Articles | Volume 15, issue 19
https://doi.org/10.5194/amt-15-5667-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-15-5667-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
11 Oct 2022
Research article |
| 11 Oct 2022
| 11 Oct 2022
Sensitivity of aerosol optical depth trends using long-term measurements of different sun photometers
Angelos Karanikolas
CORRESPONDING AUTHOR
World Radiation Center, Physikalisch-Meteorologisches Observatorium Davos (PMOD/WRC), Dorfstrasse 33, 7260 Davos, Switzerland
Physics department, ETH Zurich, Franscini-Platz 5, 8093 Zurich, Switzerland
Natalia Kouremeti
World Radiation Center, Physikalisch-Meteorologisches Observatorium Davos (PMOD/WRC), Dorfstrasse 33, 7260 Davos, Switzerland
Julian Gröbner
World Radiation Center, Physikalisch-Meteorologisches Observatorium Davos (PMOD/WRC), Dorfstrasse 33, 7260 Davos, Switzerland
Luca Egli
World Radiation Center, Physikalisch-Meteorologisches Observatorium Davos (PMOD/WRC), Dorfstrasse 33, 7260 Davos, Switzerland
Stelios Kazadzis
World Radiation Center, Physikalisch-Meteorologisches Observatorium Davos (PMOD/WRC), Dorfstrasse 33, 7260 Davos, Switzerland
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Several techniques retrieve of the aerosol size distribution. The Generalized Retrieval of Atmosphere and Surface Properties algorithm can retrieve aerosol size distribution parameters using only aerosol optical depth (AOD) as input that is continuously observed by sun photometers worldwide. In this study, we apply the algorithm to AOD measured by sun photometers and spectroradiometers to assess the performance and limitations of such retrievals and investigate the effect of the spectral range.
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Óscar Alvárez, África Barreto, Omaira E. García, Frank Hase, Rosa D. García, Julian Gröbner, Sergio F. León-Luis, Eliezer Sepúlveda, Virgilio Carreño, Antonio Alcántara, Ramón Ramos, A. Fernando Almansa, Stelios Kazadzis, Noémie Taquet, Carlos Toledano, and Emilio Cuevas
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In this work, we have extended the capabilities of a portable Fourier transform infrared (FTIR) instrument, which was originally designed to provide high-quality greenhouse gas monitoring within COCCON (COllaborative Carbon Column Observing Network). The extension allows the spectrometer to now also provide coincidentally column-integrated aerosol information. This addition of a reference instrument to a global network will be utilised to enhance our understanding of atmospheric chemistry.
Verena Schenzinger, Axel Kreuter, Barbara Klotz, Michael Schwarzmann, and Julian Gröbner
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2023-188, https://doi.org/10.5194/amt-2023-188, 2023
Revised manuscript not accepted
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We present a fast an easy method to incorporate clouds from satellite imagery into a model for calculating surface UV index maps in near-real time. To judge the quality of the model, we compare our results to measurements from ground based detectors. We discuss in detail where variations in either of the values come from and why satellite and ground values might not necessarily be comparable in every situation.
Julian Gröbner, Natalia Kouremeti, Gregor Hülsen, Ralf Zuber, Mario Ribnitzky, Saulius Nevas, Peter Sperfeld, Kerstin Schwind, Philipp Schneider, Stelios Kazadzis, África Barreto, Tom Gardiner, Kavitha Mottungan, David Medland, and Marc Coleman
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Akriti Masoom, Ilias Fountoulakis, Stelios Kazadzis, Ioannis-Panagiotis Raptis, Anna Kampouri, Basil E. Psiloglou, Dimitra Kouklaki, Kyriakoula Papachristopoulou, Eleni Marinou, Stavros Solomos, Anna Gialitaki, Dimitra Founda, Vasileios Salamalikis, Dimitris Kaskaoutis, Natalia Kouremeti, Nikolaos Mihalopoulos, Vassilis Amiridis, Andreas Kazantzidis, Alexandros Papayannis, Christos S. Zerefos, and Kostas Eleftheratos
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Theano Drosoglou, Ioannis-Panagiotis Raptis, Massimo Valeri, Stefano Casadio, Francesca Barnaba, Marcos Herreras-Giralda, Anton Lopatin, Oleg Dubovik, Gabriele Brizzi, Fabrizio Niro, Monica Campanelli, and Stelios Kazadzis
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Xiaoyi Zhao, Vitali Fioletov, Alberto Redondas, Julian Gröbner, Luca Egli, Franz Zeilinger, Javier López-Solano, Alberto Berjón Arroyo, James Kerr, Eliane Maillard Barras, Herman Smit, Michael Brohart, Reno Sit, Akira Ogyu, Ihab Abboud, and Sum Chi Lee
Atmos. Meas. Tech., 16, 2273–2295, https://doi.org/10.5194/amt-16-2273-2023, https://doi.org/10.5194/amt-16-2273-2023, 2023
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The Brewer ozone spectrophotometer is one of the World Meteorological Organization (WMO) Global Atmosphere Watch (GAW)'s standard ozone monitoring instruments since the 1980s. This work is aimed at obtaining answers to (1) why Brewer primary calibration work can only be performed at certain sites (e.g., Izaña and MLO) and (2) what is needed to assure the equivalence of calibration quality from different sites.
Bruce W. Forgan, Julian Gröbner, and Ibrahim Reda
Atmos. Meas. Tech., 16, 727–743, https://doi.org/10.5194/amt-16-727-2023, https://doi.org/10.5194/amt-16-727-2023, 2023
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This paper investigates the Absolute Cavity Pyrgeometer (ACP) and its use in measuring atmospheric terrestrial irradiances traceable to the standard system of units (SI). This work fits into the objective of the Expert Team on Radiation References, established by the World Meteorological Organization (WMO), to develop and validate instrumentation that can be used as reference instruments for terrestrial radiation measurements.
Kyriakoula Papachristopoulou, Ioannis-Panagiotis Raptis, Antonis Gkikas, Ilias Fountoulakis, Akriti Masoom, and Stelios Kazadzis
Atmos. Chem. Phys., 22, 15703–15727, https://doi.org/10.5194/acp-22-15703-2022, https://doi.org/10.5194/acp-22-15703-2022, 2022
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Megacities' air quality is determined by atmospheric aerosols. We focus on changes over the last two decades in the 81 largest cities, using satellite data. European and American cities have lower aerosol compared to African and Asian cities. For European, North American and East Asian cities, aerosols are decreasing over time, especially in China and the US. In the remaining cities, aerosol loads are increasing, particularly in India.
Luca Egli, Julian Gröbner, Gregor Hülsen, Herbert Schill, and René Stübi
Atmos. Meas. Tech., 15, 1917–1930, https://doi.org/10.5194/amt-15-1917-2022, https://doi.org/10.5194/amt-15-1917-2022, 2022
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This study presents traceable total column ozone retrievals from direct solar spectral irradiance measurements. The retrieved ozone does not require any field calibration with a reference instrument as it is required for other operational network instruments such as Brewer or Dobson. Total column ozone can be retrieved with a traceable overall standard uncertainty of less than 0.8 % indicating a benchmark uncertainty for total column ozone measurements.
Antonis Gkikas, Emmanouil Proestakis, Vassilis Amiridis, Stelios Kazadzis, Enza Di Tomaso, Eleni Marinou, Nikos Hatzianastassiou, Jasper F. Kok, and Carlos Pérez García-Pando
Atmos. Chem. Phys., 22, 3553–3578, https://doi.org/10.5194/acp-22-3553-2022, https://doi.org/10.5194/acp-22-3553-2022, 2022
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We present a comprehensive climatological analysis of dust optical depth (DOD) relying on the MIDAS dataset. MIDAS provides columnar mid-visible (550 nm) DOD at fine spatial resolution (0.1° × 0.1°) over a 15-year period (2003–2017). In the current study, the analysis is performed at various spatial (from regional to global) and temporal (from months to years) scales. More specifically, focus is given to specific regions hosting the major dust sources as well as downwind areas of the planet.
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.
Stavros-Andreas Logothetis, Vasileios Salamalikis, Antonis Gkikas, Stelios Kazadzis, Vassilis Amiridis, and Andreas Kazantzidis
Atmos. Chem. Phys., 21, 16499–16529, https://doi.org/10.5194/acp-21-16499-2021, https://doi.org/10.5194/acp-21-16499-2021, 2021
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This study investigates the temporal trends of dust optical depth (DOD; 550 nm) on global, regional and seasonal scales over a 15-year period (2003–2017) using the MIDAS (ModIs Dust AeroSol) dataset. The findings of this study revealed that the DOD was increased across the central Sahara and the Arabian Peninsula, with opposite trends over the eastern and western Sahara, the Thar and Gobi deserts, in the Bodélé Depression, and in the southern Mediterranean.
Xinyuan Hou, Martin Wild, Doris Folini, Stelios Kazadzis, and Jan Wohland
Earth Syst. Dynam., 12, 1099–1113, https://doi.org/10.5194/esd-12-1099-2021, https://doi.org/10.5194/esd-12-1099-2021, 2021
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Solar photovoltaics (PV) matters for the carbon neutrality goal. We use climate scenarios to quantify climate risk for PV in Europe and find higher PV potential. The seasonal cycle of PV generation changes in most places. We find an increase in the spatial correlations of daily PV production, implying that PV power balancing through redistribution will be more difficult in the future. Thus, changes in the spatiotemporal structure of PV generation should be included in power system design.
Panagiotis G. Kosmopoulos, Stelios Kazadzis, Alois W. Schmalwieser, Panagiotis I. Raptis, Kyriakoula Papachristopoulou, Ilias Fountoulakis, Akriti Masoom, Alkiviadis F. Bais, Julia Bilbao, Mario Blumthaler, Axel Kreuter, Anna Maria Siani, Kostas Eleftheratos, Chrysanthi Topaloglou, Julian Gröbner, Bjørn Johnsen, Tove M. Svendby, Jose Manuel Vilaplana, Lionel Doppler, Ann R. Webb, Marina Khazova, Hugo De Backer, Anu Heikkilä, Kaisa Lakkala, Janusz Jaroslawski, Charikleia Meleti, Henri Diémoz, Gregor Hülsen, Barbara Klotz, John Rimmer, and Charalampos Kontoes
Atmos. Meas. Tech., 14, 5657–5699, https://doi.org/10.5194/amt-14-5657-2021, https://doi.org/10.5194/amt-14-5657-2021, 2021
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Large-scale retrievals of the ultraviolet index (UVI) in real time by exploiting the modern Earth observation data and techniques are capable of forming operational early warning systems that raise awareness among citizens of the health implications of high UVI doses. In this direction a novel UVI operating system, the so-called UVIOS, was introduced for massive outputs, while its performance was tested against ground-based measurements revealing a dependence on the input quality and resolution.
Antti Arola, William Wandji Nyamsi, Antti Lipponen, Stelios Kazadzis, Nickolay A. Krotkov, and Johanna Tamminen
Atmos. Meas. Tech., 14, 4947–4957, https://doi.org/10.5194/amt-14-4947-2021, https://doi.org/10.5194/amt-14-4947-2021, 2021
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Methods to estimate surface UV radiation from satellite measurements offer the only means to obtain global coverage, and the development of satellite-based UV algorithms has been ongoing since the early 1990s. One of the main challenges in this development has been how to account for the overall effect of absorption by atmospheric aerosols. One such method was suggested roughly a decade ago, and in this study we propose further improvements for this kind of approach.
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.
Marek Šmíd, Geiland Porrovecchio, Jiří Tesař, Tim Burnitt, Luca Egli, Julian Grőbner, Petr Linduška, and Martin Staněk
Atmos. Meas. Tech., 14, 3573–3582, https://doi.org/10.5194/amt-14-3573-2021, https://doi.org/10.5194/amt-14-3573-2021, 2021
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We designed and developed a tuneable and portable radiation source (TuPS) to provide a reference wavelength scale, with a bandwidth of emitted radiation of 0.13 nm and uncertainty in wavelength of 0.02 nm. TuPS was successfully used for the in-field characterization of 14 Dobson spectrophotometers in campaigns in Europe. The line spread functions of Dobsons measured by TuPS in conjunction with the cross-sections from IUP improves the consistency between the Dobson and Brewer from 3 % to 1 %.
Julian Gröbner, Herbert Schill, Luca Egli, and René Stübi
Atmos. Meas. Tech., 14, 3319–3331, https://doi.org/10.5194/amt-14-3319-2021, https://doi.org/10.5194/amt-14-3319-2021, 2021
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The world's longest continuous total column ozone time series was initiated in 1926 at the Lichtklimatisches Observatorium (LKO), at Arosa, in the Swiss Alps. The measurements between Dobson and Brewer spectroradiometers have shown seasonal variations of the order of 2 %. The results of the study show that the consistency between the two instrument types can be significantly improved when the ozone cross-sections from Serdyuchenko et al. (2013) and the measured slit functions are used.
Myrto Gratsea, Tim Bösch, Panagiotis Kokkalis, Andreas Richter, Mihalis Vrekoussis, Stelios Kazadzis, Alexandra Tsekeri, Alexandros Papayannis, Maria Mylonaki, Vassilis Amiridis, Nikos Mihalopoulos, and Evangelos Gerasopoulos
Atmos. Meas. Tech., 14, 749–767, https://doi.org/10.5194/amt-14-749-2021, https://doi.org/10.5194/amt-14-749-2021, 2021
Antonis Gkikas, Emmanouil Proestakis, Vassilis Amiridis, Stelios Kazadzis, Enza Di Tomaso, Alexandra Tsekeri, Eleni Marinou, Nikos Hatzianastassiou, and Carlos Pérez García-Pando
Atmos. Meas. Tech., 14, 309–334, https://doi.org/10.5194/amt-14-309-2021, https://doi.org/10.5194/amt-14-309-2021, 2021
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We present the development of the MIDAS (ModIs Dust AeroSol) data set, providing daily dust optical depth (DOD; 550 nm) at a global scale and fine spatial resolution (0.1° x 0.1°) over a 15-year period (2003–2017). It has been developed via the synergy of MODIS-Aqua and MERRA-2 data, while CALIOP and AERONET retrievals are used for its assessment. MIDAS upgrades existing dust observational capabilities, and it is suitable for dust climatological studies, model evaluation, and data assimilation.
Kaisa Lakkala, Jukka Kujanpää, Colette Brogniez, Nicolas Henriot, Antti Arola, Margit Aun, Frédérique Auriol, Alkiviadis F. Bais, Germar Bernhard, Veerle De Bock, Maxime Catalfamo, Christine Deroo, Henri Diémoz, Luca Egli, Jean-Baptiste Forestier, Ilias Fountoulakis, Katerina Garane, Rosa Delia Garcia, Julian Gröbner, Seppo Hassinen, Anu Heikkilä, Stuart Henderson, Gregor Hülsen, Bjørn Johnsen, Niilo Kalakoski, Angelos Karanikolas, Tomi Karppinen, Kevin Lamy, Sergio F. León-Luis, Anders V. Lindfors, Jean-Marc Metzger, Fanny Minvielle, Harel B. Muskatel, Thierry Portafaix, Alberto Redondas, Ricardo Sanchez, Anna Maria Siani, Tove Svendby, and Johanna Tamminen
Atmos. Meas. Tech., 13, 6999–7024, https://doi.org/10.5194/amt-13-6999-2020, https://doi.org/10.5194/amt-13-6999-2020, 2020
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The TROPOspheric Monitoring Instrument (TROPOMI) onboard the Sentinel-5 Precursor (S5P) satellite was launched on 13 October 2017 to provide the atmospheric composition for atmosphere and climate research. Ground-based data from 25 sites located in Arctic, subarctic, temperate, equatorial and Antarctic
areas were used for the validation of the TROPOMI surface ultraviolet (UV) radiation product. For most sites 60 %–80 % of TROPOMI data was within ± 20 % of ground-based data.
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, https://doi.org/10.5194/amt-13-6141-2020, https://doi.org/10.5194/amt-13-6141-2020, 2020
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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.
Ilias Fountoulakis, Henri Diémoz, Anna Maria Siani, Gregor Hülsen, and Julian Gröbner
Earth Syst. Sci. Data, 12, 2787–2810, https://doi.org/10.5194/essd-12-2787-2020, https://doi.org/10.5194/essd-12-2787-2020, 2020
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In this study we discuss the procedures and the technical aspects which ensure the high quality of the measurements of the global solar ultraviolet (UV) irradiance performed by a Bentham spectroradiometer located at Aosta–Saint-Christophe (north-western Alps), Italy. This particular instrument is the reference for the Aosta Valley UV monitoring network, which is the first UV monitoring network in Italy. The final spectra constitute one of the most accurate datasets globally.
Teruyuki Nakajima, Monica Campanelli, Huizheng Che, Victor Estellés, Hitoshi Irie, Sang-Woo Kim, Jhoon Kim, Dong Liu, Tomoaki Nishizawa, Govindan Pandithurai, Vijay Kumar Soni, Boossarasiri Thana, Nas-Urt Tugjsurn, Kazuma Aoki, Sujung Go, Makiko Hashimoto, Akiko Higurashi, Stelios Kazadzis, Pradeep Khatri, Natalia Kouremeti, Rei Kudo, Franco Marenco, Masahiro Momoi, Shantikumar S. Ningombam, Claire L. Ryder, Akihiro Uchiyama, and Akihiro Yamazaki
Atmos. Meas. Tech., 13, 4195–4218, https://doi.org/10.5194/amt-13-4195-2020, https://doi.org/10.5194/amt-13-4195-2020, 2020
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This paper overviews the progress in sky radiometer technology and the development of the network called SKYNET. It is found that the technology has produced useful on-site calibration methods, retrieval algorithms, and data analyses from sky radiometer observations of aerosol, cloud, water vapor, and ozone. The paper also discusses current issues of SKYNET to provide better information for the community.
Christine Aebi, Julian Gröbner, Stelios Kazadzis, Laurent Vuilleumier, Antonis Gkikas, and Niklaus Kämpfer
Atmos. Meas. Tech., 13, 907–923, https://doi.org/10.5194/amt-13-907-2020, https://doi.org/10.5194/amt-13-907-2020, 2020
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Clouds are one of the largest sources of uncertainties in climate models. The current study estimates the cloud optical thickness (COT), the effective droplet radius and the single scattering albedo of stratus–altostratus and cirrus–cirrostratus clouds in Payerne, Switzerland, by combining ground- and satellite-based measurements and radiative transfer models. The estimated values are thereafter compared with data retrieved from other methods. The mean COT is distinct for different seasons.
Stephan Nyeki, Stefan Wacker, Christine Aebi, Julian Gröbner, Giovanni Martucci, and Laurent Vuilleumier
Atmos. Chem. Phys., 19, 13227–13241, https://doi.org/10.5194/acp-19-13227-2019, https://doi.org/10.5194/acp-19-13227-2019, 2019
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The trends of meteorological parameters and surface downward shortwave radiation (DSR) and downward longwave radiation (DLR) were analysed at four stations (between 370 and 3580 m a. s. l.) in Switzerland for the 1996–2015 period. Trends in DSR and DLR were positive during cloudy as well as clear conditions. The trend due to the influence of clouds decreased in magnitude, which implies a reduction in cloud cover and/or a change towards a different cloud type over the four Swiss sites.
Emilio Cuevas, Pedro Miguel Romero-Campos, Natalia Kouremeti, Stelios Kazadzis, Petri Räisänen, Rosa Delia García, Africa Barreto, Carmen Guirado-Fuentes, Ramón Ramos, Carlos Toledano, Fernando Almansa, and Julian Gröbner
Atmos. Meas. Tech., 12, 4309–4337, https://doi.org/10.5194/amt-12-4309-2019, https://doi.org/10.5194/amt-12-4309-2019, 2019
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A comprehensive comparison of more than 70 000 synchronous 1 min aerosol optical depth (AOD) data from 3 Global Atmosphere Watch precision filter radiometers (GAW-PFR) and 15 Aerosol Robotic Network Cimel radiometers (AERONET-Cimel) was performed for the four
nearwavelengths (380, 440, 500 and 870 nm) in the period 2005–2015. The goal of this study is to assess whether their long term AOD data are comparable and consistent.
Christine Aebi, Julian Gröbner, and Niklaus Kämpfer
Atmos. Meas. Tech., 11, 5549–5563, https://doi.org/10.5194/amt-11-5549-2018, https://doi.org/10.5194/amt-11-5549-2018, 2018
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A newly developed hemispherical thermal infrared cloud camera (IRCCAM) is presented. The IRCCAM allows automatic cloud detection during the day and at night-time. The cloud fraction determined from the IRCCAM is compared with the cloud fraction determined from other instruments over a time period of 2 years. The IRCCAM has an agreement of +/- 2 oktas cloud fraction in 90 % of the data compared to other instruments. There are no significant differences between seasons or different times of day.
Carlos Toledano, Ramiro González, David Fuertes, Emilio Cuevas, Thomas F. Eck, Stelios Kazadzis, Natalia Kouremeti, Julian Gröbner, Philippe Goloub, Luc Blarel, Roberto Román, África Barreto, Alberto Berjón, Brent N. Holben, and Victoria E. Cachorro
Atmos. Chem. Phys., 18, 14555–14567, https://doi.org/10.5194/acp-18-14555-2018, https://doi.org/10.5194/acp-18-14555-2018, 2018
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Most of the ground-based radiometric networks have their reference instruments and/or calibrate them at Mauna Loa or Izaña. The suitability of these high-mountain stations for absolute radiometric calibrations is investigated with the support of 20 years of first-class Sun photometer data from the AERONET and GAW-PFR networks. We analyze the number of calibration days at each site in a climatological sense and investigate the uncertainty of the calibrations based on long-term statistics.
Marco Zanatta, Paolo Laj, Martin Gysel, Urs Baltensperger, Stergios Vratolis, Konstantinos Eleftheriadis, Yutaka Kondo, Philippe Dubuisson, Victor Winiarek, Stelios Kazadzis, Peter Tunved, and Hans-Werner Jacobi
Atmos. Chem. Phys., 18, 14037–14057, https://doi.org/10.5194/acp-18-14037-2018, https://doi.org/10.5194/acp-18-14037-2018, 2018
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The research community aims to quantify the actual contribution of soot particles to the recent Arctic warming. We discovered that mixing of soot with other components might enhance its light absorption power by 50 %. The neglection of such amplification might lead to the underestimation of radiative forcing by 0.12 W m−2. Thus a better understanding of the optical properties of soot is a crucial step for an accurate quantification of the radiative impact of soot in the Arctic atmosphere.
Kaisa Lakkala, Antti Arola, Julian Gröbner, Sergio Fabian León-Luis, Alberto Redondas, Stelios Kazadzis, Tomi Karppinen, Juha Matti Karhu, Luca Egli, Anu Heikkilä, Tapani Koskela, Antonio Serrano, and José Manuel Vilaplana
Atmos. Meas. Tech., 11, 5167–5180, https://doi.org/10.5194/amt-11-5167-2018, https://doi.org/10.5194/amt-11-5167-2018, 2018
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The performance of the cosine error correction method for correcting spectral UV measurements of the Brewer spectroradiometer was studied. The correction depends on the sky radiation distribution, which can change during one spectral scan. The results showed that the correction varied between 4 and 14 %, and that the relative differences between the reference and the Brewer diminished by 10 %. The method is applicable to other instruments as long as the required input parameters are available.
Angela Benedetti, Jeffrey S. Reid, Peter Knippertz, John H. Marsham, Francesca Di Giuseppe, Samuel Rémy, Sara Basart, Olivier Boucher, Ian M. Brooks, Laurent Menut, Lucia Mona, Paolo Laj, Gelsomina Pappalardo, Alfred Wiedensohler, Alexander Baklanov, Malcolm Brooks, Peter R. Colarco, Emilio Cuevas, Arlindo da Silva, Jeronimo Escribano, Johannes Flemming, Nicolas Huneeus, Oriol Jorba, Stelios Kazadzis, Stefan Kinne, Thomas Popp, Patricia K. Quinn, Thomas T. Sekiyama, Taichu Tanaka, and Enric Terradellas
Atmos. Chem. Phys., 18, 10615–10643, https://doi.org/10.5194/acp-18-10615-2018, https://doi.org/10.5194/acp-18-10615-2018, 2018
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Numerical prediction of aerosol particle properties has become an important activity at many research and operational weather centers. This development is due to growing interest from a diverse set of stakeholders, such as air quality regulatory bodies, aviation authorities, solar energy plant managers, climate service providers, and health professionals. This paper describes the advances in the field and sets out requirements for observations for the sustainability of these activities.
Alberto Redondas, Virgilio Carreño, Sergio F. León-Luis, Bentorey Hernández-Cruz, Javier López-Solano, Juan J. Rodriguez-Franco, José M. Vilaplana, Julian Gröbner, John Rimmer, Alkiviadis F. Bais, Vladimir Savastiouk, Juan R. Moreta, Lamine Boulkelia, Nis Jepsen, Keith M. Wilson, Vadim Shirotov, and Tomi Karppinen
Atmos. Chem. Phys., 18, 9441–9455, https://doi.org/10.5194/acp-18-9441-2018, https://doi.org/10.5194/acp-18-9441-2018, 2018
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This work shows an overview of the total ozone comparison of the Brewer instrument during the 10th RBCC-E campaign in a joint effort with the EUBREWNET COST 1207 action. The status of the network after 2 years of calibration shows 16 out of the 21 participating Brewer instruments (76 %) agreed within better than ±1 %, and 10 instruments (50 %) agreed within better than ±0.5 %. After applying the final calibration and the stray light correction all working instruments agreed at the ±0.5 % level.
Anna Vaskuri, Petri Kärhä, Luca Egli, Julian Gröbner, and Erkki Ikonen
Atmos. Meas. Tech., 11, 3595–3610, https://doi.org/10.5194/amt-11-3595-2018, https://doi.org/10.5194/amt-11-3595-2018, 2018
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In this work, we introduce a Monte Carlo uncertainty analysis that takes into account possible systematic spectral deviations in the atmospheric full spectrum ozone retrieval method. Accounting for possible systematic spectral deviations in the spectral data is important since they produce larger total ozone column uncertainties than uncorrelated noise-like variations that traditional uncertainty estimations predict.
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 %).
Theano Drosoglou, Maria Elissavet Koukouli, Natalia Kouremeti, Alkiviadis F. Bais, Irene Zyrichidou, Dimitris Balis, Ronald J. van der A, Jin Xu, and Ang Li
Atmos. Meas. Tech., 11, 2239–2255, https://doi.org/10.5194/amt-11-2239-2018, https://doi.org/10.5194/amt-11-2239-2018, 2018
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A diurnal pattern of tropospheric NO2 with two maxima around late morning and late afternoon is revealed, reflecting high anthropogenic emissions, and a minimum at noon, due to photochemical destruction of tropospheric NO2. GOME-2B shows the smallest underestimation despite its large pixel size. The distance between the measurement location and the satellite pixel center affects mostly GOME-2B data selection. The effect of clouds is more profound on the selection of OMI overpass data.
Daniela Meloni, Alcide di Sarra, Gérard Brogniez, Cyrielle Denjean, Lorenzo De Silvestri, Tatiana Di Iorio, Paola Formenti, José L. Gómez-Amo, Julian Gröbner, Natalia Kouremeti, Giuliano Liuzzi, Marc Mallet, Giandomenico Pace, and Damiano M. Sferlazzo
Atmos. Chem. Phys., 18, 4377–4401, https://doi.org/10.5194/acp-18-4377-2018, https://doi.org/10.5194/acp-18-4377-2018, 2018
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This study examines how different aerosol optical properties determine the dust longwave radiative effects at the surface, in the atmosphere and at the top of the atmosphere, based on the combination of remote sensing and in situ observations from the ground, from airborne sensors, and from space, by means of radiative transfer modelling. The closure experiment is based on longwave irradiances and spectral brightness temperatures measured during the 2013 ChArMEx–ADRIMED campaign at Lampedusa.
Christof Janssen, Hadj Elandaloussi, and Julian Gröbner
Atmos. Meas. Tech., 11, 1707–1723, https://doi.org/10.5194/amt-11-1707-2018, https://doi.org/10.5194/amt-11-1707-2018, 2018
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Monitoring ozone layer recovery at a rate of few percent per decade requires dedicated instrumentation and spectroscopic data of the highest quality. Highly accurate absorption cross sections of ozone are rare, especially in the important UV region between 300 and 340 nm. Our measurement provides the first reference point with permil level of accuracy in this range. Interestingly, our value is lower than currently used data. This might resolve an inconsistency between UV and IR measurements.
Javier López-Solano, Alberto Redondas, Thomas Carlund, Juan J. Rodriguez-Franco, Henri Diémoz, Sergio F. León-Luis, Bentorey Hernández-Cruz, Carmen Guirado-Fuentes, Natalia Kouremeti, Julian Gröbner, Stelios Kazadzis, Virgilio Carreño, Alberto Berjón, Daniel Santana-Díaz, Manuel Rodríguez-Valido, Veerle De Bock, Juan R. Moreta, John Rimmer, Andrew R. D. Smedley, Lamine Boulkelia, Nis Jepsen, Paul Eriksen, Alkiviadis F. Bais, Vadim Shirotov, José M. Vilaplana, Keith M. Wilson, and Tomi Karppinen
Atmos. Chem. Phys., 18, 3885–3902, https://doi.org/10.5194/acp-18-3885-2018, https://doi.org/10.5194/acp-18-3885-2018, 2018
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The European Brewer Network (EUBREWNET, COST Action ES1207) is comprised of close to 50 instruments and currently provides near-real-time ozone and UV data. Aerosols also play key role in the Earth–atmosphere system and introduce a large uncertainty into our understanding of climate change. In this work we describe and validate a method to incorporate the measurement of aerosols in EUBREWNET. We find that this Brewer network can provide reliable aerosol data across Europe in the UV range.
Stelios Kazadzis, Natalia Kouremeti, Henri Diémoz, Julian Gröbner, Bruce W. Forgan, Monica Campanelli, Victor Estellés, Kathleen Lantz, Joseph Michalsky, Thomas Carlund, Emilio Cuevas, Carlos Toledano, Ralf Becker, Stephan Nyeki, Panagiotis G. Kosmopoulos, Viktar Tatsiankou, Laurent Vuilleumier, Frederick M. Denn, Nozomu Ohkawara, Osamu Ijima, Philippe Goloub, Panagiotis I. Raptis, Michael Milner, Klaus Behrens, Africa Barreto, Giovanni Martucci, Emiel Hall, James Wendell, Bryan E. Fabbri, and Christoph Wehrli
Atmos. Chem. Phys., 18, 3185–3201, https://doi.org/10.5194/acp-18-3185-2018, https://doi.org/10.5194/acp-18-3185-2018, 2018
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Aerosol optical depth measured from ground-based sun photometers is the most important parameter for studying the changes in the Earth's radiation balance due to aerosols. Representatives for various sun photometer types belonging to individual institutions or international aerosol networks gather every 5 years, for 3 weeks, in Davos, Switzerland, in order to compare their aeorosol optical depth retrievals. This work presents the results of the latest (fourth) filter radiometer intercomparison.
Panagiotis-Ioannis Raptis, Stelios Kazadzis, Julian Gröbner, Natalia Kouremeti, Lionel Doppler, Ralf Becker, and Constantinos Helmis
Atmos. Meas. Tech., 11, 1143–1157, https://doi.org/10.5194/amt-11-1143-2018, https://doi.org/10.5194/amt-11-1143-2018, 2018
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The purpose of this work is to retrieve integrated water vapour using spectral measurements from Precision Solar Spectroradiometer (PSR). Two different approaches were developed one using single-channel direct sun irradiance measurements, and the second one integrating at a certain spectral region. The results of the spectral approach are closer to the retrievals of non-photometric techniques (GPS, microwave radiometer and radiosondes), suggesting this method provide more accurate IWV product.
Stelios Kazadzis, Dimitra Founda, Basil E. Psiloglou, Harry Kambezidis, Nickolaos Mihalopoulos, Arturo Sanchez-Lorenzo, Charikleia Meleti, Panagiotis I. Raptis, Fragiskos Pierros, and Pierre Nabat
Atmos. Chem. Phys., 18, 2395–2411, https://doi.org/10.5194/acp-18-2395-2018, https://doi.org/10.5194/acp-18-2395-2018, 2018
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The National Observatory of Athens has been collecting solar radiation, sunshine duration, and cloud and visibility data/observations since the beginning of the 20th century. In this work we present surface solar radiation data since 1953 and reconstructed data since 1900. We have attempted to show and discuss the long-term changes in solar surface radiation over Athens, Greece, using these unique datasets.
Panagiotis G. Kosmopoulos, Stelios Kazadzis, Michael Taylor, Panagiotis I. Raptis, Iphigenia Keramitsoglou, Chris Kiranoudis, and Alkiviadis F. Bais
Atmos. Meas. Tech., 11, 907–924, https://doi.org/10.5194/amt-11-907-2018, https://doi.org/10.5194/amt-11-907-2018, 2018
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Continuous monitoring of solar energy from space is critical for its efficient exploitation and distribution. For this reason we developed neural-network- and function-based real-time models, which are capable of producing massive radiation outputs in high spectral, spatial and temporal resolution. The models' performance against ground-based measurements revealed a dependence on input quality and resolution, and an overall accuracy under cloudless and high solar energy potential conditions.
Stelios Kazadzis, Natalia Kouremeti, Stephan Nyeki, Julian Gröbner, and Christoph Wehrli
Geosci. Instrum. Method. Data Syst., 7, 39–53, https://doi.org/10.5194/gi-7-39-2018, https://doi.org/10.5194/gi-7-39-2018, 2018
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The World Optical Depth Research Calibration Center (WORCC) has been established after the recommendations of WMO for calibration of aerosol optical depth (AOD) -related sun photometers. WORCC is mandated to initiate homogenization activities among different AOD networks and to run a network (GAW-PFR) of sun photometers. To calibrate such instruments aiming at low measurement uncertainties the quality assurance, quality control and a basic hierarchy have to be defined and followed.
Emmanouil Proestakis, Vassilis Amiridis, Eleni Marinou, Aristeidis K. Georgoulias, Stavros Solomos, Stelios Kazadzis, Julien Chimot, Huizheng Che, Georgia Alexandri, Ioannis Binietoglou, Vasiliki Daskalopoulou, Konstantinos A. Kourtidis, Gerrit de Leeuw, and Ronald J. van der A
Atmos. Chem. Phys., 18, 1337–1362, https://doi.org/10.5194/acp-18-1337-2018, https://doi.org/10.5194/acp-18-1337-2018, 2018
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We provide a 3-D climatology of desert dust aerosols over South and East Asia, based on 9 years of CALIPSO observations and an EARLINET methodology. The results provide the horizontal, vertical and seasonal distribution of dust aerosols over SE Asia along with the change in dust transport pathways. The dataset is unique for its potential applications, including evaluation and assimilation activities in atmospheric simulations and the estimation of the climatic impact of dust aerosols.
Christine Aebi, Julian Gröbner, Niklaus Kämpfer, and Laurent Vuilleumier
Atmos. Meas. Tech., 10, 4587–4600, https://doi.org/10.5194/amt-10-4587-2017, https://doi.org/10.5194/amt-10-4587-2017, 2017
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The current study analyses the cloud radiative effect during the daytime depending on cloud fraction and cloud type at two stations in Switzerland over a time period of 3–5 years. Information about fractional cloud coverage and cloud type is retrieved from images taken by visible all-sky cameras. Cloud cover, cloud type and other atmospheric parameters have an influence on the magnitude of the longwave cloud effect as well as on the shortwave.
René Stübi, Herbert Schill, Jörg Klausen, Laurent Vuilleumier, Julian Gröbner, Luca Egli, and Dominique Ruffieux
Atmos. Meas. Tech., 10, 4479–4490, https://doi.org/10.5194/amt-10-4479-2017, https://doi.org/10.5194/amt-10-4479-2017, 2017
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Long-term measurement series are the pillars of all climate change analysis. The Arosa total ozone series is the world's longest record, starting in 1926. To secure the future of these measurements, it is foreseen to move the instruments in Davos. To ascertain that the series will not be affected by this change, a multiyear campaign of parallel measurements on both sites has been done. The analysis of these data is presented and it is concluded that no discernible difference can be identified.
Julian Gröbner, Ingo Kröger, Luca Egli, Gregor Hülsen, Stefan Riechelmann, and Peter Sperfeld
Atmos. Meas. Tech., 10, 3375–3383, https://doi.org/10.5194/amt-10-3375-2017, https://doi.org/10.5194/amt-10-3375-2017, 2017
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We have produced a benchmark high-resolution solar extraterrestrial spectrum from ground-based measurements of direct solar irradiance in the wavelength range 300 to 500 nm. This spectrum can be used for model calculations and for validating solar spectra measured in space. The metrological traceability of this solar spectrum to the International System of Units (SI) is assured by an unbroken chain of calibrations traceable to the primary spectral irradiance standard of PTB.
Stephan Nyeki, Stefan Wacker, Julian Gröbner, Wolfgang Finsterle, and Martin Wild
Atmos. Meas. Tech., 10, 3057–3071, https://doi.org/10.5194/amt-10-3057-2017, https://doi.org/10.5194/amt-10-3057-2017, 2017
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A large number of radiometers used to measure solar and terrestrial broadband radiation are traceable to World Standard Groups at PMOD/WRC in Davos, Switzerland. A small correction of each group may be required in the future, and this study examines the methods and implications of this on data sets collected at four remote baseline stations since the 1990s. The goal is to develop a better estimate of the solar and terrestrial radiation budget at the Earth's surface.
Panagiotis G. Kosmopoulos, Stelios Kazadzis, Michael Taylor, Eleni Athanasopoulou, Orestis Speyer, Panagiotis I. Raptis, Eleni Marinou, Emmanouil Proestakis, Stavros Solomos, Evangelos Gerasopoulos, Vassilis Amiridis, Alkiviadis Bais, and Charalabos Kontoes
Atmos. Meas. Tech., 10, 2435–2453, https://doi.org/10.5194/amt-10-2435-2017, https://doi.org/10.5194/amt-10-2435-2017, 2017
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We study the impact of dust on solar energy using remote sensing data in conjunction with synergistic modelling and forecasting techniques. Under high aerosol loads, we found great solar energy losses of the order of 80 and 50% for concentrated solar power and photovoltaic installations, respectively. The 1-day forecast presented an overall accuracy within 10% in direct comparison to the real conditions under high energy potential, optimising the efficient energy planning and policies.
Theano Drosoglou, Alkiviadis F. Bais, Irene Zyrichidou, Natalia Kouremeti, Anastasia Poupkou, Natalia Liora, Christos Giannaros, Maria Elissavet Koukouli, Dimitris Balis, and Dimitrios Melas
Atmos. Chem. Phys., 17, 5829–5849, https://doi.org/10.5194/acp-17-5829-2017, https://doi.org/10.5194/acp-17-5829-2017, 2017
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We present ground-based tropospheric NO2 measurements performed within the area of Thessaloniki, Greece. The comparisons with OMI/Aura, GOME-2A and GOME-2B data sets have shown a significant underestimation of the NO2 levels over the urban area by the satellite sensors. This finding can be attributed to the strong NO2 gradients. By applying adjustment factors, calculated using an air quality model, on the OMI/Aura observations, the comparison over the urban site has improved significantly.
Thomas Carlund, Natalia Kouremeti, Stelios Kazadzis, and Julian Gröbner
Atmos. Meas. Tech., 10, 905–923, https://doi.org/10.5194/amt-10-905-2017, https://doi.org/10.5194/amt-10-905-2017, 2017
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Aerosols play an important role in atmospheric processes. Aerosol optical depth is the most common measure of columnar aerosol load. We present a sunphotometer called UVPFR that is able to measure aerosol optical depth in the ultraviolet range, including the calibration, characterization and validation of the instrument/measurements. The instrument will serve as a reference on the intercalibration of Brewer spectrophotometers that are also able to measure aerosol optical depth in the UV region.
Christos S. Zerefos, Kostas Eleftheratos, John Kapsomenakis, Stavros Solomos, Antje Inness, Dimitris Balis, Alberto Redondas, Henk Eskes, Marc Allaart, Vassilis Amiridis, Arne Dahlback, Veerle De Bock, Henri Diémoz, Ronny Engelmann, Paul Eriksen, Vitali Fioletov, Julian Gröbner, Anu Heikkilä, Irina Petropavlovskikh, Janusz Jarosławski, Weine Josefsson, Tomi Karppinen, Ulf Köhler, Charoula Meleti, Christos Repapis, John Rimmer, Vladimir Savinykh, Vadim Shirotov, Anna Maria Siani, Andrew R. D. Smedley, Martin Stanek, and René Stübi
Atmos. Chem. Phys., 17, 551–574, https://doi.org/10.5194/acp-17-551-2017, https://doi.org/10.5194/acp-17-551-2017, 2017
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The paper makes a convincing case that the Brewer network is capable of detecting enhanced SO2 columns, as observed, e.g., after volcanic eruptions. For this reason, large volcanic eruptions of the past decade have been used to detect and forecast SO2 plumes of volcanic origin using the Brewer and other ground-based networks, aided by satellite, trajectory analysis calculations and modelling.
Stelios Kazadzis, Panagiotis Raptis, Natalia Kouremeti, Vassilis Amiridis, Antti Arola, Evangelos Gerasopoulos, and Gregory L. Schuster
Atmos. Meas. Tech., 9, 5997–6011, https://doi.org/10.5194/amt-9-5997-2016, https://doi.org/10.5194/amt-9-5997-2016, 2016
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Aerosols play an important role in the Earth's climate. One of the main aerosol properties is the single scattering albedo which is a measure of the aerosol absorption. In this work we have presented a method to retrieve this aerosol property in the ultraviolet and we presented the results for measurements at the urban environment of Athens, Greece. We show that the spectral dependence of the aerosol absorption in the VIS–IR and the UV range depends on the aerosol composition and type.
Dimitra Founda, Stelios Kazadzis, Nikolaos Mihalopoulos, Evangelos Gerasopoulos, Maria Lianou, and Panagiotis I. Raptis
Atmos. Chem. Phys., 16, 11219–11236, https://doi.org/10.5194/acp-16-11219-2016, https://doi.org/10.5194/acp-16-11219-2016, 2016
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Historical time series are unique sources of information for past climate and atmospheric composition change. The 82-year time series of visibility data collected at the National Observatory of Athens (NOA) was an excellent proxy for the long-term evolution of particulate pollution in the eastern Mediterranean, at times when direct aerosol measurements were missing. Evolution of particulate pollution of both local and regional origin is nicely reflected on visibility records of NOA.
Antonis Gkikas, Sara Basart, Nikos Hatzianastassiou, Eleni Marinou, Vassilis Amiridis, Stelios Kazadzis, Jorge Pey, Xavier Querol, Oriol Jorba, Santiago Gassó, and José Maria Baldasano
Atmos. Chem. Phys., 16, 8609–8642, https://doi.org/10.5194/acp-16-8609-2016, https://doi.org/10.5194/acp-16-8609-2016, 2016
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This study presents the 3-D structures of intense Mediterranean desert dust outbreaks, over the period Mar 2000–Feb 2013. The desert dust (DD) episodes are identified through an objective and dynamic algorithm, which utilizes satellite retrievals (MODIS, TOMS and OMI) as inputs. The performance of the satellite algorithm is evaluated vs. AERONET and PM10 data. The geometrical characteristics of the identified DD episodes are analyzed using the collocated CALIOP profiles as a complementary tool.
Jani Huttunen, Harri Kokkola, Tero Mielonen, Mika Esa Juhani Mononen, Antti Lipponen, Juha Reunanen, Anders Vilhelm Lindfors, Santtu Mikkonen, Kari Erkki Juhani Lehtinen, Natalia Kouremeti, Alkiviadis Bais, Harri Niska, and Antti Arola
Atmos. Chem. Phys., 16, 8181–8191, https://doi.org/10.5194/acp-16-8181-2016, https://doi.org/10.5194/acp-16-8181-2016, 2016
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For a good estimate of the current forcing by anthropogenic aerosols, knowledge in past is needed. One option to lengthen time series is to retrieve aerosol optical depth from solar radiation measurements. We have evaluated several methods for this task. Most of the methods produce aerosol optical depth estimates with a good accuracy. However, machine learning methods seem to be the most applicable not to produce any systematic biases, since they do not need constrain the aerosol properties.
Henri Diémoz, Kostas Eleftheratos, Stelios Kazadzis, Vassilis Amiridis, and Christos S. Zerefos
Atmos. Meas. Tech., 9, 1871–1888, https://doi.org/10.5194/amt-9-1871-2016, https://doi.org/10.5194/amt-9-1871-2016, 2016
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A new algorithm allowed to retrieve aerosol optical depths from a Brewer spectrophotometer in Athens with excellent agreement with AERONET. The instrument radiometric stability and the performances of in situ Langley extrapolations as a way to track it are investigated. Potential sources of error and recommendations to operators are reported. MkIV Brewers represent a great source of information about aerosols in the past decades and a promising worldwide network for coordinated AOD measurements.
Luca Egli, Julian Gröbner, Gregor Hülsen, Luciano Bachmann, Mario Blumthaler, Jimmy Dubard, Marina Khazova, Richard Kift, Kees Hoogendijk, Antonio Serrano, Andrew Smedley, and José-Manuel Vilaplana
Atmos. Meas. Tech., 9, 1553–1567, https://doi.org/10.5194/amt-9-1553-2016, https://doi.org/10.5194/amt-9-1553-2016, 2016
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Array spectroradiometers are small, light, robust and cost-effective instruments, and are increasingly used for atmospheric measurements. The quality of array spectroradiometers is assessed for the reliable quantification of ultraviolet radiation (UV) in order to monitor the exposure of UV radiation to human health. The study shows that reliable UV measurements with these instruments are limited for observations around noon and show large biases in the morning and evening.
África Barreto, Emilio Cuevas, María-José Granados-Muñoz, Lucas Alados-Arboledas, Pedro M. Romero, Julian Gröbner, Natalia Kouremeti, Antonio F. Almansa, Tom Stone, Carlos Toledano, Roberto Román, Mikhail Sorokin, Brent Holben, Marius Canini, and Margarita Yela
Atmos. Meas. Tech., 9, 631–654, https://doi.org/10.5194/amt-9-631-2016, https://doi.org/10.5194/amt-9-631-2016, 2016
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This paper presents the new photometer CE318-T, able to perform daytime and
night-time photometric measurements using the sun and the moon as light
sources. This new device permits a complete cycle of diurnal aerosol and water vapour measurements to be extracted, valuable to enhance atmospheric monitoring. We have also highlighted the ability of this new device to capture short-term atmospheric variations, critical for climate studies.
Y. Bühler, M. Marty, L. Egli, J. Veitinger, T. Jonas, P. Thee, and C. Ginzler
The Cryosphere, 9, 229–243, https://doi.org/10.5194/tc-9-229-2015, https://doi.org/10.5194/tc-9-229-2015, 2015
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We are able to map snow depth over large areas ( > 100km2) using airborne digital photogrammetry. Digital photogrammetry is more economical than airborne Laser Scanning but slightly less accurate. Comparisons to independent snow depth measurements reveal an accuracy of about 30cm. Spatial continuous mapping of snow depth is a major step forward compared to point measurements usually applied today. Limitations are steep slopes (> 50°) and areas covered by trees and scrubs.
M. Lothon, F. Lohou, D. Pino, F. Couvreux, E. R. Pardyjak, J. Reuder, J. Vilà-Guerau de Arellano, P Durand, O. Hartogensis, D. Legain, P. Augustin, B. Gioli, D. H. Lenschow, I. Faloona, C. Yagüe, D. C. Alexander, W. M. Angevine, E Bargain, J. Barrié, E. Bazile, Y. Bezombes, E. Blay-Carreras, A. van de Boer, J. L. Boichard, A. Bourdon, A. Butet, B. Campistron, O. de Coster, J. Cuxart, A. Dabas, C. Darbieu, K. Deboudt, H. Delbarre, S. Derrien, P. Flament, M. Fourmentin, A. Garai, F. Gibert, A. Graf, J. Groebner, F. Guichard, M. A. Jiménez, M. Jonassen, A. van den Kroonenberg, V. Magliulo, S. Martin, D. Martinez, L. Mastrorillo, A. F. Moene, F. Molinos, E. Moulin, H. P. Pietersen, B. Piguet, E. Pique, C. Román-Cascón, C. Rufin-Soler, F. Saïd, M. Sastre-Marugán, Y. Seity, G. J. Steeneveld, P. Toscano, O. Traullé, D. Tzanos, S. Wacker, N. Wildmann, and A. Zaldei
Atmos. Chem. Phys., 14, 10931–10960, https://doi.org/10.5194/acp-14-10931-2014, https://doi.org/10.5194/acp-14-10931-2014, 2014
S. Kazadzis, I. Veselovskii, V. Amiridis, J. Gröbner, A. Suvorina, S. Nyeki, E. Gerasopoulos, N. Kouremeti, M. Taylor, A. Tsekeri, and C. Wehrli
Atmos. Meas. Tech., 7, 2013–2025, https://doi.org/10.5194/amt-7-2013-2014, https://doi.org/10.5194/amt-7-2013-2014, 2014
M. Taylor, S. Kazadzis, and E. Gerasopoulos
Atmos. Meas. Tech., 7, 839–858, https://doi.org/10.5194/amt-7-839-2014, https://doi.org/10.5194/amt-7-839-2014, 2014
C. S. Zerefos, P. Tetsis, A. Kazantzidis, V. Amiridis, S. C. Zerefos, J. Luterbacher, K. Eleftheratos, E. Gerasopoulos, S. Kazadzis, and A. Papayannis
Atmos. Chem. Phys., 14, 2987–3015, https://doi.org/10.5194/acp-14-2987-2014, https://doi.org/10.5194/acp-14-2987-2014, 2014
A. Gkikas, N. Hatzianastassiou, N. Mihalopoulos, V. Katsoulis, S. Kazadzis, J. Pey, X. Querol, and O. Torres
Atmos. Chem. Phys., 13, 12135–12154, https://doi.org/10.5194/acp-13-12135-2013, https://doi.org/10.5194/acp-13-12135-2013, 2013
A. Stenke, C. R. Hoyle, B. Luo, E. Rozanov, J. Gröbner, L. Maag, S. Brönnimann, and T. Peter
Atmos. Chem. Phys., 13, 9713–9729, https://doi.org/10.5194/acp-13-9713-2013, https://doi.org/10.5194/acp-13-9713-2013, 2013
T. Egorova, E. Rozanov, J. Gröbner, M. Hauser, and W. Schmutz
Atmos. Chem. Phys., 13, 3811–3823, https://doi.org/10.5194/acp-13-3811-2013, https://doi.org/10.5194/acp-13-3811-2013, 2013
A. V. Lindfors, N. Kouremeti, A. Arola, S. Kazadzis, A. F. Bais, and A. Laaksonen
Atmos. Chem. Phys., 13, 3733–3741, https://doi.org/10.5194/acp-13-3733-2013, https://doi.org/10.5194/acp-13-3733-2013, 2013
Related subject area
Subject: Aerosols | Technique: Remote Sensing | Topic: Validation and Intercomparisons
Estimating hourly ground-level aerosols using Geostationary Environment Monitoring Spectrometer aerosol optical depth: a machine learning approach
Performance and evaluation of remote sensing satellites for monitoring dust weather in East Asia
Aerosol effects on day-ahead solar radiation forecasting
Decoupling the PBL Height, the Mixing Layer Height, and the Aerosol Layer Top in LiDAR Measurements over Chiang Mai, Northern Thailand
A global perspective on CO2 satellite observations in high AOD conditions
Cross validations of the Aeolus aerosol products and new developments with airborne high spectral resolution lidar measurements above the Tropical Atlantic during JATAC
Aerosol layer height (ALH) retrievals from oxygen absorption bands: intercomparison and validation among different satellite platforms, GEMS, EPIC, and TROPOMI
Assessment of ACE-MAESTRO v3.13 multi-wavelength stratospheric aerosol extinction measurements
Intercomparison of aerosol optical depth retrievals from GAW-PFR and SKYNET sun photometer networks and the effect of calibration
Evaluation of Aeolus feature mask and particle extinction coefficient profile products using CALIPSO data
Assessment of the impact of NO2 contribution on aerosol-optical-depth measurements at several sites worldwide
Improved mean field estimates from the Geostationary Environment Monitoring Spectrometer (GEMS) Level-3 aerosol optical depth (L3 AOD) product: using spatiotemporal variability
Evaluation of on-site calibration procedures for SKYNET Prede POM sun–sky photometers
Aerosol optical property measurement using the orbiting high-spectral-resolution lidar on board the DQ-1 satellite: retrieval and validation
Regional validation of the solar irradiance tool SolaRes in clear-sky conditions, with a focus on the aerosol module
An empirical characterization of the aerosol Ångström exponent interpolation bias using SAGE III/ISS data
Retrievals of aerosol optical depth over the western North Atlantic Ocean during ACTIVATE
Characterization of dust aerosols from ALADIN and CALIOP measurements
Lidar depolarization characterization using a reference system
Algorithm evaluation for polarimetric remote sensing of atmospheric aerosols
Validation of initial observation from the first spaceborne high-spectral-resolution lidar with a ground-based lidar network
Ozone and aerosol optical depth retrievals using the ultraviolet multi-filter rotating shadow-band radiometer
Expanding the coverage of Multi-angle Imaging SpectroRadiometer (MISR) aerosol retrievals over shallow, turbid, and eutrophic waters
Aerosol properties derived from ground-based Fourier transform spectra within the COllaborative Carbon Column Observing Network
Spectral aerosol optical depth from SI-traceable spectral solar irradiance measurements
Quality assessment of aerosol lidars at 1064 nm in the framework of the MEMO campaign
Satellite-based, top-down approach for the adjustment of aerosol precursor emissions over East Asia: the TROPOspheric Monitoring Instrument (TROPOMI) NO2 product and the Geostationary Environment Monitoring Spectrometer (GEMS) aerosol optical depth (AOD) data fusion product and its proxy
Assessment of severe aerosol events from NASA MODIS and VIIRS aerosol products for data assimilation and climate continuity
First assessment of Aeolus Standard Correct Algorithm particle backscatter coefficient retrievals in the eastern Mediterranean
Remote sensing of aerosol water fraction, dry size distribution and soluble fraction using multi-angle, multi-spectral polarimetry
Estimates of remote sensing retrieval errors by the GRASP algorithm: application to ground-based observations, concept and validation
Extended validation and evaluation of the OLCI–SLSTR SYNERGY aerosol product (SY_2_AOD) on Sentinel-3
Performance evaluation for retrieving aerosol optical depth from the Directional Polarimetric Camera (DPC) based on the GRASP algorithm
Assessment of tropospheric CALIPSO Version 4.2 aerosol types over the ocean using independent CALIPSO–SODA lidar ratios
Real-time UV index retrieval in Europe using Earth observation-based techniques: system description and quality assessment
Evaluation of UV–visible MAX-DOAS aerosol profiling products by comparison with ceilometer, sun photometer, and in situ observations in Vienna, Austria
Experimental assessment of a micro-pulse lidar system in comparison with reference lidar measurements for aerosol optical properties retrieval
Characterization of aerosol size properties from measurements of spectral optical depth: a global validation of the GRASP-AOD code using long-term AERONET data
Retrieval of aerosol fine-mode fraction over China from satellite multiangle polarized observations: validation and comparison
Retrieval and evaluation of tropospheric-aerosol extinction profiles using multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements over Athens, Greece
Empirically derived parameterizations of the direct aerosol radiative effect based on ORACLES aircraft observations
TROPOMI aerosol products: evaluation and observations of synoptic-scale carbonaceous aerosol plumes during 2018–2020
Combining low-cost, surface-based aerosol monitors with size-resolved satellite data for air quality applications
Interannual and seasonal variations in the aerosol optical depth of the atmosphere in two regions of Spitsbergen (2002–2018)
Evaluation of UV aerosol retrievals from an ozone lidar
Aerosol data assimilation in the MOCAGE chemical transport model during the TRAQA/ChArMEx campaign: lidar observations
Application of low-cost fine particulate mass monitors to convert satellite aerosol optical depth to surface concentrations in North America and Africa
Evaluation of the OMPS/LP stratospheric aerosol extinction product using SAGE III/ISS observations
A fast visible-wavelength 3D radiative transfer model for numerical weather prediction visualization and forward modeling
A first comparison of TROPOMI aerosol layer height (ALH) to CALIOP data
Sungmin O, Ji Won Yoon, and Seon Ki Park
Atmos. Meas. Tech., 18, 1471–1484, https://doi.org/10.5194/amt-18-1471-2025, https://doi.org/10.5194/amt-18-1471-2025, 2025
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Air pollutants such as particulate matter with diameters of 10 µm and 2.5 µm or less (PM10 and PM2.5) can cause adverse public health and environment effects; therefore their regular monitoring is crucial to keep pollutant concentrations under control. Our study demonstrates the potential of high-resolution aerosol optical depth (AOD) data from the Geostationary Environment Monitoring Spectrometer (GEMS) satellite to estimate ground-level PM concentrations using machine learning models.
Yuanyuan Zhang, Ning Wang, and Shuanggen Jin
EGUsphere, https://doi.org/10.5194/egusphere-2025-992, https://doi.org/10.5194/egusphere-2025-992, 2025
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Satellite remote sensing helps monitor dust storms in East Asia, but its effectiveness is still limited. Our study compared five satellite products that use ground-based PM10 data. Most products agreed on the daily dust distribution, with AAI performing best under cloud cover. MODIS AOD performed best, followed by Himawari-8 AOD. This study improves dust and sparseness monitoring in East Asia.
Xinyuan Hou, Kyriakoula Papachristopoulou, and Stelios Kazadzis
EGUsphere, https://doi.org/10.5194/egusphere-2025-891, https://doi.org/10.5194/egusphere-2025-891, 2025
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We analyzed aerosol ground measurements and model based aerosol optical depth (AOD) forecasts to study variations in AOD at different global sites. We compared day-ahead AOD forecast methods and assessed their impact on forecasting clear-sky direct normal irradiance (DNI). While none of the methods accurately forecast DNI within 5 %, most sites showed a DNI deviation within 20 %, especially at sites with urban-industrial aerosols.
Ronald Macatangay, Thiranan Sonkaew, Sherin Hassan Bran, Worapop Thongsame, Titaporn Supasri, Mana Panya, Jeerasak Longmali, Raman Solanki, Ben Svasti Thomson, and Achim Haug
EGUsphere, https://doi.org/10.5194/egusphere-2025-630, https://doi.org/10.5194/egusphere-2025-630, 2025
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Air pollution affects climate and health, but accurately measuring how pollutants mix in the atmosphere remains challenging. In Chiang Mai, Thailand, we developed a new LiDAR-based method to better distinguish key atmospheric layers by incorporating temperature-based adjustments. This improves accuracy, especially at night, compared to traditional techniques. Our findings help refine air quality models and provide better data for tackling pollution in Southeast Asia.
Timo H. Virtanen, Anu-Maija Sundström, Elli Suhonen, Antti Lipponen, Antti Arola, Christopher O'Dell, Robert R. Nelson, and Hannakaisa Lindqvist
Atmos. Meas. Tech., 18, 929–952, https://doi.org/10.5194/amt-18-929-2025, https://doi.org/10.5194/amt-18-929-2025, 2025
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We find that small particles suspended in the air (aerosols) affect the satellite observations of carbon dioxide (CO2) made by the Orbiting Carbon Observatory-2 satellite instrument. Satellite estimates of CO2 appear to be too high for clean areas and too low for polluted areas. Our results show that CO2 and aerosols are often co-emitted, and this is partly masked out in the current retrievals. Correctly accounting for the aerosol effect is important for CO2 emission estimates by satellites.
Dimitri Trapon, Holger Baars, Athena Floutsi, Sebastian Bley, Adrien Lacour, Thomas Flament, Alain Dabas, Amin R. Nehrir, Frithjof Ehlers, and Dorit Huber
EGUsphere, https://doi.org/10.5194/egusphere-2025-462, https://doi.org/10.5194/egusphere-2025-462, 2025
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The study highlights how aerosol measurements from aircraft can be used in synergy with ground-based observations to validate the ESA's AEOLUS satellite aerosol product above the Tropical Atlantic. For the first time, collocated sections of the troposphere up to 626 km long are crossed. Combining measurements from satellite, aircraft, and ground-based instruments allows to characterize the optical properties of the observed dust particles emitted from the Sahara Desert.
Hyerim Kim, Xi Chen, Jun Wang, Zhendong Lu, Meng Zhou, Gregory R. Carmichael, Sang Seo Park, and Jhoon Kim
Atmos. Meas. Tech., 18, 327–349, https://doi.org/10.5194/amt-18-327-2025, https://doi.org/10.5194/amt-18-327-2025, 2025
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We compare passive aerosol layer height (ALH) retrievals from the Earth Polychromatic Imaging Camera (EPIC), TROPOspheric Monitoring Instrument (TROPOMI), and Geostationary Environment Monitoring Spectrometer (GEMS) with lidar. GEMS shows a lower correlation (R = 0.64) than EPIC and TROPOMI (R > 0.7) but with minimal bias (0.1 km vs. overestimated by ~0.8 km). GEMS performance is improved for an ultraviolet aerosol index ≥ 3. EPIC and GEMS ALH diurnal variation differs slightly.
Sujan Khanal, Matthew Toohey, Adam Bourassa, C. Thomas McElroy, Christopher Sioris, and Kaley A. Walker
EGUsphere, https://doi.org/10.5194/egusphere-2024-3286, https://doi.org/10.5194/egusphere-2024-3286, 2024
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Measurements of stratospheric aerosol from the MAESTRO instrument are compared to other measurements to assess their scientific value. We find that medians of MAESTRO measurements binned by month and latitude show reasonable correlation with other data sets, with notable increases after volcanic eruptions, and that biases in the data can be alleviated through a simple correction technique. Used with care, MAESTRO aerosol measurements provide information that can complement other data sets.
Angelos Karanikolas, Natalia Kouremeti, Monica Campanelli, Victor Estellés, Masahiro Momoi, Gaurav Kumar, Stephan Nyeki, and Stelios Kazadzis
Atmos. Meas. Tech., 17, 6085–6105, https://doi.org/10.5194/amt-17-6085-2024, https://doi.org/10.5194/amt-17-6085-2024, 2024
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Different sun photometer networks use different instruments, post-processing algorithms and calibration protocols for aerosol optical depth (AOD) retrieval. Such differences can affect the homogeneity and comparability of their measurements. In this study, we assess the homogeneity between the sun photometer networks GAW-PFR and SKYNET, analysing common measurements during three campaigns between 2017–2021, and investigate the main cause of the differences.
Ping Wang, David Patrick Donovan, Gerd-Jan van Zadelhoff, Jos de Kloe, Dorit Huber, and Katja Reissig
Atmos. Meas. Tech., 17, 5935–5955, https://doi.org/10.5194/amt-17-5935-2024, https://doi.org/10.5194/amt-17-5935-2024, 2024
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We describe the new feature mask (AEL-FM) and aerosol profile retrieval (AEL-PRO) algorithms developed for Aeolus lidar and present the evaluation of the Aeolus products using CALIPSO data for dust aerosols over Africa. We have found that Aeolus and CALIPSO show similar aerosol patterns in the collocated orbits and have good agreement for the extinction coefficients for the dust aerosols, especially for the cloud-free scenes. The finding is applicable to Aeolus L2A product Baseline 17.
Akriti Masoom, Stelios Kazadzis, Masimo Valeri, Ioannis-Panagiotis Raptis, Gabrielle Brizzi, Kyriakoula Papachristopoulou, Francesca Barnaba, Stefano Casadio, Axel Kreuter, and Fabrizio Niro
Atmos. Meas. Tech., 17, 5525–5549, https://doi.org/10.5194/amt-17-5525-2024, https://doi.org/10.5194/amt-17-5525-2024, 2024
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Aerosols, which have a wide impact on climate, radiative forcing, and human health, are widely represented by aerosol optical depth (AOD). AOD retrievals require Rayleigh scattering and atmospheric absorption (ozone, NO2, etc.) corrections. We analysed the NO2 (which has a high spatiotemporal variation) uncertainty impact on AOD retrievals using the synergy of co-located ground-based instruments with a long-term dataset at worldwide sites and found significant AOD over- or underestimations.
Sooyon Kim, Yeseul Cho, Hanjeong Ki, Seyoung Park, Dagun Oh, Seungjun Lee, Yeonghye Cho, Jhoon Kim, Wonjin Lee, Jaewoo Park, Ick Hoon Jin, and Sangwook Kang
Atmos. Meas. Tech., 17, 5221–5241, https://doi.org/10.5194/amt-17-5221-2024, https://doi.org/10.5194/amt-17-5221-2024, 2024
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This paper describes new work that improves the processing of GEMS AOD data. First, we enhance the inverse-distance-weighting algorithm by incorporating quality flag information, assigning weights that are inversely proportional to the number of unreliable grids. Second, we leverage a spatiotemporal merging method to address both spatial and temporal variability. Finally, we estimate the mean field values for GEMS AOD data, enhancing our understanding of the impact of aerosols on climate change.
Monica Campanelli, Victor Estellés, Gaurav Kumar, Teruyuki Nakajima, Masahiro Momoi, Julian Gröbner, Stelios Kazadzis, Natalia Kouremeti, Angelos Karanikolas, Africa Barreto, Saulius Nevas, Kerstin Schwind, Philipp Schneider, Iiro Harju, Petri Kärhä, Henri Diémoz, Rei Kudo, Akihiro Uchiyama, Akihiro Yamazaki, Anna Maria Iannarelli, Gabriele Mevi, Annalisa Di Bernardino, and Stefano Casadio
Atmos. Meas. Tech., 17, 5029–5050, https://doi.org/10.5194/amt-17-5029-2024, https://doi.org/10.5194/amt-17-5029-2024, 2024
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To retrieve columnar aerosol properties from sun photometers, some calibration factors are needed. The on-site calibrations, performed as frequently as possible to monitor changes in the machine conditions, allow operators to track and evaluate the calibration status on a continuous basis, reducing the data gaps incurred by the periodic shipments for performing centralized calibrations. The performance of the on-site calibration procedures was evaluated, providing very good results.
Chenxing Zha, Lingbing Bu, Zhi Li, Qin Wang, Ahmad Mubarak, Pasindu Liyanage, Jiqiao Liu, and Weibiao Chen
Atmos. Meas. Tech., 17, 4425–4443, https://doi.org/10.5194/amt-17-4425-2024, https://doi.org/10.5194/amt-17-4425-2024, 2024
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China has launched the atmospheric environment monitoring satellite DQ-1, which consists of an advanced lidar system. Our research presents a retrieval algorithm of the DQ-1 lidar system, and the retrieval results are consistent with other datasets. We also use the DQ-1 dataset to investigate dust and volcanic aerosols. This research shows that the DQ-1 lidar system can accurately measure the Earth's atmosphere and has potential for scientific applications.
Thierry Elias, Nicolas Ferlay, Gabriel Chesnoiu, Isabelle Chiapello, and Mustapha Moulana
Atmos. Meas. Tech., 17, 4041–4063, https://doi.org/10.5194/amt-17-4041-2024, https://doi.org/10.5194/amt-17-4041-2024, 2024
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In the solar energy application field, it is key to simulate solar resources anywhere on the globe. We conceived the Solar Resource estimate (SolaRes) tool to provide precise and accurate estimates of solar resources for any solar plant technology. We present the validation of SolaRes by comparing estimates with measurements made on two ground-based platforms in northern France for 2 years at 1 min resolution. Validation is done in clear-sky conditions where aerosols are the main factors.
Robert P. Damadeo, Viktoria F. Sofieva, Alexei Rozanov, and Larry W. Thomason
Atmos. Meas. Tech., 17, 3669–3678, https://doi.org/10.5194/amt-17-3669-2024, https://doi.org/10.5194/amt-17-3669-2024, 2024
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Comparing different aerosol data sets for scientific studies often requires converting aerosol extinction data between different wavelengths. A common approximation for the spectral behavior of aerosol is the Ångström formula; however, this introduces biases. Using measurements across many different wavelengths from a single instrument, we derive an empirical relationship to both characterize this bias and offer a correction for other studies that may employ this analysis approach.
Leong Wai Siu, Joseph S. Schlosser, David Painemal, Brian Cairns, Marta A. Fenn, Richard A. Ferrare, Johnathan W. Hair, Chris A. Hostetler, Longlei Li, Mary M. Kleb, Amy Jo Scarino, Taylor J. Shingler, Armin Sorooshian, Snorre A. Stamnes, and Xubin Zeng
Atmos. Meas. Tech., 17, 2739–2759, https://doi.org/10.5194/amt-17-2739-2024, https://doi.org/10.5194/amt-17-2739-2024, 2024
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An unprecedented 3-year aerosol dataset was collected from a recent NASA field campaign over the western North Atlantic Ocean, which offers a special opportunity to evaluate two state-of-the-art remote sensing instruments, one lidar and the other polarimeter, on the same aircraft. Special attention has been paid to validate aerosol optical depth data and their uncertainties when no reference dataset is available. Physical reasons for the disagreement between two instruments are discussed.
Rui Song, Adam Povey, and Roy G. Grainger
Atmos. Meas. Tech., 17, 2521–2538, https://doi.org/10.5194/amt-17-2521-2024, https://doi.org/10.5194/amt-17-2521-2024, 2024
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In our study, we explored aerosols, tiny atmospheric particles affecting the Earth's climate. Using data from two lidar-equipped satellites, ALADIN and CALIOP, we examined a 2020 Saharan dust event. The newer ALADIN's results aligned with CALIOP's. By merging their data, we corrected CALIOP's discrepancies, enhancing the dust event depiction. This underscores the significance of advanced satellite instruments in aerosol research. Our findings pave the way for upcoming satellite missions.
Alkistis Papetta, Franco Marenco, Maria Kezoudi, Rodanthi-Elisavet Mamouri, Argyro Nisantzi, Holger Baars, Ioana Elisabeta Popovici, Philippe Goloub, Stéphane Victori, and Jean Sciare
Atmos. Meas. Tech., 17, 1721–1738, https://doi.org/10.5194/amt-17-1721-2024, https://doi.org/10.5194/amt-17-1721-2024, 2024
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We propose a method to determine depolarization parameters using observations from a reference instrument at a nearby location, needed for systems where a priori knowledge of cross-talk parameters is not available. It uses three-parameter equations to compare VDR between two co-located lidars at dust and molecular layers. It can be applied retrospectively to existing data acquired during campaigns. Its application to Cimel CE376 corrected VDR bias at high- and low-depolarizing layers.
Otto Hasekamp, Pavel Litvinov, Guangliang Fu, Cheng Chen, and Oleg Dubovik
Atmos. Meas. Tech., 17, 1497–1525, https://doi.org/10.5194/amt-17-1497-2024, https://doi.org/10.5194/amt-17-1497-2024, 2024
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Aerosols are particles in the atmosphere that cool the climate by reflecting and absorbing sunlight (direct effect) and changing cloud properties (indirect effect). The scale of aerosol cooling is uncertain, hampering accurate climate predictions. We compare two algorithms for the retrieval of aerosol properties from multi-angle polarimetric measurements: Generalized Retrieval of Atmosphere and Surface Properties (GRASP) and Remote sensing of Trace gas and Aerosol Products (RemoTAP).
Qiantao Liu, Zhongwei Huang, Jiqiao Liu, Weibiao Chen, Qingqing Dong, Songhua Wu, Guangyao Dai, Meishi Li, Wuren Li, Ze Li, Xiaodong Song, and Yuan Xie
Atmos. Meas. Tech., 17, 1403–1417, https://doi.org/10.5194/amt-17-1403-2024, https://doi.org/10.5194/amt-17-1403-2024, 2024
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The achieved results revealed that the ACDL observations were in good agreement with the ground-based lidar measurements during dust events. The heights of cloud top and bottom from these two measurements were well matched and comparable. This study proves that the ACDL provides reliable observations of aerosol and cloud in the presence of various climatic conditions, which helps to further evaluate the impacts of aerosol on climate and the environment, as well as on the ecosystem in the future.
Joseph Michalsky and Glen McConville
Atmos. Meas. Tech., 17, 1017–1022, https://doi.org/10.5194/amt-17-1017-2024, https://doi.org/10.5194/amt-17-1017-2024, 2024
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The ozone in the atmosphere is measured by looking at the sun and measuring how diminished the light in the ultraviolet is relative to how bright it is above the Earth's atmosphere. This typically uses spectral instruments that are either costly or no longer manufactured. This paper uses a relatively inexpensive interference filter instrument to perform the same task. Daily ozone measurements with the latter and this filter instrument are compared. Aerosols are calculated as a by-product.
Robert R. Nelson, Marcin L. Witek, Michael J. Garay, Michael A. Bull, James A. Limbacher, Ralph A. Kahn, and David J. Diner
Atmos. Meas. Tech., 16, 4947–4960, https://doi.org/10.5194/amt-16-4947-2023, https://doi.org/10.5194/amt-16-4947-2023, 2023
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Shallow and coastal waters are nutrient-rich and turbid due to runoff. They are also located in areas where the atmosphere has more aerosols than open-ocean waters. NASA's Multi-angle Imaging SpectroRadiometer (MISR) has been monitoring aerosols for over 23 years but does not report results over shallow waters. We developed a new algorithm that uses all four of MISR’s bands and considers light leaving water surfaces. This algorithm performs well and increases over-water measurements by over 7 %.
Óscar Alvárez, África Barreto, Omaira E. García, Frank Hase, Rosa D. García, Julian Gröbner, Sergio F. León-Luis, Eliezer Sepúlveda, Virgilio Carreño, Antonio Alcántara, Ramón Ramos, A. Fernando Almansa, Stelios Kazadzis, Noémie Taquet, Carlos Toledano, and Emilio Cuevas
Atmos. Meas. Tech., 16, 4861–4884, https://doi.org/10.5194/amt-16-4861-2023, https://doi.org/10.5194/amt-16-4861-2023, 2023
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In this work, we have extended the capabilities of a portable Fourier transform infrared (FTIR) instrument, which was originally designed to provide high-quality greenhouse gas monitoring within COCCON (COllaborative Carbon Column Observing Network). The extension allows the spectrometer to now also provide coincidentally column-integrated aerosol information. This addition of a reference instrument to a global network will be utilised to enhance our understanding of atmospheric chemistry.
Julian Gröbner, Natalia Kouremeti, Gregor Hülsen, Ralf Zuber, Mario Ribnitzky, Saulius Nevas, Peter Sperfeld, Kerstin Schwind, Philipp Schneider, Stelios Kazadzis, África Barreto, Tom Gardiner, Kavitha Mottungan, David Medland, and Marc Coleman
Atmos. Meas. Tech., 16, 4667–4680, https://doi.org/10.5194/amt-16-4667-2023, https://doi.org/10.5194/amt-16-4667-2023, 2023
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Spectral solar irradiance measurements traceable to the International System of Units (SI) allow for intercomparability between instruments and for their validation according to metrological standards. Here we also validate and reduce the uncertainties of the top-of-atmosphere TSIS-1 Hybrid Solar Reference Spectrum (HSRS). The management of large networks, e.g. AERONET or GAW-PFR, will benefit from reducing logistical overhead, improving their resilience and achieving metrological traceability.
Longlong Wang, Zhenping Yin, Zhichao Bu, Anzhou Wang, Song Mao, Yang Yi, Detlef Müller, Yubao Chen, and Xuan Wang
Atmos. Meas. Tech., 16, 4307–4318, https://doi.org/10.5194/amt-16-4307-2023, https://doi.org/10.5194/amt-16-4307-2023, 2023
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We report the lidar inter-comparison results with a reference lidar at 1064 nm, in order to homogenize the signals provided by different lidar systems for establishing a lidar network in China. The profiles of relative deviation of lidar signals are less than 5 % within 500–2000 m and 10 % within 2000–5000 m, increasing confidence in the reliability of the signals provided by each lidar system in the channels at 1064 nm for a future lidar network in China.
Jincheol Park, Jia Jung, Yunsoo Choi, Hyunkwang Lim, Minseok Kim, Kyunghwa Lee, Yun Gon Lee, and Jhoon Kim
Atmos. Meas. Tech., 16, 3039–3057, https://doi.org/10.5194/amt-16-3039-2023, https://doi.org/10.5194/amt-16-3039-2023, 2023
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In response to the recent release of new geostationary platform-derived observational data generated by the Geostationary Environment Monitoring Spectrometer (GEMS) and its sister instruments, this study utilized the GEMS data fusion product and its proxy data in adjusting aerosol precursor emissions over East Asia. The use of spatiotemporally more complete observation references in updating the emissions resulted in more promising model performances in estimating aerosol loadings in East Asia.
Amanda Gumber, Jeffrey S. Reid, Robert E. Holz, Thomas F. Eck, N. Christina Hsu, Robert C. Levy, Jianglong Zhang, and Paolo Veglio
Atmos. Meas. Tech., 16, 2547–2573, https://doi.org/10.5194/amt-16-2547-2023, https://doi.org/10.5194/amt-16-2547-2023, 2023
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The purpose of this study is to create and evaluate a gridded dataset composed of multiple satellite instruments and algorithms to be used for data assimilation. An important part of aerosol data assimilation is having consistent measurements, especially for severe aerosol events. This study evaluates 4 years of data from MODIS, VIIRS, and AERONET with a focus on aerosol severe event detection from a regional and global perspective.
Antonis Gkikas, Anna Gialitaki, Ioannis Binietoglou, Eleni Marinou, Maria Tsichla, Nikolaos Siomos, Peristera Paschou, Anna Kampouri, Kalliopi Artemis Voudouri, Emmanouil Proestakis, Maria Mylonaki, Christina-Anna Papanikolaou, Konstantinos Michailidis, Holger Baars, Anne Grete Straume, Dimitris Balis, Alexandros Papayannis, Tomasso Parrinello, and Vassilis Amiridis
Atmos. Meas. Tech., 16, 1017–1042, https://doi.org/10.5194/amt-16-1017-2023, https://doi.org/10.5194/amt-16-1017-2023, 2023
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We perform an assessment analysis of the Aeolus Standard Correct Algorithm (SCA) backscatter coefficient retrievals against reference observations acquired at three Greek lidar stations (Athens, Thessaloniki and Antikythera) of the PANACEA network. Overall, 43 cases are analysed, whereas specific aerosol scenarios in the vicinity of Antikythera island (SW Greece) are emphasised. All key Cal/Val aspects and recommendations, and the ongoing related activities, are thoroughly discussed.
Bastiaan van Diedenhoven, Otto P. Hasekamp, Brian Cairns, Gregory L. Schuster, Snorre Stamnes, Michael Shook, and Luke Ziemba
Atmos. Meas. Tech., 15, 7411–7434, https://doi.org/10.5194/amt-15-7411-2022, https://doi.org/10.5194/amt-15-7411-2022, 2022
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The strong variability in the chemistry of atmospheric particulate matter affects the amount of water aerosols absorb and their effect on climate. We present a remote sensing method to determine the amount of water in particulate matter. Its application to airborne instruments indicates that the observed aerosols have rather low water contents and low fractions of soluble particles. Future satellites will be able to yield global aerosol water uptake data.
Milagros E. Herrera, Oleg Dubovik, Benjamin Torres, Tatyana Lapyonok, David Fuertes, Anton Lopatin, Pavel Litvinov, Cheng Chen, Jose Antonio Benavent-Oltra, Juan L. Bali, and Pablo R. Ristori
Atmos. Meas. Tech., 15, 6075–6126, https://doi.org/10.5194/amt-15-6075-2022, https://doi.org/10.5194/amt-15-6075-2022, 2022
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This study deals with the dynamic error estimates of the aerosol-retrieved properties by the GRASP algorithm, which are provided for directly retrieved and derived parameters. Moreover, GRASP provides full covariance matrices that appear to be a useful approach for optimizing observation schemes and retrieval set-ups. The validation of the retrieved dynamic error estimates is done through real and synthetic measurements using sun photometer and lidar observations.
Larisa Sogacheva, Matthieu Denisselle, Pekka Kolmonen, Timo H. Virtanen, Peter North, Claire Henocq, Silvia Scifoni, and Steffen Dransfeld
Atmos. Meas. Tech., 15, 5289–5322, https://doi.org/10.5194/amt-15-5289-2022, https://doi.org/10.5194/amt-15-5289-2022, 2022
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The aim of this study was to provide global characterisation of a new SYNERGY aerosol product derived from the data from the OLCI and SLSTR sensors aboard the Sentinel-3A and Sentinel-3B satellites. Over ocean, the performance of SYNERGY-retrieved AOD is good. Reduced performance over land was expected since the surface reflectance and angular distribution of scattering are more difficult to treat. Validation statistics are often slightly better for S3B and in the Southern Hemisphere.
Shikuan Jin, Yingying Ma, Cheng Chen, Oleg Dubovik, Jin Hong, Boming Liu, and Wei Gong
Atmos. Meas. Tech., 15, 4323–4337, https://doi.org/10.5194/amt-15-4323-2022, https://doi.org/10.5194/amt-15-4323-2022, 2022
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Aerosol parameter retrievals have always been a research focus. In this study, we used an advanced aerosol algorithms (GRASP, developed by Oleg Dubovik) to test the ability of DPC/Gaofen-5 (the first polarized multi-angle payload developed in China) images to obtain aerosol parameters. The results show that DPC/GRASP achieves good results (R > 0.9). This research will contribute to the development of hardware and algorithms for aerosols
Zhujun Li, David Painemal, Gregory Schuster, Marian Clayton, Richard Ferrare, Mark Vaughan, Damien Josset, Jayanta Kar, and Charles Trepte
Atmos. Meas. Tech., 15, 2745–2766, https://doi.org/10.5194/amt-15-2745-2022, https://doi.org/10.5194/amt-15-2745-2022, 2022
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For more than 15 years, CALIPSO has revolutionized our understanding of the role of aerosols in climate. Here we evaluate CALIPSO aerosol typing over the ocean using an independent CALIPSO–CloudSat product. The analysis suggests that CALIPSO correctly categorizes clean marine aerosol over the open ocean, elevated smoke over the SE Atlantic, and dust over the tropical Atlantic. Similarities between clean and dusty marine over the open ocean implies that algorithm modifications are warranted.
Panagiotis G. Kosmopoulos, Stelios Kazadzis, Alois W. Schmalwieser, Panagiotis I. Raptis, Kyriakoula Papachristopoulou, Ilias Fountoulakis, Akriti Masoom, Alkiviadis F. Bais, Julia Bilbao, Mario Blumthaler, Axel Kreuter, Anna Maria Siani, Kostas Eleftheratos, Chrysanthi Topaloglou, Julian Gröbner, Bjørn Johnsen, Tove M. Svendby, Jose Manuel Vilaplana, Lionel Doppler, Ann R. Webb, Marina Khazova, Hugo De Backer, Anu Heikkilä, Kaisa Lakkala, Janusz Jaroslawski, Charikleia Meleti, Henri Diémoz, Gregor Hülsen, Barbara Klotz, John Rimmer, and Charalampos Kontoes
Atmos. Meas. Tech., 14, 5657–5699, https://doi.org/10.5194/amt-14-5657-2021, https://doi.org/10.5194/amt-14-5657-2021, 2021
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Large-scale retrievals of the ultraviolet index (UVI) in real time by exploiting the modern Earth observation data and techniques are capable of forming operational early warning systems that raise awareness among citizens of the health implications of high UVI doses. In this direction a novel UVI operating system, the so-called UVIOS, was introduced for massive outputs, while its performance was tested against ground-based measurements revealing a dependence on the input quality and resolution.
Stefan F. Schreier, Tim Bösch, Andreas Richter, Kezia Lange, Michael Revesz, Philipp Weihs, Mihalis Vrekoussis, and Christoph Lotteraner
Atmos. Meas. Tech., 14, 5299–5318, https://doi.org/10.5194/amt-14-5299-2021, https://doi.org/10.5194/amt-14-5299-2021, 2021
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This paper reports on the evaluation of aerosol profiling products retrieved from ground-based MAX-DOAS instruments using the BOREAS algorithm. Aerosol extinction profiles, near-surface aerosol extinction, and aerosol optical depth are compared to measurements collected with ceilometer, sun photometer, and in situ instruments. We show that these MAX-DOAS aerosol profiling products provide useful information to study spatial and temporal variations above the urban area of Vienna.
Carmen Córdoba-Jabonero, Albert Ansmann, Cristofer Jiménez, Holger Baars, María-Ángeles López-Cayuela, and Ronny Engelmann
Atmos. Meas. Tech., 14, 5225–5239, https://doi.org/10.5194/amt-14-5225-2021, https://doi.org/10.5194/amt-14-5225-2021, 2021
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An experimental assessment of a polarized micro-pulse lidar (P-MPL) in comparison to reference lidars is presented regarding the retrieval of aerosol optical properties. The evaluation is focused on both the optimally determined overlap function and volume linear depolarization ratio. A P-MPL overlap must be regularly estimated to derive suitable aerosol products (backscatter, extinction, and particle depolarization ratio). This methodology can be easily applied to other P-MPL systems.
Benjamin Torres and David Fuertes
Atmos. Meas. Tech., 14, 4471–4506, https://doi.org/10.5194/amt-14-4471-2021, https://doi.org/10.5194/amt-14-4471-2021, 2021
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The article shows the capacity of the new GRASP-AOD approach to be used for large datasets of aerosol optical depth from ground-based observations, through a comparison with standard AERONET codes. This new approach reduces the requirements in terms of measurements (no need of scattering information) to derive some basic aerosol size and optical properties. A broad use of this algorithm would increase the datasets of aerosol properties from ground-based observations.
Yang Zhang, Zhengqiang Li, Zhihong Liu, Yongqian Wang, Lili Qie, Yisong Xie, Weizhen Hou, and Lu Leng
Atmos. Meas. Tech., 14, 1655–1672, https://doi.org/10.5194/amt-14-1655-2021, https://doi.org/10.5194/amt-14-1655-2021, 2021
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The aerosol fine-mode fraction (FMF) is an important parameter reflecting the content of man-made aerosols. This study carried out the retrieval of FMF in China based on multi-angle polarization data and validated the results. The results of this study can contribute to the FMF retrieval algorithm of multi-angle polarization sensors. At the same time, a high-precision FMF dataset of China was obtained, which can provide basic data for atmospheric environment research.
Myrto Gratsea, Tim Bösch, Panagiotis Kokkalis, Andreas Richter, Mihalis Vrekoussis, Stelios Kazadzis, Alexandra Tsekeri, Alexandros Papayannis, Maria Mylonaki, Vassilis Amiridis, Nikos Mihalopoulos, and Evangelos Gerasopoulos
Atmos. Meas. Tech., 14, 749–767, https://doi.org/10.5194/amt-14-749-2021, https://doi.org/10.5194/amt-14-749-2021, 2021
Sabrina P. Cochrane, K. Sebastian Schmidt, Hong Chen, Peter Pilewskie, Scott Kittelman, Jens Redemann, Samuel LeBlanc, Kristina Pistone, Meloë Kacenelenbogen, Michal Segal Rozenhaimer, Yohei Shinozuka, Connor Flynn, Amie Dobracki, Paquita Zuidema, Steven Howell, Steffen Freitag, and Sarah Doherty
Atmos. Meas. Tech., 14, 567–593, https://doi.org/10.5194/amt-14-567-2021, https://doi.org/10.5194/amt-14-567-2021, 2021
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Based on observations from the 2016 and 2017 field campaigns of ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS), this work establishes an observationally driven link from mid-visible aerosol optical depth (AOD) and other scene parameters to broadband shortwave irradiance (and by extension the direct aerosol radiative effect, DARE). The majority of the case-to-case DARE variability within the ORACLES dataset is attributable to the dependence on AOD and scene albedo.
Omar Torres, Hiren Jethva, Changwoo Ahn, Glen Jaross, and Diego G. Loyola
Atmos. Meas. Tech., 13, 6789–6806, https://doi.org/10.5194/amt-13-6789-2020, https://doi.org/10.5194/amt-13-6789-2020, 2020
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TROPOMI measures the quantity of small suspended particles (aerosols). We describe initial results of aerosol measurements using a NASA algorithm that retrieves the UV aerosol index, aerosol optical depth, and single-scattering albedo. An evaluation of derived products using sun-photometer observations shows close agreement. We also use these results to discuss important biomass burning and wildfire events around the world that got the attention of scientists and news media alike.
Priyanka deSouza, Ralph A. Kahn, James A. Limbacher, Eloise A. Marais, Fábio Duarte, and Carlo Ratti
Atmos. Meas. Tech., 13, 5319–5334, https://doi.org/10.5194/amt-13-5319-2020, https://doi.org/10.5194/amt-13-5319-2020, 2020
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This paper presents a novel method to constrain the size distribution derived from low-cost optical particle counters (OPCs) using satellite data to develop higher-quality particulate matter (PM) estimates. Such estimates can enable cities that do not have access to expensive reference air quality monitors, especially those in the global south, to develop effective air quality management plans.
Dmitry M. Kabanov, Christoph Ritter, and Sergey M. Sakerin
Atmos. Meas. Tech., 13, 5303–5317, https://doi.org/10.5194/amt-13-5303-2020, https://doi.org/10.5194/amt-13-5303-2020, 2020
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Long-term photometer measurements of two sites on Spitsbergen, Barentsburg and Ny-Ålesund, in the European Arctic are presented and compared. We find slightly higher aerosol optical depths at Barentsburg and attribute this to a higher concentration of small particles.
Shi Kuang, Bo Wang, Michael J. Newchurch, Kevin Knupp, Paula Tucker, Edwin W. Eloranta, Joseph P. Garcia, Ilya Razenkov, John T. Sullivan, Timothy A. Berkoff, Guillaume Gronoff, Liqiao Lei, Christoph J. Senff, Andrew O. Langford, Thierry Leblanc, and Vijay Natraj
Atmos. Meas. Tech., 13, 5277–5292, https://doi.org/10.5194/amt-13-5277-2020, https://doi.org/10.5194/amt-13-5277-2020, 2020
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Ozone lidar is a state-of-the-art remote-sensing instrument to measure atmospheric ozone concentrations with high spatiotemporal resolution. In this study, we show that an ozone lidar can also provide reliable aerosol measurements through intercomparison with colocated aerosol lidar observations.
Laaziz El Amraoui, Bojan Sič, Andrea Piacentini, Virginie Marécal, Nicolas Frebourg, and Jean-Luc Attié
Atmos. Meas. Tech., 13, 4645–4667, https://doi.org/10.5194/amt-13-4645-2020, https://doi.org/10.5194/amt-13-4645-2020, 2020
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The aim of this paper is to present the assimilation of lidar observations from the CALIOP instrument onboard the CALIPSO satellite in the chemistry-transport model of Météo-France, MOCAGE. We presented the first results of the assimilation of the extinction coefficient observations of the CALIOP lidar instrument during the pre-ChArMEx-TRAQA field campaign. We evaluated the added value of the assimilation product to better document a desert dust transport event compared to the model free run.
Carl Malings, Daniel M. Westervelt, Aliaksei Hauryliuk, Albert A. Presto, Andrew Grieshop, Ashley Bittner, Matthias Beekmann, and R. Subramanian
Atmos. Meas. Tech., 13, 3873–3892, https://doi.org/10.5194/amt-13-3873-2020, https://doi.org/10.5194/amt-13-3873-2020, 2020
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Most air quality information comes from accurate but expensive instruments. These can be supplemented by lower-cost sensors to increase the density of ground data and expand monitoring into less well-instrumented areas, like sub-Saharan Africa. In this paper, we look at how low-cost sensor data can be combined with satellite information on air quality (which requires ground data to properly calibrate measurements) and assess the benefits these low-cost sensors provide in this context.
Zhong Chen, Pawan K. Bhartia, Omar Torres, Glen Jaross, Robert Loughman, Matthew DeLand, Peter Colarco, Robert Damadeo, and Ghassan Taha
Atmos. Meas. Tech., 13, 3471–3485, https://doi.org/10.5194/amt-13-3471-2020, https://doi.org/10.5194/amt-13-3471-2020, 2020
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The scope of the paper is the evaluation of stratospheric aerosols derived from the OMPS/LP instrument via comparison with independent datasets from the SAGE III/ISS instrument. Results show very good agreement for extinction profiles between an altitude of 19 and 27 km, to within ±25 %, and show systematic differences (LP-SAGE III/ISS) above 28 km and below 19 km (greater than ±25 %).
Steven Albers, Stephen M. Saleeby, Sonia Kreidenweis, Qijing Bian, Peng Xian, Zoltan Toth, Ravan Ahmadov, Eric James, and Steven D. Miller
Atmos. Meas. Tech., 13, 3235–3261, https://doi.org/10.5194/amt-13-3235-2020, https://doi.org/10.5194/amt-13-3235-2020, 2020
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A fast 3D visible-light forward operator is used to realistically visualize, validate, and potentially assimilate ground- and space-based camera and satellite imagery with NWP models. Three-dimensional fields of hydrometeors, aerosols, and 2D land surface variables are considered in the generation of radiance fields and RGB imagery from a variety of vantage points.
Swadhin Nanda, Martin de Graaf, J. Pepijn Veefkind, Maarten Sneep, Mark ter Linden, Jiyunting Sun, and Pieternel F. Levelt
Atmos. Meas. Tech., 13, 3043–3059, https://doi.org/10.5194/amt-13-3043-2020, https://doi.org/10.5194/amt-13-3043-2020, 2020
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This paper presents a first validation of the TROPOspheric Monitoring Instrument (TROPOMI) aerosol layer height (ALH) product, which is an estimate of the height of an aerosol layer using a spectrometer on board ESA's Sentinel-5 Precursor satellite mission. Comparison between the TROPOMI ALH product and co-located aerosol extinction heights from the CALIOP instrument on board NASA's CALIPSO mission show good agreement for selected cases over the ocean and large differences over land.
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Short summary
The aim of this work is to investigate the limitations of calculating long-term trends of a parameter that quantifies the overall effect of atmospheric aerosols on the solar radiation. A main finding is that even instruments with good agreement between their observations can show significantly different linear trends. By calculating time-varying trends, the trend agreement is shown to improve. We also show that different methods of trend estimation can result in significant trend differences.
The aim of this work is to investigate the limitations of calculating long-term trends of a...
