Articles | Volume 3, issue 2
03 Mar 2010
03 Mar 2010
Continuous quality assessment of atmospheric water vapour measurement techniques: FTIR, Cimel, MFRSR, GPS, and Vaisala RS92
M. Schneider et al.
Related subject area
Subject: Gases | Technique: Remote Sensing | Topic: Validation and IntercomparisonsAssessment of the TROPOMI tropospheric NO2 product based on airborne APEX observationsFormaldehyde total column densities over Mexico City: comparison between multi-axis differential optical absorption spectroscopy and solar-absorption Fourier transform infrared measurementsGround-based validation of the Copernicus Sentinel-5P TROPOMI NO2 measurements with the NDACC ZSL-DOAS, MAX-DOAS and Pandonia global networksEvaluation of single-footprint AIRS CH4 profile retrieval uncertainties using aircraft profile measurementsIntercomparison of MAX-DOAS vertical profile retrieval algorithms: studies on field data from the CINDI-2 campaignValidation of SMILES HCl profiles over a wide range from the stratosphere to the lower thermosphereComparison of formaldehyde tropospheric columns in Australia and New Zealand using MAX-DOAS, FTIR and TROPOMIValidation of tropospheric NO2 column measurements of GOME-2A and OMI using MAX-DOAS and direct sun network observationsEvaluating Sentinel-5P TROPOMI tropospheric NO2 column densities with airborne and Pandora spectrometers near New York City and Long Island SoundIntercomparison and evaluation of ground- and satellite-based stratospheric ozone and temperature profiles above Observatoire de Haute-Provence during the Lidar Validation NDACC Experiment (LAVANDE)Satellite validation strategy assessments based on the AROMAT campaignsIntercomparison of TCCON data from two Fourier transform spectrometers at Lauder, New ZealandA tropopause-related climatological a priori profile for IASI-SOFRID ozone retrievals: improvements and validationValidation of TROPOMI tropospheric NO2 columns using dual-scan multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements in Uccle, BrusselsValidation of XCO2 and XCH4 retrieved from a portable Fourier transform spectrometer with those from in situ profiles from aircraft-borne instrumentsInter-comparison of MAX-DOAS measurements of tropospheric HONO slant column densities and vertical profiles during the CINDI-2 campaignQuality controls, bias, and seasonality of CO2 columns in the boreal forest with Orbiting Carbon Observatory-2, Total Carbon Column Observing Network, and EM27/SUN measurementsIntercomparison of Arctic ground-based XH2O observations from COCCON, TCCON and NDACC, and application of COCCON XH2O for IASI and TROPOMI validationRecovery and validation of Odin/SMR long-term measurements of mesospheric carbon monoxide1.5 years of TROPOMI CO measurements: comparisons to MOPITT and ATomIntercomparison of atmospheric CO2 and CH4 abundances on regional scales in boreal areas using Copernicus Atmosphere Monitoring Service (CAMS) analysis, COllaborative Carbon Column Observing Network (COCCON) spectrometers, and Sentinel-5 Precursor satellite observationsMultiscale observations of NH3 around Toronto, CanadaIn-orbit Earth reflectance validation of TROPOMI on board the Sentinel-5 Precursor satelliteMethane and nitrous oxide from ground-based FTIR at Addis Ababa: observations, error analysis, and comparison with satellite dataOn the performance of satellite-based observations of XCO2 in capturing the NOAA Carbon Tracker model and ground-based flask observations over Africa's land massModel estimations of geophysical variability between satellite measurements of ozone profilesTROPOMI–Sentinel-5 Precursor formaldehyde validation using an extensive network of ground-based Fourier-transform infrared stationsImpact of land–water sensitivity contrast on MOPITT retrievals and trends over a coastal cityVerification of the AIRS and MLS ozone algorithms based on retrieved daytime and nighttime ozoneModel-based climatology of diurnal variability in stratospheric ozone as a data analysis toolTotal column water vapour retrieval from S-5P/TROPOMI in the visible blue spectral rangeAssessment of NO2 observations during DISCOVER-AQ and KORUS-AQ field campaignsIntercomparison of NO2, O4, O3 and HCHO slant column measurements by MAX-DOAS and zenith-sky UV–visible spectrometers during CINDI-2Assessment of the quality of TROPOMI high-spatial-resolution NO2 data products in the Greater Toronto AreaValidation of acetonitrile (CH3CN) measurements in the stratosphere and lower mesosphere from the SMILES instrument on the International Space StationComparison of optimal estimation HDO∕H2O retrievals from AIRS with ORACLES measurementsComparison of GTO-ECV and adjusted MERRA-2 total ozone columns from the last 2 decades and assessment of interannual variabilityShipborne MAX-DOAS measurements for validation of TROPOMI NO2 productsAssessing Measurements of Pollution in the Troposphere (MOPITT) carbon monoxide retrievals over urban versus non-urban regionsEarly results and validation of SAGE III-ISS ozone profile measurements from onboard the International Space StationValidation of MAX-DOAS retrievals of aerosol extinction, SO2, and NO2 through comparison with lidar, sun photometer, active DOAS, and aircraft measurements in the Athabasca oil sands regionTemperature and water vapour measurements in the framework of the Network for the Detection of Atmospheric Composition Change (NDACC)A reassessment of the discrepancies in the annual variation of δD-H2O in the tropical lower stratosphere between the MIPAS and ACE-FTS satellite data setsComparison of TROPOMI/Sentinel-5 Precursor NO2 observations with ground-based measurements in HelsinkiEvaluating the impact of spatial resolution on tropospheric NO2 column comparisons within urban areas using high-resolution airborne dataTCCON and NDACC XCO measurements: difference, discussion and applicationUnderestimation of column NO2 amounts from the OMI satellite compared to diurnally varying ground-based retrievals from multiple PANDORA spectrometer instrumentsEvaluation of MOPITT Version 7 joint TIR–NIR XCO retrievals with TCCONTROPOMI/S5P total ozone column data: global ground-based validation and consistency with other satellite missionsQuantifying CH4 emissions from hard coal mines using mobile sun-viewing Fourier transform spectrometry
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,Short summary
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,
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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.
Gaia Pinardi, Michel Van Roozendael, François Hendrick, Nicolas Theys, Nader Abuhassan, Alkiviadis Bais, Folkert Boersma, Alexander Cede, Jihyo Chong, Sebastian Donner, Theano Drosoglou, Anatoly Dzhola, Henk Eskes, Udo Frieß, José Granville, Jay R. Herman, Robert Holla, Jari Hovila, Hitoshi Irie, Yugo Kanaya, Dimitris Karagkiozidis, Natalia Kouremeti, Jean-Christopher Lambert, Jianzhong Ma, Enno Peters, Ankie Piters, Oleg Postylyakov, Andreas Richter, Julia Remmers, Hisahiro Takashima, Martin Tiefengraber, Pieter Valks, Tim Vlemmix, Thomas Wagner, and Folkard Wittrock
Atmos. Meas. Tech., 13, 6141–6174,Short summary
We validate several GOME-2 and OMI tropospheric NO2 products with 23 MAX-DOAS and 16 direct sun instruments distributed worldwide, highlighting large horizontal inhomogeneities at several sites affecting the validation results. We propose a method for quantification and correction. We show the application of such correction reduces the satellite underestimation in almost all heterogeneous cases, but a negative bias remains over the MAX-DOAS and direct sun network ensemble for both satellites.
Laura M. Judd, Jassim A. Al-Saadi, James J. Szykman, Lukas C. Valin, Scott J. Janz, Matthew G. Kowalewski, Henk J. Eskes, J. Pepijn Veefkind, Alexander Cede, Moritz Mueller, Manuel Gebetsberger, Robert Swap, R. Bradley Pierce, Caroline R. Nowlan, Gonzalo González Abad, Amin Nehrir, and David Williams
Atmos. Meas. Tech., 13, 6113–6140,Short summary
This paper evaluates Sentinel-5P TROPOMI v1.2 NO2 tropospheric columns over New York City using data from airborne mapping spectrometers and a network of ground-based spectrometers (Pandora) collected in 2018. These evaluations consider impacts due to cloud parameters, a priori profile assumptions, and spatial and temporal variability. Overall, TROPOMI tropospheric NO2 columns appear to have a low bias in this region.
Robin Wing, Wolfgang Steinbrecht, Sophie Godin-Beekmann, Thomas J. McGee, John T. Sullivan, Grant Sumnicht, Gérard Ancellet, Alain Hauchecorne, Sergey Khaykin, and Philippe Keckhut
Atmos. Meas. Tech., 13, 5621–5642,Short summary
A lidar intercomparison campaign was conducted over a period of 28 nights at Observatoire de Haute-Provence (OHP) in 2017 and 2018. The objective is to validate the ozone and temperature profiles at OHP to ensure the quality of data submitted to the NDACC database remains high. A mobile reference lidar operated by NASA was transported to OHP and operated concurrently with the French lidars. Agreement for ozone was better than 5 % between 20 and 40 km, and temperatures were equal within 3 K.
Alexis Merlaud, Livio Belegante, Daniel-Eduard Constantin, Mirjam Den Hoed, Andreas Carlos Meier, Marc Allaart, Magdalena Ardelean, Maxim Arseni, Tim Bösch, Hugues Brenot, Andreea Calcan, Emmanuel Dekemper, Sebastian Donner, Steffen Dörner, Mariana Carmelia Balanica Dragomir, Lucian Georgescu, Anca Nemuc, Doina Nicolae, Gaia Pinardi, Andreas Richter, Adrian Rosu, Thomas Ruhtz, Anja Schönhardt, Dirk Schuettemeyer, Reza Shaiganfar, Kerstin Stebel, Frederik Tack, Sorin Nicolae Vâjâiac, Jeni Vasilescu, Jurgen Vanhamel, Thomas Wagner, and Michel Van Roozendael
Atmos. Meas. Tech., 13, 5513–5535,Short summary
The AROMAT campaigns took place in Romania in 2014 and 2015. They aimed to test airborne observation systems dedicated to air quality studies and to verify the concept of such campaigns in support of the validation of space-borne atmospheric missions. We show that airborne measurements of NO2 can be valuable for the validation of air quality satellites. For H2CO and SO2, the validation should involve ground-based measurement systems at key locations that the AROMAT measurements help identify.
David F. Pollard, John Robinson, Hisako Shiona, and Dan Smale
Atmos. Meas. Tech. Discuss.,
Revised manuscript accepted for AMTShort summary
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 of the Fourier transform spectrometer used to make the measurements from which the retrievals are made.
Brice Barret, Emanuele Emili, and Eric Le Flochmoen
Atmos. Meas. Tech., 13, 5237–5257,Short summary
The IASI satellite sensor is used to document the variability and evolution of tropospheric ozone (O3). IASI O3 retrievals generally use a single a priori profile which can be responsible for biases and too-low variability. We have therefore implemented a dynamical a priori profile based on pixel location, month and tropopause height. Comparison with 10 years of global ozonesonde profiles shows large improvements in the retrieved tropospheric O3, with biases corrected and enhanced variabilities.
Ermioni Dimitropoulou, François Hendrick, Gaia Pinardi, Martina M. Friedrich, Alexis Merlaud, Frederik Tack, Helene De Longueville, Caroline Fayt, Christian Hermans, Quentin Laffineur, Frans Fierens, and Michel Van Roozendael
Atmos. Meas. Tech., 13, 5165–5191,Short summary
We present 1 year of dual-scan ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements of aerosol and tropospheric NO2 in Uccle (Belgium). Measuring tropospheric NO2 vertical column densities (VCDs) in different azimuthal directions has a positive effect on comparison with measurements from TROPOMI. We prove that the use of inadequate a priori NO2 profile shape data in the TROPOMI retrieval is responsible for the systematic underestimation of S5P NO2 data.
Hirofumi Ohyama, Isamu Morino, Voltaire A. Velazco, Theresa Klausner, Gerry Bagtasa, Matthäus Kiel, Matthias Frey, Akihiro Hori, Osamu Uchino, Tsuneo Matsunaga, Nicholas M. Deutscher, Joshua P. DiGangi, Yonghoon Choi, Glenn S. Diskin, Sally E. Pusede, Alina Fiehn, Anke Roiger, Michael Lichtenstern, Hans Schlager, Pao K. Wang, Charles C.-K. Chou, Maria Dolores Andrés-Hernández, and John P. Burrows
Atmos. Meas. Tech., 13, 5149–5163,Short summary
Column-averaged dry-air mole fractions of CO2 and CH4 measured by a solar viewing portable Fourier transform spectrometer (EM27/SUN) were validated with in situ profile data obtained during the transfer flights of two aircraft campaigns. Atmospheric dynamical properties based on ERA5 and WRF-Chem were used as criteria for selecting the best aircraft profiles for the validation. The resulting air-mass-independent correction factors for the EM27/SUN data were 0.9878 for CO2 and 0.9829 for CH4.
Yang Wang, Arnoud Apituley, Alkiviadis Bais, Steffen Beirle, Nuria Benavent, Alexander Borovski, Ilya Bruchkouski, Ka Lok Chan, Sebastian Donner, Theano Drosoglou, Henning Finkenzeller, Martina M. Friedrich, Udo Frieß, David Garcia-Nieto, Laura Gómez-Martín, François Hendrick, Andreas Hilboll, Junli Jin, Paul Johnston, Theodore K. Koenig, Karin Kreher, Vinod Kumar, Aleksandra Kyuberis, Johannes Lampel, Cheng Liu, Haoran Liu, Jianzhong Ma, Oleg L. Polyansky, Oleg Postylyakov, Richard Querel, Alfonso Saiz-Lopez, Stefan Schmitt, Xin Tian, Jan-Lukas Tirpitz, Michel Van Roozendael, Rainer Volkamer, Zhuoru Wang, Pinhua Xie, Chengzhi Xing, Jin Xu, Margarita Yela, Chengxin Zhang, and Thomas Wagner
Atmos. Meas. Tech., 13, 5087–5116,
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,Short summary
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.
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. Discuss.,
Revised manuscript accepted for AMTShort summary
We compare column-averaged dry-air mole fractions of water vapor (XH2O) retrievals from COCCON (COllaborative Carbon Column Observing Network) 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 for applying COCCON for MUSICA IASI and TROPOMI validation.
Francesco Grieco, Kristell Pérot, Donal Murtagh, Patrick Eriksson, Peter Forkman, Bengt Rydberg, Bernd Funke, Kaley A. Walker, and Hugh C. Pumphrey
Atmos. Meas. Tech., 13, 5013–5031,Short summary
We present a unique – by time extension and geographical coverage – dataset of satellite observations of carbon monoxide (CO) in the mesosphere which will allow us to study dynamical processes, since CO is a very good tracer of circulation in the mesosphere. Previously, the dataset was unusable due to instrumental artefacts that affected the measurements. We identify the cause of the artefacts, eliminate them and prove the quality of the results by comparing with other instrument measurements.
Sara Martínez-Alonso, Merritt Deeter, Helen Worden, Tobias Borsdorff, Ilse Aben, Róisin Commane, Bruce Daube, Gene Francis, Maya George, Jochen Landgraf, Debbie Mao, Kathryn McKain, and Steven Wofsy
Atmos. Meas. Tech., 13, 4841–4864,Short summary
CO is of great importance in climate and air quality studies. To understand newly available TROPOMI data in the frame of the global CO record, we compared those to satellite (MOPITT) and airborne (ATom) CO datasets. The MOPITT dataset is the longest to date (2000–present) and is well-characterized. We used ATom to validate cloudy TROPOMI data over oceans and investigate TROPOMI's vertical sensitivity to CO. Our results show that TROPOMI CO data are in excellent agreement with the other datasets.
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,Short summary
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.
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. Discuss.,
Revised manuscript accepted for AMTShort summary
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 against each other, and against a model to better understand NH3 variability, and to assess model performance.
Lieuwe G. Tilstra, Martin de Graaf, Ping Wang, and Piet Stammes
Atmos. Meas. Tech., 13, 4479–4497,Short summary
The goal of the study was to determine the accuracy of the radiometric calibration of the TROPOMI instrument on board the Sentinel-5 Precursor satellite in flight. The Earth reflectances were compared to radiative transfer calculations. We report calibration accuracies and errors for 21 selected wavelength bands between 328 and 2314 nm, located in TROPOMI spectral bands 3–7. The reported numbers can be used to perform corrections that will benefit the retrievals of many atmospheric properties.
Temesgen Yirdaw Berhe, Gizaw Mengistu Tsidu, Thomas Blumenstock, Frank Hase, and Gabriele P. Stiller
Atmos. Meas. Tech., 13, 4079–4096,Short summary
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.
Anteneh Getachew Mengistu and Gizaw Mengistu Tsidu
Atmos. Meas. Tech., 13, 4009–4033,Short summary
This paper assesses the performance of observed XCO2 from the GOSAT and OCO-2 satellites in capturing simulated XCO2 from the NOAA Carbon Tracker model over Africa. These satellite observations and Carbon Tracker mixing ratios near the surface are also compared to available in situ CO2 flask data from Assekrem, Algeria; Mt. Kenya; Gobabeb, Namibia; and Cape Town; as well as to data off the coast at Seychelles, Ascension Island, and at Izana, Tenerife.
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. Discuss.,
Revised manuscript accepted for AMT
Corinne Vigouroux, Bavo Langerock, Carlos Augusto Bauer Aquino, Thomas Blumenstock, Zhibin Cheng, Martine De Mazière, Isabelle De Smedt, Michel Grutter, James W. Hannigan, Nicholas Jones, Rigel Kivi, Diego Loyola, Erik Lutsch, Emmanuel Mahieu, Maria Makarova, Jean-Marc Metzger, Isamu Morino, Isao Murata, Tomoo Nagahama, Justus Notholt, Ivan Ortega, Mathias Palm, Gaia Pinardi, Amelie Röhling, Dan Smale, Wolfgang Stremme, Kim Strong, Ralf Sussmann, Yao Té, Michel van Roozendael, Pucai Wang, and Holger Winkler
Atmos. Meas. Tech., 13, 3751–3767,Short summary
We validate the TROPOMI HCHO product with ground-based FTIR (Fourier-transform infrared) measurements from 25 stations. We find that TROPOMI overestimates HCHO under clean conditions, while it underestimates it at high HCHO levels. Both TROPOMI precision and accuracy reach the pre-launch requirements, and its precision can even be 2 times better. The observed TROPOMI seasonal variability is in agreement with the FTIR data. The TROPOMI random uncertainty and data filtering should be refined.
Ian Ashpole and Aldona Wiacek
Atmos. Meas. Tech., 13, 3521–3542,Short summary
We analyse temporal trends in carbon monoxide (CO) detected by the MOPITT satellite instrument over the coastal city of Halifax, Canada. We show that trends in surface level CO differ significantly depending on the data product used (Level 2 or Level 3). This is linked to the different sensitivity with which MOPITT can detect CO at the surface over land and water as well as the differing degree to which the data can be filtered to account for this in the different products.
Wannan Wang, Tianhai Cheng, Ronald van der A, Jos de Laat, and Jason E. Williams
Atmos. Meas. Tech. Discuss.,
Revised manuscript accepted for AMTShort summary
The scope of the paper is the evaluation of the AIRS and MLS ozone algorithms via comparison with daytime and nighttime ozone datasets. Results show further refinements of AIRS ozone algorithm for better surface emissivity retrievals are required and cloud covers is another problem that needs to be solved. An inconsistency is found in the ‘AscDescMode’ flag of MLS v4.20 standard O3 product in 90° S–60° S and 60° N–90° N, resulting in inconsistent ozone profiles in these regions before May 2015.
Stacey M. Frith, Pawan K. Bhartia, Luke D. Oman, Natalya A. Kramarova, Richard D. McPeters, and Gordon J. Labow
Atmos. Meas. Tech., 13, 2733–2749,Short summary
We use the NASA GEOS-GMI chemistry climate model to construct a climatology of stratospheric ozone diurnal variations as a function of latitude, pressure and month, which can be used in a variety of data analysis tasks involving ozone observations made at different times of the day. The climatology compares well with previous modeling simulations and available observations, and to the authors' knowledge is the first characterization of the diurnal cycle available for general ozone data analyses.
Christian Borger, Steffen Beirle, Steffen Dörner, Holger Sihler, and Thomas Wagner
Atmos. Meas. Tech., 13, 2751–2783,Short summary
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 %.
Sungyeon Choi, Lok N. Lamsal, Melanie Follette-Cook, Joanna Joiner, Nickolay A. Krotkov, William H. Swartz, Kenneth E. Pickering, Christopher P. Loughner, Wyat Appel, Gabriele Pfister, Pablo E. Saide, Ronald C. Cohen, Andrew J. Weinheimer, and Jay R. Herman
Atmos. Meas. Tech., 13, 2523–2546,
Karin Kreher, Michel Van Roozendael, Francois Hendrick, Arnoud Apituley, Ermioni Dimitropoulou, Udo Frieß, Andreas Richter, Thomas Wagner, Johannes Lampel, Nader Abuhassan, Li Ang, Monica Anguas, Alkis Bais, Nuria Benavent, Tim Bösch, Kristof Bognar, Alexander Borovski, Ilya Bruchkouski, Alexander Cede, Ka Lok Chan, Sebastian Donner, Theano Drosoglou, Caroline Fayt, Henning Finkenzeller, David Garcia-Nieto, Clio Gielen, Laura Gómez-Martín, Nan Hao, Bas Henzing, Jay R. Herman, Christian Hermans, Syedul Hoque, Hitoshi Irie, Junli Jin, Paul Johnston, Junaid Khayyam Butt, Fahim Khokhar, Theodore K. Koenig, Jonas Kuhn, Vinod Kumar, Cheng Liu, Jianzhong Ma, Alexis Merlaud, Abhishek K. Mishra, Moritz Müller, Monica Navarro-Comas, Mareike Ostendorf, Andrea Pazmino, Enno Peters, Gaia Pinardi, Manuel Pinharanda, Ankie Piters, Ulrich Platt, Oleg Postylyakov, Cristina Prados-Roman, Olga Puentedura, Richard Querel, Alfonso Saiz-Lopez, Anja Schönhardt, Stefan F. Schreier, André Seyler, Vinayak Sinha, Elena Spinei, Kimberly Strong, Frederik Tack, Xin Tian, Martin Tiefengraber, Jan-Lukas Tirpitz, Jeroen van Gent, Rainer Volkamer, Mihalis Vrekoussis, Shanshan Wang, Zhuoru Wang, Mark Wenig, Folkard Wittrock, Pinhua H. Xie, Jin Xu, Margarita Yela, Chengxin Zhang, and Xiaoyi Zhao
Atmos. Meas. Tech., 13, 2169–2208,Short summary
In September 2016, 36 spectrometers from 24 institutes measured a number of key atmospheric pollutants during an instrument intercomparison campaign (CINDI-2) at Cabauw, the Netherlands. Here we report on the outcome of this intercomparison exercise. The three major goals were to characterise the differences between the participating instruments, to define a robust methodology for performance assessment, and to contribute to the harmonisation of the measurement settings and retrieval methods.
Xiaoyi Zhao, Debora Griffin, Vitali Fioletov, Chris McLinden, Alexander Cede, Martin Tiefengraber, Moritz Müller, Kristof Bognar, Kimberly Strong, Folkert Boersma, Henk Eskes, Jonathan Davies, Akira Ogyu, and Sum Chi Lee
Atmos. Meas. Tech., 13, 2131–2159,Short summary
Pandora NO2 measurements made at three sites located in the Toronto area are used to evaluate the TROPOspheric Monitoring Instrument (TROPOMI) NO2 data products, including standard NO2 and research data developed using a high-resolution regional air quality forecast model. TROPOMI pixels located upwind and downwind from the Pandora sites were analyzed by a new wind-based validation method, which revealed the spatial patterns of local and transported emissions and regional air quality changes.
Tamaki Fujinawa, Tomohiro O. Sato, Takayoshi Yamada, Seidai Nara, Yuki Uchiyama, Kodai Takahashi, Naohiro Yoshida, and Yasuko Kasai
Atmos. Meas. Tech., 13, 2119–2129,Short summary
We performed an error analysis of SMILES observations for acetonitrile and a validation using the MLS observations by extracting the coincident points between SMILES and MLS data. The major error sources for the SMILES observations were quantitatively estimated. At upper pressure levels the difference between the two datasets increased because of an uncertainty in MLS observations. The results showed that SMILES has an advantage in measuring acetonitrile in the upper stratosphere and mesosphere.
Robert L. Herman, John Worden, David Noone, Dean Henze, Kevin Bowman, Karen Cady-Pereira, Vivienne H. Payne, Susan S. Kulawik, and Dejian Fu
Atmos. Meas. Tech., 13, 1825–1834,Short summary
This study is the first assessment and validation of AIRS HDO / H2O retrieved by optimal estimation. Initial comparisons with in situ measurements from NASA ORACLES are promising: the small bias and consistent rms of AIRS suggest that AIRS has well-characterized HDO / H2O. This analysis opens the possibility of a new 17-year long-term data record of global tropospheric HDO / H2O measured from space.
Melanie Coldewey-Egbers, Diego G. Loyola, Gordon Labow, and Stacey M. Frith
Atmos. Meas. Tech., 13, 1633–1654,Short summary
We compare total ozone columns from the satellite-based GOME-type Total Ozone Essential Climate Variable record and the adjusted Modern Era Retrospective Analysis for Research and Applications version 2 reanalysis during their overlap period from 1995 to 2018. Ozone columns and anomalies show a very good agreement in terms of spatial and temporal patterns. In the tropics the interannual variability is assessed by means of an EOF analysis and both data records show a remarkable consistency.
Ping Wang, Ankie Piters, Jos van Geffen, Olaf Tuinder, Piet Stammes, and Stefan Kinne
Atmos. Meas. Tech., 13, 1413–1426,Short summary
The comparison of shipborne MAX-DOAS and TROPOMI NO2 products is important for the evaluation of the TROPOMI products. The ship cruises were mainly over remote oceans, thus we only measured background tropospheric NO2. Stratospheric NO2 was measured more accurately because there was almost no contamination from tropospheric NO2. We found that the TROPOMI stratospheric NO2 vertical column densities were slightly higher than the MAX-DOAS measurements.
Wenfu Tang, Helen M. Worden, Merritt N. Deeter, David P. Edwards, Louisa K. Emmons, Sara Martínez-Alonso, Benjamin Gaubert, Rebecca R. Buchholz, Glenn S. Diskin, Russell R. Dickerson, Xinrong Ren, Hao He, and Yutaka Kondo
Atmos. Meas. Tech., 13, 1337–1356,
M. Patrick McCormick, Liqiao Lei, Michael T. Hill, John Anderson, Richard Querel, and Wolfgang Steinbrecht
Atmos. Meas. Tech., 13, 1287–1297,Short summary
We present a validation of O3 data from the SAGE III-ISS instrument using ground-based lidars and ozonesondes from Hohenpeißenberg and Lauder as well as O3 data from the ACE-FTS instrument. Average differences in the O3 concentration between SAGE III-ISS and the lidar and sonde observations are < 10 % over much of the lower and middle stratosphere. The ACE comparisons are < 5 % from 20 to 45 km. These results provide confidence in the SAGE III measurements of global stratospheric O3 profiles.
Zoë Y. W. Davis, Udo Frieß, Kevin B. Strawbridge, Monika Aggarwaal, Sabour Baray, Elijah G. Schnitzler, Akshay Lobo, Vitali E. Fioletov, Ihab Abboud, Chris A. McLinden, Jim Whiteway, Megan D. Willis, Alex K. Y. Lee, Jeff Brook, Jason Olfert, Jason O'Brien, Ralf Staebler, Hans D. Osthoff, Cristian Mihele, and Robert McLaren
Atmos. Meas. Tech., 13, 1129–1155,Short summary
Here, we evaluate a ground-based remote sensing method (MAX-DOAS) for measuring total pollutant loading and vertical profiles of pollution in the lower atmosphere by comparing our method to a variety of other measurement methods (lidar, sunphotometer, active DOAS, and aircraft measurements). Measurements were made in the Athabasca Oil Sands Region in Alberta, Canada. The complex dataset provided a rare opportunity to evaluate the performance of MAX-DOAS under varying atmospheric conditions.
Benedetto De Rosa, Paolo Di Girolamo, and Donato Summa
Atmos. Meas. Tech., 13, 405–427,Short summary
Temperature and water vapour profiles measured by the BASIL lidar are compared with profiles from several sensors/models, namely radiosondes, the IASI and AIRS satellite sensors and model reanalyses data (ECMWF & ECMWF-ERA). The comparison effort allows for the performance of all of the sensors and models to be assessed in terms of bias and RMS deviation. BASIL measurement quality is confirmed to be high enough for long-term monitoring of atmospheric composition and thermal structure changes.
Stefan Lossow, Charlotta Högberg, Farahnaz Khosrawi, Gabriele P. Stiller, Ralf Bauer, Kaley A. Walker, Sylvia Kellmann, Andrea Linden, Michael Kiefer, Norbert Glatthor, Thomas von Clarmann, Donal P. Murtagh, Jörg Steinwagner, Thomas Röckmann, and Roland Eichinger
Atmos. Meas. Tech., 13, 287–308,
Iolanda Ialongo, Henrik Virta, Henk Eskes, Jari Hovila, and John Douros
Atmos. Meas. Tech., 13, 205–218,Short summary
New satellite-based nitrogen dioxide (NO2) data from TROPOMI/Sentinel 5P are used to monitor air pollution levels at the urban site of Helsinki, Finland. NO2 is a polluting gas produced by fossil fuel combustion. TROPOMI NO2 data agree with ground-based reference measurements within 10 % and show similar day-to-day and weekly variability. The results confirm that satellite-based observations can bring additional information to traditional in situ measurements for urban air quality monitoring.
Laura M. Judd, Jassim A. Al-Saadi, Scott J. Janz, Matthew G. Kowalewski, R. Bradley Pierce, James J. Szykman, Lukas C. Valin, Robert Swap, Alexander Cede, Moritz Mueller, Martin Tiefengraber, Nader Abuhassan, and David Williams
Atmos. Meas. Tech., 12, 6091–6111,Short summary
In 2017, an airborne mapping spectrometer (GeoTASO) was used to observe high-resolution column densities of nitrogen dioxide (NO2) over the western shore of Lake Michigan and the Los Angeles Basin. These data were used to simulate the spatial resolution of current and future satellite NO2 retrievals to evaluate the impact of pixel size on comparisons to ground-based observations in urban areas. As spatial resolution improves, the sensitivity to more heterogeneously polluted scenes increases.
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,Short summary
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.
Jay Herman, Nader Abuhassan, Jhoon Kim, Jae Kim, Manvendra Dubey, Marcelo Raponi, and Maria Tzortziou
Atmos. Meas. Tech., 12, 5593–5612,Short summary
Total column NO2 (TCNO2) from the Ozone Measuring Instrument (OMI) is compared for 14 sites with ground-based PANDORA spectrometer instruments making direct-sun measurements. These sites have high TCNO2, causing significant air quality problems that can affect human health. OMI almost always underestimates the amount of TCNO2 by 50 to 100 %. OMI's large field of view (FOV) is the most likely factor when comparing OMI TCNO2 to retrievals with PANDORA. OMI misses higher afternoon values of TCNO2.
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,Short summary
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.
Katerina Garane, Maria-Elissavet Koukouli, Tijl Verhoelst, Christophe Lerot, Klaus-Peter Heue, Vitali Fioletov, Dimitrios Balis, Alkiviadis Bais, Ariane Bazureau, Angelika Dehn, Florence Goutail, Jose Granville, Debora Griffin, Daan Hubert, Arno Keppens, Jean-Christopher Lambert, Diego Loyola, Chris McLinden, Andrea Pazmino, Jean-Pierre Pommereau, Alberto Redondas, Fabian Romahn, Pieter Valks, Michel Van Roozendael, Jian Xu, Claus Zehner, Christos Zerefos, and Walter Zimmer
Atmos. Meas. Tech., 12, 5263–5287,Short summary
The Sentinel-5 Precursor TROPOMI near real time (NRTI) and offline (OFFL) total ozone column (TOC) products are validated against direct-sun and twilight zenith-sky ground-based TOC measurements and other already known spaceborne sensors. The results show that the TROPOMI TOC measurements are in very good agreement with the ground-based measurements and satellite sensor measurements and that they are well within the product requirements.
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,Short summary
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 %.
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