and satellite sensors show that TROPOMI bias (−0.1 to +2.3 DU) and precision (1.5 to 2.5 DU) meet mission requirements. Potential causes of bias and its spatio-temporal structure are discussed, as well as ways to identify sampling errors. Our analysis of known geophysical patterns demonstrates the improved performance of TROPOMI with respect to its predecessors.
Mahesh Kumar Sha, Bavo Langerock, Jean-François L. Blavier, Thomas Blumenstock, Tobias Borsdorff, Matthias Buschmann, Angelika Dehn, Martine De Mazière, Nicholas M. Deutscher, Dietrich G. Feist, Omaira E. García, David W. T. Griffith, Michel Grutter, James W. Hannigan, Frank Hase, Pauli Heikkinen, Christian Hermans, Laura T. Iraci, Pascal Jeseck, Nicholas Jones, Rigel Kivi, Nicolas Kumps, Jochen Landgraf, Alba Lorente, Emmanuel Mahieu, Maria V. Makarova, Johan Mellqvist, Jean-Marc Metzger, Isamu Morino, Tomoo Nagahama, Justus Notholt, Hirofumi Ohyama, Ivan Ortega, Mathias Palm, Christof Petri, David F. Pollard, Markus Rettinger, John Robinson, Sébastien Roche, Coleen M. Roehl, Amelie N. Röhling, Constantina Rousogenous, Matthias Schneider, Kei Shiomi, Dan Smale, Wolfgang Stremme, Kimberly Strong, Ralf Sussmann, Yao Té, Osamu Uchino, Voltaire A. Velazco, Corinne Vigouroux, Mihalis Vrekoussis, Pucai Wang, Thorsten Warneke, Tyler Wizenberg, Debra Wunch, Shoma Yamanouchi, Yang Yang, and Minqiang Zhou
Atmos. Meas. Tech., 14, 6249–6304, https://doi.org/10.5194/amt-14-6249-2021, https://doi.org/10.5194/amt-14-6249-2021, 2021
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This paper presents, for the first time, Sentinel-5 Precursor methane and carbon monoxide validation results covering a period from November 2017 to September 2020. For this study, we used global TCCON and NDACC-IRWG network data covering a wide range of atmospheric and surface conditions across different terrains. We also show the influence of a priori alignment, smoothing uncertainties and the sensitivity of the validation results towards the application of advanced co-location criteria.
Vinod Kumar, Julia Remmers, Steffen Beirle, Joachim Fallmann, Astrid Kerkweg, Jos Lelieveld, Mariano Mertens, Andrea Pozzer, Benedikt Steil, Marc Barra, Holger Tost, and Thomas Wagner
Atmos. Meas. Tech., 14, 5241–5269, https://doi.org/10.5194/amt-14-5241-2021, https://doi.org/10.5194/amt-14-5241-2021, 2021
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We present high-resolution regional atmospheric chemistry model simulations focused around Germany. We highlight the importance of spatial resolution of the model itself as well as the input emissions inventory and short-scale temporal variability of emissions for simulations. We propose a consistent approach for evaluating the simulated vertical distribution of NO2 using MAX-DOAS measurements while also considering its spatial sensitivity volume and change in sensitivity within this volume.
Ralf Zuber, Ulf Köhler, Luca Egli, Mario Ribnitzky, Wolfgang Steinbrecht, and Julian Gröbner
Atmos. Meas. Tech., 14, 4915–4928, https://doi.org/10.5194/amt-14-4915-2021, https://doi.org/10.5194/amt-14-4915-2021, 2021
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We validated two BTS-based systems in a longer-term TOC analysis in the 2019/2020 campaign at Hohenpeißenberg and Davos. The results showed a deviation of the BTS-Solar to Brewers of < 0.1 % with a k = 2 of < 1.5 %. Koherent showed a deviation of 1.7 % with a k = 2 of 2.7 %. Resultingly, the BTS-Solar performance is comparable to Brewers in Hohenpeißenberg. Koherent shows a seasonal variation in Davos due to the sensitivity of its TOC retrieval algorithm to stratospheric temperature.
Susanne Crewell, Kerstin Ebell, Patrick Konjari, Mario Mech, Tatiana Nomokonova, Ana Radovan, David Strack, Arantxa M. Triana-Gómez, Stefan Noël, Raul Scarlat, Gunnar Spreen, Marion Maturilli, Annette Rinke, Irina Gorodetskaya, Carolina Viceto, Thomas August, and Marc Schröder
Atmos. Meas. Tech., 14, 4829–4856, https://doi.org/10.5194/amt-14-4829-2021, https://doi.org/10.5194/amt-14-4829-2021, 2021
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Water vapor (WV) is an important variable in the climate system. Satellite measurements are thus crucial to characterize the spatial and temporal variability in WV and how it changed over time. In particular with respect to the observed strong Arctic warming, the role of WV still needs to be better understood. However, as shown in this paper, a detailed understanding is still hampered by large uncertainties in the various satellite WV products, showing the need for improved methods to derive WV.
René Stübi, Herbert Schill, Eliane Maillard Barras, Jörg Klausen, and Alexander Haefele
Atmos. Meas. Tech., 14, 4203–4217, https://doi.org/10.5194/amt-14-4203-2021, https://doi.org/10.5194/amt-14-4203-2021, 2021
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Total ozone column has been measured since 1926 in the Swiss Alps station Arosa. These worldwide series are based on Dobson sun spectrophotometers. To assure the continuity of these series, a two-stage project was realized at MeteoSwiss: first, Dobson instruments were automated, and then parallel measurements between Arosa and a nearby site in Davos were carried out. The analysis of the data of the manual-to-automated transition and coincident data between the two sites are presented here.
Daniel Zawada, Ghislain Franssens, Robert Loughman, Antti Mikkonen, Alexei Rozanov, Claudia Emde, Adam Bourassa, Seth Dueck, Hannakaisa Lindqvist, Didier Ramon, Vladimir Rozanov, Emmanuel Dekemper, Erkki Kyrölä, John P. Burrows, Didier Fussen, and Doug Degenstein
Atmos. Meas. Tech., 14, 3953–3972, https://doi.org/10.5194/amt-14-3953-2021, https://doi.org/10.5194/amt-14-3953-2021, 2021
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Satellite measurements of atmospheric composition often rely on computer tools known as radiative transfer models to model the propagation of sunlight within the atmosphere. Here we have performed a detailed inter-comparison of seven different radiative transfer models in a variety of conditions. We have found that the models agree remarkably well, at a level better than previously reported. This result provides confidence in our understanding of atmospheric radiative transfer.
Robin Wing, Sophie Godin-Beekmann, Wolfgang Steinbrecht, Thomas J. McGee, John T. Sullivan, Sergey Khaykin, Grant Sumnicht, and Laurence Twigg
Atmos. Meas. Tech., 14, 3773–3794, https://doi.org/10.5194/amt-14-3773-2021, https://doi.org/10.5194/amt-14-3773-2021, 2021
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This paper is a validation study of the newly installed ozone and temperature lidar at Hohenpeißenberg, Germany. As part of the Network for the Detection of Atmospheric Composition Change (NDACC), lidar stations are routinely compared against a travelling reference lidar operated by NASA. We have also attempted to assess potential biases in the reference lidar by comparing the results of this validation campaign with a previous campaign at the Observatoire de Haute-Provence, France.
Viktoria F. Sofieva, Hei Shing Lee, Johanna Tamminen, Christophe Lerot, Fabian Romahn, and Diego G. Loyola
Atmos. Meas. Tech., 14, 2993–3002, https://doi.org/10.5194/amt-14-2993-2021, https://doi.org/10.5194/amt-14-2993-2021, 2021
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Our paper discusses the structure function method, which allows validation of random uncertainties in the data and, at the same time, probing of the small-scale natural variability. We applied this method to the clear-sky total ozone measurements by TROPOMI Sentinel-5P satellite instrument and found that the TROPOMI random error estimation is adequate. The discussed method is a powerful tool, which can be used in various applications.
Xiaoyi Zhao, Vitali Fioletov, Michael Brohart, Volodya Savastiouk, Ihab Abboud, Akira Ogyu, Jonathan Davies, Reno Sit, Sum Chi Lee, Alexander Cede, Martin Tiefengraber, Moritz Müller, Debora Griffin, and Chris McLinden
Atmos. Meas. Tech., 14, 2261–2283, https://doi.org/10.5194/amt-14-2261-2021, https://doi.org/10.5194/amt-14-2261-2021, 2021
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The Brewer spectrophotometer is one of the main instruments for measurements of atmospheric total column ozone. The global Brewer network largely relies on the world reference instruments (the Brewer triad) operated by Environment and Climate Change Canada since the early 1980s. This study provides an updated assessment (1999–2019) of the reference instrument performance, in terms of random uncertainties and long-term stability.
Qiansi Tu, Frank Hase, Thomas Blumenstock, Matthias Schneider, Andreas Schneider, Rigel Kivi, Pauli Heikkinen, Benjamin Ertl, Christopher Diekmann, Farahnaz Khosrawi, Michael Sommer, Tobias Borsdorff, and Uwe Raffalski
Atmos. Meas. Tech., 14, 1993–2011, https://doi.org/10.5194/amt-14-1993-2021, https://doi.org/10.5194/amt-14-1993-2021, 2021
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We compare column-averaged dry-air mole fractions of water vapor (XH2O) retrievals from the COllaborative Carbon Column Observing Network (COCCON) with two co-located ground-based spectrometers as references at two boreal sites. Our study supports the assumption that COCCON also delivers a well-characterized XH2O data product. This is the first published study applying COCCON for MUSICA IASI and TROPOMI validation.
Wannan Wang, Tianhai Cheng, Ronald J. van der A, Jos de Laat, and Jason E. Williams
Atmos. Meas. Tech., 14, 1673–1687, https://doi.org/10.5194/amt-14-1673-2021, https://doi.org/10.5194/amt-14-1673-2021, 2021
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This paper is an evaluation of the AIRS and MLS ozone (O3) algorithms via comparison with daytime and night-time O3 datasets. Results show that further refinements of the AIRS O3 algorithm are required for better surface emissivity retrievals and that cloud cover is another problem that needs to be solved. An inconsistency is found in the
AscDescModeflag of the MLS v4.20 standard O3 product for 90–60° S and 60–90° N, resulting in inconsistent O3 profiles in these regions before May 2015.
David F. Pollard, John Robinson, Hisako Shiona, and Dan Smale
Atmos. Meas. Tech., 14, 1501–1510, https://doi.org/10.5194/amt-14-1501-2021, https://doi.org/10.5194/amt-14-1501-2021, 2021
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This work describes the steps taken to ensure a continuous, high-quality dataset of column-averaged greenhouse gas retrievals from the Total Carbon Column Observing Network (TCCON) site at Lauder, New Zealand, following a change in the Fourier transform spectrometer used to make the measurements from which the retrievals are made.
Patrick E. Sheese, Kaley A. Walker, Chris D. Boone, Doug A. Degenstein, Felicia Kolonjari, David Plummer, Douglas E. Kinnison, Patrick Jöckel, and Thomas von Clarmann
Atmos. Meas. Tech., 14, 1425–1438, https://doi.org/10.5194/amt-14-1425-2021, https://doi.org/10.5194/amt-14-1425-2021, 2021
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Output from climate chemistry models (CMAM, EMAC, and WACCM) is used to estimate the expected geophysical variability of ozone concentrations between coincident satellite instrument measurement times and geolocations. We use the Canadian ACE-FTS and OSIRIS instruments as a case study. Ensemble mean estimates are used to optimize coincidence criteria between the two instruments, allowing for the use of more coincident profiles while providing an estimate of the geophysical variation.
Shoma Yamanouchi, Camille Viatte, Kimberly Strong, Erik Lutsch, Dylan B. A. Jones, Cathy Clerbaux, Martin Van Damme, Lieven Clarisse, and Pierre-Francois Coheur
Atmos. Meas. Tech., 14, 905–921, https://doi.org/10.5194/amt-14-905-2021, https://doi.org/10.5194/amt-14-905-2021, 2021
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Ammonia (NH3) is a major source of pollution in the air. As such, there have been increasing efforts to measure the atmospheric abundance of NH3 and its spatial and temporal variability. In this study, long-term measurements of NH3 over Toronto, Canada, derived from multiscale datasets are examined. These NH3 datasets were compared to each other and to a model to better understand NH3 variability and to assess model performance.
Frederik Tack, Alexis Merlaud, Marian-Daniel Iordache, Gaia Pinardi, Ermioni Dimitropoulou, Henk Eskes, Bart Bomans, Pepijn Veefkind, and Michel Van Roozendael
Atmos. Meas. Tech., 14, 615–646, https://doi.org/10.5194/amt-14-615-2021, https://doi.org/10.5194/amt-14-615-2021, 2021
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We assess the TROPOMI tropospheric NO2 product (OFFL v1.03.01; 3.5 km × 7 km at nadir observations) based on coinciding airborne APEX reference observations (~75 m × 120 m), acquired over polluted regions in Belgium. The TROPOMI NO2 product meets the mission requirements in terms of precision and accuracy. However, we show that TROPOMI is biased low over polluted areas, mainly due to the limited spatial resolution of a priori input for the AMF computation.
Claudia Rivera Cárdenas, Cesar Guarín, Wolfgang Stremme, Martina M. Friedrich, Alejandro Bezanilla, Diana Rivera Ramos, Cristina A. Mendoza-Rodríguez, Michel Grutter, Thomas Blumenstock, and Frank Hase
Atmos. Meas. Tech., 14, 595–613, https://doi.org/10.5194/amt-14-595-2021, https://doi.org/10.5194/amt-14-595-2021, 2021
Tijl Verhoelst, Steven Compernolle, Gaia Pinardi, Jean-Christopher Lambert, Henk J. Eskes, Kai-Uwe Eichmann, Ann Mari Fjæraa, José Granville, Sander Niemeijer, Alexander Cede, Martin Tiefengraber, François Hendrick, Andrea Pazmiño, Alkiviadis Bais, Ariane Bazureau, K. Folkert Boersma, Kristof Bognar, Angelika Dehn, Sebastian Donner, Aleksandr Elokhov, Manuel Gebetsberger, Florence Goutail, Michel Grutter de la Mora, Aleksandr Gruzdev, Myrto Gratsea, Georg H. Hansen, Hitoshi Irie, Nis Jepsen, Yugo Kanaya, Dimitris Karagkiozidis, Rigel Kivi, Karin Kreher, Pieternel F. Levelt, Cheng Liu, Moritz Müller, Monica Navarro Comas, Ankie J. M. Piters, Jean-Pierre Pommereau, Thierry Portafaix, Cristina Prados-Roman, Olga Puentedura, Richard Querel, Julia Remmers, Andreas Richter, John Rimmer, Claudia Rivera Cárdenas, Lidia Saavedra de Miguel, Valery P. Sinyakov, Wolfgang Stremme, Kimberly Strong, Michel Van Roozendael, J. Pepijn Veefkind, Thomas Wagner, Folkard Wittrock, Margarita Yela González, and Claus Zehner
Atmos. Meas. Tech., 14, 481–510, https://doi.org/10.5194/amt-14-481-2021, https://doi.org/10.5194/amt-14-481-2021, 2021
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This paper reports on the ground-based validation of the NO2 data produced operationally by the TROPOMI instrument on board the Sentinel-5 Precursor satellite. Tropospheric, stratospheric, and total NO2 columns are compared to measurements collected from MAX-DOAS, ZSL-DOAS, and PGN/Pandora instruments respectively. The products are found to satisfy mission requirements in general, though negative mean differences are found at sites with high pollution levels. Potential causes are discussed.
Susan S. Kulawik, John R. Worden, Vivienne H. Payne, Dejian Fu, Steven C. Wofsy, Kathryn McKain, Colm Sweeney, Bruce C. Daube Jr., Alan Lipton, Igor Polonsky, Yuguang He, Karen E. Cady-Pereira, Edward J. Dlugokencky, Daniel J. Jacob, and Yi Yin
Atmos. Meas. Tech., 14, 335–354, https://doi.org/10.5194/amt-14-335-2021, https://doi.org/10.5194/amt-14-335-2021, 2021
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This paper shows comparisons of a new single-footprint methane product from the AIRS satellite to aircraft-based observations. We show that this AIRS methane product provides useful information to study seasonal and global methane trends of this important greenhouse gas.
Jan-Lukas Tirpitz, Udo Frieß, François Hendrick, Carlos Alberti, Marc Allaart, Arnoud Apituley, Alkis Bais, Steffen Beirle, Stijn Berkhout, Kristof Bognar, Tim Bösch, Ilya Bruchkouski, Alexander Cede, Ka Lok Chan, Mirjam den Hoed, Sebastian Donner, Theano Drosoglou, Caroline Fayt, Martina M. Friedrich, Arnoud Frumau, Lou Gast, Clio Gielen, Laura Gomez-Martín, Nan Hao, Arjan Hensen, Bas Henzing, Christian Hermans, Junli Jin, Karin Kreher, Jonas Kuhn, Johannes Lampel, Ang Li, Cheng Liu, Haoran Liu, Jianzhong Ma, Alexis Merlaud, Enno Peters, Gaia Pinardi, Ankie Piters, Ulrich Platt, Olga Puentedura, Andreas Richter, Stefan Schmitt, Elena Spinei, Deborah Stein Zweers, Kimberly Strong, Daan Swart, Frederik Tack, Martin Tiefengraber, René van der Hoff, Michel van Roozendael, Tim Vlemmix, Jan Vonk, Thomas Wagner, Yang Wang, Zhuoru Wang, Mark Wenig, Matthias Wiegner, Folkard Wittrock, Pinhua Xie, Chengzhi Xing, Jin Xu, Margarita Yela, Chengxin Zhang, and Xiaoyi Zhao
Atmos. Meas. Tech., 14, 1–35, https://doi.org/10.5194/amt-14-1-2021, https://doi.org/10.5194/amt-14-1-2021, 2021
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Multi-axis differential optical absorption spectroscopy (MAX-DOAS) is a ground-based remote sensing measurement technique that derives atmospheric aerosol and trace gas vertical profiles from skylight spectra. In this study, consistency and reliability of MAX-DOAS profiles are assessed by applying nine different evaluation algorithms to spectral data recorded during an intercomparison campaign in the Netherlands and by comparing the results to colocated supporting observations.
Seidai Nara, Tomohiro O. Sato, Takayoshi Yamada, Tamaki Fujinawa, Kota Kuribayashi, Takeshi Manabe, Lucien Froidevaux, Nathaniel J. Livesey, Kaley A. Walker, Jian Xu, Franz Schreier, Yvan J. Orsolini, Varavut Limpasuvan, Nario Kuno, and Yasuko Kasai
Atmos. Meas. Tech., 13, 6837–6852, https://doi.org/10.5194/amt-13-6837-2020, https://doi.org/10.5194/amt-13-6837-2020, 2020
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In the atmosphere, more than 80 % of chlorine compounds are anthropogenic. Hydrogen chloride (HCl), the main stratospheric chlorine reservoir, is useful to estimate the total budget of the atmospheric chlorine compounds. We report, for the first time, the HCl vertical distribution from the middle troposphere to the lower thermosphere using a high-sensitivity SMILES measurement; the data quality is quantified by comparisons with other measurements and via theoretical error analysis.
Robert G. Ryan, Jeremy D. Silver, Richard Querel, Dan Smale, Steve Rhodes, Matt Tully, Nicholas Jones, and Robyn Schofield
Atmos. Meas. Tech., 13, 6501–6519, https://doi.org/10.5194/amt-13-6501-2020, https://doi.org/10.5194/amt-13-6501-2020, 2020
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Models have identified Australasia as a formaldehyde (HCHO) hotspot from vegetation sources, but few measurement studies exist to verify this. We compare, and find good agreement between, HCHO measurements using three – two ground-based and one satellite-based – different spectroscopic techniques in Australia and New Zealand. This gives confidence in using satellite observations to study HCHO and associated air chemistry and pollution problems in this under-studied part of the world.