Articles | Volume 14, issue 8
19 Aug 2021
Research article | 19 Aug 2021
Real-time UV index retrieval in Europe using Earth observation-based techniques: system description and quality assessment
Panagiotis G. Kosmopoulos et al.
No articles found.
Leonie Bernet, Tove Svendby, Georg Hansen, Yvan Orsolini, Arne Dahlback, Florence Goutail, Andrea Pazmiño, Boyan Petkov, and Arve Kylling
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
After the severe destruction of the ozone layer, the amount of ozone in the stratosphere is expected to increase again. At northern high-latitudes, however, such a recovery has not been detected yet. To assess ozone changes in that region, we analyse the amount of ozone above specific locations (total ozone) measured at three stations in Norway. We found that total ozone increases significantly at two Arctic stations, which may be an indication for ozone recovery at northern high-latitudes.
Carmen González, José M. Vilaplana, José A. Bogeat, and Antonio Serrano
Atmos. Meas. Tech., 15, 4125–4133,Short summary
Monitoring ultraviolet (UV) radiation is important since it can have harmful effects on the biosphere. Array spectroradiometers are increasingly used to measure UV as they are more versatile than scanning spectroradiometers. In this study, the long-term performance of the BTS-2048-UV-S-WP array spectroradiometer was assessed. The results show that the BTS can reliably measure both the UV index and UV radiation in the 300–360 nm range. Moreover, the BTS was stable and showed no seasonal behavior.
Angelos Karanikolas, Natalia Kouremeti, Julian Gröbner, Luca Egli, and Stelios Kazadzis
Atmos. Meas. Tech. Discuss.,
Preprint under review for AMTShort 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 improves. We also show that different methods of trend estimation can result to significant trend differences.
Kostas Eleftheratos, John Kapsomenakis, Ilias Fountoulakis, Christos S. Zerefos, Patrick Jöckel, Martin Dameris, Alkiviadis F. Bais, Germar Bernhard, Dimitra Kouklaki, Kleareti Tourpali, Scott Stierle, J. Ben Liley, Colette Brogniez, Frédérique Auriol, Henri Diémoz, Stana Simic, and Irina Petropavlovskikh
Our study discusses the future evolution of the DNA-damaging UV-B radiation in view of climate change and the reduction of ozone depleting substances. It is presented that the DNA harmful UV-B radiation might increase after 2050 between 50° N–50° S mainly due to cloud changes associated with climate change, something that is likely not to happen at high latitudes, where the DNA active irradiance is projected to continue its downward trend after 2050 mainly due to the continued increase of ozone.
Peristera Paschou, Nikolaos Siomos, Alexandra Tsekeri, Alexandros Louridas, George Georgoussis, Volker Freudenthaler, Ioannis Binietoglou, George Tsaknakis, Alexandros Tavernarakis, Christos Evangelatos, Jonas von Bismarck, Thomas Kanitz, Charikleia Meleti, Eleni Marinou, and Vassilis Amiridis
Atmos. Meas. Tech., 15, 2299–2323,Short summary
The eVe lidar delivers quality-assured aerosol and cloud optical properties according to the standards of ACTRIS. It is a mobile reference system for the validation of the ESA's Aeolus satellite mission (L2 aerosol and cloud products). eVe provides linear and circular polarisation measurements with Raman capabilities. Here, we describe the system design, the polarisation calibration techniques, and the software for the retrieval of the optical products.
Luca Egli, Julian Gröbner, Gregor Hülsen, Herbert Schill, and René Stübi
Atmos. Meas. Tech., 15, 1917–1930,Short summary
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,Short summary
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.
Stephen M. Platt, Øystein Hov, Torunn Berg, Knut Breivik, Sabine Eckhardt, Konstantinos Eleftheriadis, Nikolaos Evangeliou, Markus Fiebig, Rebecca Fisher, Georg Hansen, Hans-Christen Hansson, Jost Heintzenberg, Ove Hermansen, Dominic Heslin-Rees, Kim Holmén, Stephen Hudson, Roland Kallenborn, Radovan Krejci, Terje Krognes, Steinar Larssen, David Lowry, Cathrine Lund Myhre, Chris Lunder, Euan Nisbet, Pernilla B. Nizzetto, Ki-Tae Park, Christina A. Pedersen, Katrine Aspmo Pfaffhuber, Thomas Röckmann, Norbert Schmidbauer, Sverre Solberg, Andreas Stohl, Johan Ström, Tove Svendby, Peter Tunved, Kjersti Tørnkvist, Carina van der Veen, Stergios Vratolis, Young Jun Yoon, Karl Espen Yttri, Paul Zieger, Wenche Aas, and Kjetil Tørseth
Atmos. Chem. Phys., 22, 3321–3369,Short summary
Here we detail the history of the Zeppelin Observatory, a unique global background site and one of only a few in the high Arctic. We present long-term time series of up to 30 years of atmospheric components and atmospheric transport phenomena. Many of these time series are important to our understanding of Arctic and global atmospheric composition change. Finally, we discuss the future of the Zeppelin Observatory and emerging areas of future research on the Arctic atmosphere.
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,Short summary
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.
Monica Campanelli, Henri Diémoz, Anna Maria Siani, Alcide di Sarra, Anna Maria Iannarelli, Rei Kudo, Gabriele Fasano, Giampietro Casasanta, Luca Tofful, Marco Cacciani, Paolo Sanò, and Stefano Dietrich
Atmos. Meas. Tech., 15, 1171–1183,Short summary
The aerosol optical depth (AOD) characteristics in an urban area of Rome were retrieved over a period of 11 years (2010–2020) to determine, for the first time, their effect on the incoming ultraviolet (UV) solar radiation. The surface forcing efficiency shows that the AOD is the primary parameter affecting the surface irradiance in Rome, and it is found to be greater for smaller zenith angles and for larger and more absorbing particles in the UV range (such as, e.g., mineral dust).
Ilias Fountoulakis, Henri Diémoz, Anna Maria Siani, Alcide di Sarra, Daniela Meloni, and Damiano M. Sferlazzo
Atmos. Chem. Phys., 21, 18689–18705,Short summary
The variability and trends of solar spectral UV irradiance have been studied for the periods 1996–2020 (for Rome) and 2006–2020 (for Lampedusa, Rome, and Aosta) with respect to the variability and trends of total ozone and geopotential height. Analyses revealed increasing UV in particular months at all sites, possibly due to decreasing lower-stratospheric ozone (at Rome in 1996–2020) and decreasing attenuation by aerosols and/or clouds (at all stations in 2006–2020).
Song Liu, Pieter Valks, Gaia Pinardi, Jian Xu, Ka Lok Chan, Athina Argyrouli, Ronny Lutz, Steffen Beirle, Ehsan Khorsandi, Frank Baier, Vincent Huijnen, Alkiviadis Bais, Sebastian Donner, Steffen Dörner, Myrto Gratsea, François Hendrick, Dimitris Karagkiozidis, Kezia Lange, Ankie J. M. Piters, Julia Remmers, Andreas Richter, Michel Van Roozendael, Thomas Wagner, Mark Wenig, and Diego G. Loyola
Atmos. Meas. Tech., 14, 7297–7327,Short summary
In this work, an improved tropospheric NO2 retrieval algorithm from TROPOMI measurements over Europe is presented. The stratospheric estimation is implemented with correction for the dependency of the stratospheric NO2 on the viewing geometry. The AMF calculation is implemented using improved surface albedo, a priori NO2 profiles, and cloud correction. The improved tropospheric NO2 data show good correlations with ground-based MAX-DOAS measurements.
Stavros-Andreas Logothetis, Vasileios Salamalikis, Antonis Gkikas, Stelios Kazadzis, Vassilis Amiridis, and Andreas Kazantzidis
Atmos. Chem. Phys., 21, 16499–16529,Short summary
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,Short summary
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.
Henri Diémoz, Anna Maria Siani, Stefano Casadio, Anna Maria Iannarelli, Giuseppe Rocco Casale, Vladimir Savastiouk, Alexander Cede, Martin Tiefengraber, and Moritz Müller
Earth Syst. Sci. Data, 13, 4929–4950,Short summary
A 20-year (1996–2017) record of nitrogen dioxide column densities collected in Rome by a Brewer spectrophotometer is presented, together with the novel algorithm employed to re-evaluate the series. The high quality of the data is demonstrated by comparison with reference instrumentation, including a co-located Pandora spectrometer. The data can be used for satellite validation and identification of NO2 trends. The method can be replicated on other instruments of the international Brewer network.
Alena Dekhtyareva, Mark Hermanson, Anna Nikulina, Ove Hermansen, Tove Svendby, Kim Holmén, and Rune Graversen
Atmos. Chem. Phys. Discuss.,
Revised manuscript under review for ACPShort summary
Despite decades of industrial activity in Svalbard, there is no continuous air pollution monitoring in the region’s settlements except Ny-Ålesund. The NOx and O3 observations from the three stations-network have been compared for the first time in this study. It has been shown how the large-scale weather regimes control the synoptic meteorological conditions and determine the atmospheric long-range transport pathways and efficiency of local air pollution dispersion.
Janusz W. Krzyścin, Bonawentura Rajewska-Więch, and Janusz Jarosławski
Earth Syst. Sci. Data, 13, 4425–4436,Short summary
The article presents a dataset comprising all manual observations of total column ozone taken at Belsk (Poland) from 23 March 1963 up to 31 December 2019 by the Dobson spectrophotometer. The dataset contains results of ~115 000 intraday measurements. The original data can be used for trend analyses as the instrument's aging has not been detected. For comparative research with other ozone data sources, correction procedures (for adjustments to the Brewer spectrophotometer output) are proposed.
Kevin Lamy, Thierry Portafaix, Colette Brogniez, Kaisa Lakkala, Mikko R. A. Pitkänen, Antti Arola, Jean-Baptiste Forestier, Vincent Amelie, Mohamed Abdoulwahab Toihir, and Solofoarisoa Rakotoniaina
Earth Syst. Sci. Data, 13, 4275–4301,Short summary
This paper is about the presentation of the UV-Indien measurement network. This network measures the ultraviolet radiation emitted by the Sun received at the Earth's surface and the clouding above each station. It has been deployed at several sites in the Indian Ocean region representing different environmental conditions. A description of the instruments and their calibration, maintenance, and data processing is presented in this paper along with a valuation of the data quality.
Isabelle De Smedt, Gaia Pinardi, Corinne Vigouroux, Steven Compernolle, Alkis Bais, Nuria Benavent, Folkert Boersma, Ka-Lok Chan, Sebastian Donner, Kai-Uwe Eichmann, Pascal Hedelt, François Hendrick, Hitoshi Irie, Vinod Kumar, Jean-Christopher Lambert, Bavo Langerock, Christophe Lerot, Cheng Liu, Diego Loyola, Ankie Piters, Andreas Richter, Claudia Rivera Cárdenas, Fabian Romahn, Robert George Ryan, Vinayak Sinha, Nicolas Theys, Jonas Vlietinck, Thomas Wagner, Ting Wang, Huan Yu, and Michel Van Roozendael
Atmos. Chem. Phys., 21, 12561–12593,Short summary
This paper assess the performances of the TROPOMI formaldehyde observations compared to its predecessor OMI at different spatial and temporal scales. We also use a global network of MAX-DOAS instruments to validate both satellite datasets for a large range of HCHO columns. The precision obtained with daily TROPOMI observations is comparable to monthly OMI observations. We present clear detection of weak HCHO column enhancements related to shipping emissions in the Indian Ocean.
Roeland Van Malderen, Dirk De Muer, Hugo De Backer, Deniz Poyraz, Willem W. Verstraeten, Veerle De Bock, Andy W. Delcloo, Alexander Mangold, Quentin Laffineur, Marc Allaart, Frans Fierens, and Valérie Thouret
Atmos. Chem. Phys., 21, 12385–12411,Short summary
The main aim of initiating measurements of the vertical distribution of the ozone concentration by means of ozonesondes attached to weather balloons at Uccle in 1969 was to improve weather forecasts. Since then, this measurement technique has barely changed, but the dense, long-term, and homogeneous Uccle dataset currently remains crucial for studying the temporal evolution of ozone from the surface to the stratosphere and is also the backbone of the validation of satellite ozone retrievals.
Antti Arola, William Wandji Nyamsi, Antti Lipponen, Stelios Kazadzis, Nickolay A. Krotkov, and Johanna Tamminen
Atmos. Meas. Tech., 14, 4947–4957,Short summary
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,Short summary
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.
Tove M. Svendby, Bjørn Johnsen, Arve Kylling, Arne Dahlback, Germar H. Bernhard, Georg H. Hansen, Boyan Petkov, and Vito Vitale
Atmos. Chem. Phys., 21, 7881–7899,Short summary
Measurements of total ozone and effective cloud transmittance (eCLT) have been performed since 1995 at three Norwegian sites with GUV multi-filter instruments. The unique data sets of high-time-resolution measurements can be used for a broad range of studies. Data analyses reveal an increase in total ozone above Norway from 1995 to 2019. Measurements of GUV eCLT indicate changes in albedo in Ny-Ålesund (Svalbard) during the past 25 years, most likely resulting from increased Arctic ice melt.
Marek Šmíd, Geiland Porrovecchio, Jiří Tesař, Tim Burnitt, Luca Egli, Julian Grőbner, Petr Linduška, and Martin Staněk
Atmos. Meas. Tech., 14, 3573–3582,Short summary
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 %.
Rei Kudo, Henri Diémoz, Victor Estellés, Monica Campanelli, Masahiro Momoi, Franco Marenco, Claire L. Ryder, Osamu Ijima, Akihiro Uchiyama, Kouichi Nakashima, Akihiro Yamazaki, Ryoji Nagasawa, Nozomu Ohkawara, and Haruma Ishida
Atmos. Meas. Tech., 14, 3395–3426,Short summary
A new method, Skyrad pack MRI version 2, was developed to retrieve aerosol physical and optical properties, water vapor, and ozone column concentrations from the sky radiometer, a filter radiometer deployed in the SKYNET international network. Our method showed good performance in a radiative closure study using surface solar irradiances from the Baseline Surface Radiation Network and a comparison using aircraft in situ measurements of Saharan dust events during the SAVEX-D 2015 campaign.
Julian Gröbner, Herbert Schill, Luca Egli, and René Stübi
Atmos. Meas. Tech., 14, 3319–3331,Short summary
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.
Verena Schenzinger and Axel Kreuter
Atmos. Meas. Tech., 14, 2787–2798,Short summary
When measuring the aerosol optical depth of the atmosphere, clouds in front of the sun lead to erroneously high values. Therefore, measurements that are potentially affected by clouds need to be removed from the dataset by an automatic process. As the currently used algorithm cannot reliably identify thin clouds, we developed a new one based on a method borrowed from machine learning. Tests with 10 years of data show improved performance of the new routine and therefore higher data quality.
Ioanna Skoulidou, Maria-Elissavet Koukouli, Astrid Manders, Arjo Segers, Dimitris Karagkiozidis, Myrto Gratsea, Dimitris Balis, Alkiviadis Bais, Evangelos Gerasopoulos, Trisevgeni Stavrakou, Jos van Geffen, Henk Eskes, and Andreas Richter
Atmos. Chem. Phys., 21, 5269–5288,Short summary
The performance of LOTOS-EUROS v2.2.001 regional chemical transport model NO2 simulations is investigated over Greece from June to December 2018. Comparison with in situ NO2 measurements shows a spatial correlation coefficient of 0.86, while the model underestimates the concentrations mostly during daytime (12 to 15:00 local time). Further, the simulated tropospheric NO2 columns are evaluated against ground-based MAX-DOAS NO2 measurements and S5P/TROPOMI observations for July and December 2018.
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,
Tijl Verhoelst, Steven Compernolle, Gaia Pinardi, Jean-Christopher Lambert, Henk J. Eskes, Kai-Uwe Eichmann, Ann Mari Fjæraa, José Granville, Sander Niemeijer, Alexander Cede, Martin Tiefengraber, François Hendrick, Andrea Pazmiño, Alkiviadis Bais, Ariane Bazureau, K. Folkert Boersma, Kristof Bognar, Angelika Dehn, Sebastian Donner, Aleksandr Elokhov, Manuel Gebetsberger, Florence Goutail, Michel Grutter de la Mora, Aleksandr Gruzdev, Myrto Gratsea, Georg H. Hansen, Hitoshi Irie, Nis Jepsen, Yugo Kanaya, Dimitris Karagkiozidis, Rigel Kivi, Karin Kreher, Pieternel F. Levelt, Cheng Liu, Moritz Müller, Monica Navarro Comas, Ankie J. M. Piters, Jean-Pierre Pommereau, Thierry Portafaix, Cristina Prados-Roman, Olga Puentedura, Richard Querel, Julia Remmers, Andreas Richter, John Rimmer, Claudia Rivera Cárdenas, Lidia Saavedra de Miguel, Valery P. Sinyakov, Wolfgang Stremme, Kimberly Strong, Michel Van Roozendael, J. Pepijn Veefkind, Thomas Wagner, Folkard Wittrock, Margarita Yela González, and Claus Zehner
Atmos. Meas. Tech., 14, 481–510,Short summary
This paper reports on the ground-based validation of the NO2 data produced operationally by the TROPOMI instrument on board the Sentinel-5 Precursor satellite. Tropospheric, stratospheric, and total NO2 columns are compared to measurements collected from MAX-DOAS, ZSL-DOAS, and PGN/Pandora instruments respectively. The products are found to satisfy mission requirements in general, though negative mean differences are found at sites with high pollution levels. Potential causes are discussed.
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,Short summary
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.
Jan-Lukas Tirpitz, Udo Frieß, François Hendrick, Carlos Alberti, Marc Allaart, Arnoud Apituley, Alkis Bais, Steffen Beirle, Stijn Berkhout, Kristof Bognar, Tim Bösch, Ilya Bruchkouski, Alexander Cede, Ka Lok Chan, Mirjam den Hoed, Sebastian Donner, Theano Drosoglou, Caroline Fayt, Martina M. Friedrich, Arnoud Frumau, Lou Gast, Clio Gielen, Laura Gomez-Martín, Nan Hao, Arjan Hensen, Bas Henzing, Christian Hermans, Junli Jin, Karin Kreher, Jonas Kuhn, Johannes Lampel, Ang Li, Cheng Liu, Haoran Liu, Jianzhong Ma, Alexis Merlaud, Enno Peters, Gaia Pinardi, Ankie Piters, Ulrich Platt, Olga Puentedura, Andreas Richter, Stefan Schmitt, Elena Spinei, Deborah Stein Zweers, Kimberly Strong, Daan Swart, Frederik Tack, Martin Tiefengraber, René van der Hoff, Michel van Roozendael, Tim Vlemmix, Jan Vonk, Thomas Wagner, Yang Wang, Zhuoru Wang, Mark Wenig, Matthias Wiegner, Folkard Wittrock, Pinhua Xie, Chengzhi Xing, Jin Xu, Margarita Yela, Chengxin Zhang, and Xiaoyi Zhao
Atmos. Meas. Tech., 14, 1–35,Short summary
Multi-axis differential optical absorption spectroscopy (MAX-DOAS) is a ground-based remote sensing measurement technique that derives atmospheric aerosol and trace gas vertical profiles from skylight spectra. In this study, consistency and reliability of MAX-DOAS profiles are assessed by applying nine different evaluation algorithms to spectral data recorded during an intercomparison campaign in the Netherlands and by comparing the results to colocated supporting observations.
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,Short summary
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,Short summary
We validate several GOME-2 and OMI tropospheric NO2 products with 23 MAX-DOAS and 16 direct sun instruments distributed worldwide, highlighting large horizontal inhomogeneities at several sites affecting the validation results. We propose a method for quantification and correction. We show the application of such correction reduces the satellite underestimation in almost all heterogeneous cases, but a negative bias remains over the MAX-DOAS and direct sun network ensemble for both satellites.
Ilias Fountoulakis, Henri Diémoz, Anna Maria Siani, Gregor Hülsen, and Julian Gröbner
Earth Syst. Sci. Data, 12, 2787–2810,Short summary
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.
Yang Wang, Arnoud Apituley, Alkiviadis Bais, Steffen Beirle, Nuria Benavent, Alexander Borovski, Ilya Bruchkouski, Ka Lok Chan, Sebastian Donner, Theano Drosoglou, Henning Finkenzeller, Martina M. Friedrich, Udo Frieß, David Garcia-Nieto, Laura Gómez-Martín, François Hendrick, Andreas Hilboll, Junli Jin, Paul Johnston, Theodore K. Koenig, Karin Kreher, Vinod Kumar, Aleksandra Kyuberis, Johannes Lampel, Cheng Liu, Haoran Liu, Jianzhong Ma, Oleg L. Polyansky, Oleg Postylyakov, Richard Querel, Alfonso Saiz-Lopez, Stefan Schmitt, Xin Tian, Jan-Lukas Tirpitz, Michel Van Roozendael, Rainer Volkamer, Zhuoru Wang, Pinhua Xie, Chengzhi Xing, Jin Xu, Margarita Yela, Chengxin Zhang, and Thomas Wagner
Atmos. Meas. Tech., 13, 5087–5116,
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,Short summary
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.
Steven Compernolle, Tijl Verhoelst, Gaia Pinardi, José Granville, Daan Hubert, Arno Keppens, Sander Niemeijer, Bruno Rino, Alkis Bais, Steffen Beirle, Folkert Boersma, John P. Burrows, Isabelle De Smedt, Henk Eskes, Florence Goutail, François Hendrick, Alba Lorente, Andrea Pazmino, Ankie Piters, Enno Peters, Jean-Pierre Pommereau, Julia Remmers, Andreas Richter, Jos van Geffen, Michel Van Roozendael, Thomas Wagner, and Jean-Christopher Lambert
Atmos. Chem. Phys., 20, 8017–8045,Short summary
Tropospheric and stratospheric NO2 columns from the OMI QA4ECV NO2 satellite product are validated by comparison with ground-based measurements at 11 sites. The OMI stratospheric column has a small negative bias, and the OMI tropospheric column has a stronger negative bias relative to the ground-based data. Discrepancies are attributed to comparison errors (e.g. difference in horizontal smoothing) and measurement errors (e.g. clouds, aerosols, vertical smoothing and a priori proﬁle assumptions).
Margit Aun, Kaisa Lakkala, Ricardo Sanchez, Eija Asmi, Fernando Nollas, Outi Meinander, Larisa Sogacheva, Veerle De Bock, Antti Arola, Gerrit de Leeuw, Veijo Aaltonen, David Bolsée, Klara Cizkova, Alexander Mangold, Ladislav Metelka, Erko Jakobson, Tove Svendby, Didier Gillotay, and Bert Van Opstal
Atmos. Chem. Phys., 20, 6037–6054,Short summary
In 2017, new measurements of UV radiation started in Marambio, Antarctica, by the Finnish Meteorological Institute in collaboration with the Argentinian Servicio Meteorológico Nacional. The paper presents the results of UV irradiance measurements from March 2017 to March 2019, and it compares them with those from 2000–2008 and also with UV measurements at other Antarctic stations. In 2017/2018, below average UV radiation levels were recorded due to favourable ozone and cloud conditions.
Karin Kreher, Michel Van Roozendael, Francois Hendrick, Arnoud Apituley, Ermioni Dimitropoulou, Udo Frieß, Andreas Richter, Thomas Wagner, Johannes Lampel, Nader Abuhassan, Li Ang, Monica Anguas, Alkis Bais, Nuria Benavent, Tim Bösch, Kristof Bognar, Alexander Borovski, Ilya Bruchkouski, Alexander Cede, Ka Lok Chan, Sebastian Donner, Theano Drosoglou, Caroline Fayt, Henning Finkenzeller, David Garcia-Nieto, Clio Gielen, Laura Gómez-Martín, Nan Hao, Bas Henzing, Jay R. Herman, Christian Hermans, Syedul Hoque, Hitoshi Irie, Junli Jin, Paul Johnston, Junaid Khayyam Butt, Fahim Khokhar, Theodore K. Koenig, Jonas Kuhn, Vinod Kumar, Cheng Liu, Jianzhong Ma, Alexis Merlaud, Abhishek K. Mishra, Moritz Müller, Monica Navarro-Comas, Mareike Ostendorf, Andrea Pazmino, Enno Peters, Gaia Pinardi, Manuel Pinharanda, Ankie Piters, Ulrich Platt, Oleg Postylyakov, Cristina Prados-Roman, Olga Puentedura, Richard Querel, Alfonso Saiz-Lopez, Anja Schönhardt, Stefan F. Schreier, André Seyler, Vinayak Sinha, Elena Spinei, Kimberly Strong, Frederik Tack, Xin Tian, Martin Tiefengraber, Jan-Lukas Tirpitz, Jeroen van Gent, Rainer Volkamer, Mihalis Vrekoussis, Shanshan Wang, Zhuoru Wang, Mark Wenig, Folkard Wittrock, Pinhua H. Xie, Jin Xu, Margarita Yela, Chengxin Zhang, and Xiaoyi Zhao
Atmos. Meas. Tech., 13, 2169–2208,Short summary
In September 2016, 36 spectrometers from 24 institutes measured a number of key atmospheric pollutants during an instrument intercomparison campaign (CINDI-2) at Cabauw, the Netherlands. Here we report on the outcome of this intercomparison exercise. The three major goals were to characterise the differences between the participating instruments, to define a robust methodology for performance assessment, and to contribute to the harmonisation of the measurement settings and retrieval methods.
Kaisa Lakkala, Margit Aun, Ricardo Sanchez, Germar Bernhard, Eija Asmi, Outi Meinander, Fernando Nollas, Gregor Hülsen, Tomi Karppinen, Veijo Aaltonen, Antti Arola, and Gerrit de Leeuw
Earth Syst. Sci. Data, 12, 947–960,Short summary
A GUV multi-filter radiometer was set up at Marambio, 64° S, 56° W, Antarctica, in 2017. The instrument continuously measures ultraviolet (UV) radiation, visible (VIS) radiation and photosynthetically active radiation (PAR). The measurements are designed for providing high-quality long-term time series that can be used to assess the impact of global climate change in the Antarctic region. The data from the last 5 d are plotted and updated daily.
Christine Aebi, Julian Gröbner, Stelios Kazadzis, Laurent Vuilleumier, Antonis Gkikas, and Niklaus Kämpfer
Atmos. Meas. Tech., 13, 907–923,Short summary
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.
Sebastian Donner, Jonas Kuhn, Michel Van Roozendael, Alkiviadis Bais, Steffen Beirle, Tim Bösch, Kristof Bognar, Ilya Bruchkouski, Ka Lok Chan, Steffen Dörner, Theano Drosoglou, Caroline Fayt, Udo Frieß, François Hendrick, Christian Hermans, Junli Jin, Ang Li, Jianzhong Ma, Enno Peters, Gaia Pinardi, Andreas Richter, Stefan F. Schreier, André Seyler, Kimberly Strong, Jan-Lukas Tirpitz, Yang Wang, Pinhua Xie, Jin Xu, Xiaoyi Zhao, and Thomas Wagner
Atmos. Meas. Tech., 13, 685–712,Short summary
The calibration of the elevation angles of MAX-DOAS instruments is important for the correct interpretation of such MAX-DOAS measurements. We present and evaluate different methods for the elevation calibration of MAX-DOAS instruments which were applied during the CINDI-2 field campaign.
Stephan Nyeki, Stefan Wacker, Christine Aebi, Julian Gröbner, Giovanni Martucci, and Laurent Vuilleumier
Atmos. Chem. Phys., 19, 13227–13241,Short summary
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.
Katerina Garane, Maria-Elissavet Koukouli, Tijl Verhoelst, Christophe Lerot, Klaus-Peter Heue, Vitali Fioletov, Dimitrios Balis, Alkiviadis Bais, Ariane Bazureau, Angelika Dehn, Florence Goutail, Jose Granville, Debora Griffin, Daan Hubert, Arno Keppens, Jean-Christopher Lambert, Diego Loyola, Chris McLinden, Andrea Pazmino, Jean-Pierre Pommereau, Alberto Redondas, Fabian Romahn, Pieter Valks, Michel Van Roozendael, Jian Xu, Claus Zehner, Christos Zerefos, and Walter Zimmer
Atmos. Meas. Tech., 12, 5263–5287,Short summary
The Sentinel-5 Precursor TROPOMI near real time (NRTI) and offline (OFFL) total ozone column (TOC) products are validated against direct-sun and twilight zenith-sky ground-based TOC measurements and other already known spaceborne sensors. The results show that the TROPOMI TOC measurements are in very good agreement with the ground-based measurements and satellite sensor measurements and that they are well within the product requirements.
Henri Diémoz, Gian Paolo Gobbi, Tiziana Magri, Giordano Pession, Sara Pittavino, Ivan K. F. Tombolato, Monica Campanelli, and Francesca Barnaba
Atmos. Chem. Phys., 19, 10129–10160,Short summary
In a companion paper, we investigated airmass exchanges from the Po plain to the Alps through detailed case studies. Here (part 2) we use 3 years of multi-sensor observations and models to quantify the long-term impact of transport on air quality (>25% on PM10) and aerosol physico-chemical characteristics. We quantify the frequency of occurrence (up to 70% of days) in relation to meteorology (wind flows). We also show how the experimental results can improve air-quality forecasting capabilities.
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,Short summary
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.
Klaus Gierens and Kostas Eleftheratos
Atmos. Chem. Phys., 19, 3733–3746,Short summary
We derive a new method to retrieve upper-tropospheric humidity (UTH) from High-resolution Infrared Radiation Sounder (HIRS) channel 12 brightness temperatures. With the new method we solve an old problem, namely that the wavelength change that occurred between HIRS 2 on NOAA 14 and HIRS 3 on NOAA 15 led to the retrieval of many more events with high UTH; that is, the time series shows strong jumps at high UTH values. This old problem is solved with the new retrieval.
Henri Diémoz, Francesca Barnaba, Tiziana Magri, Giordano Pession, Davide Dionisi, Sara Pittavino, Ivan K. F. Tombolato, Monica Campanelli, Lara Sofia Della Ceca, Maxime Hervo, Luca Di Liberto, Luca Ferrero, and Gian Paolo Gobbi
Atmos. Chem. Phys., 19, 3065–3095,Short summary
We assess the impact of air masses transported from the Po basin on the particulate matter (PM) levels in the northwestern Alps using multi-sensor observations from ground and space, and models. In this part 1 of the study, we investigate the phenomenon through three selected case studies representative of different seasons. We show that advected aerosols remarkably degrade the air quality of the Alpine area (PM10 increasing up to >100 µg m−3) and we discuss the measurement–model discrepancies.
Kostas Eleftheratos, Christos S. Zerefos, Dimitris S. Balis, Maria-Elissavet Koukouli, John Kapsomenakis, Diego G. Loyola, Pieter Valks, Melanie Coldewey-Egbers, Christophe Lerot, Stacey M. Frith, Amund S. Haslerud, Ivar S. A. Isaksen, and Seppo Hassinen
Atmos. Meas. Tech., 12, 987–1011,Short summary
We examine the ability of GOME-2A total ozone data to capture variability related to known natural oscillations, such as the QBO, ENSO and NAO, with respect to other satellite datasets, ground-based data, and chemical transport model simulations. The analysis is based on the GOME-2 satellite total ozone columns for the period 2007–2016 which form part of the operational EUMETSAT AC SAF GOME-2 MetOp A GDP4.8 latest data product.
Silas Michaelides and Charalampos Kontoes
Adv. Geosci., 47, 17–19,
Stephen M. Platt, Sabine Eckhardt, Benedicte Ferré, Rebecca E. Fisher, Ove Hermansen, Pär Jansson, David Lowry, Euan G. Nisbet, Ignacio Pisso, Norbert Schmidbauer, Anna Silyakova, Andreas Stohl, Tove M. Svendby, Sunil Vadakkepuliyambatta, Jürgen Mienert, and Cathrine Lund Myhre
Atmos. Chem. Phys., 18, 17207–17224,Short summary
We measured atmospheric mixing ratios of methane over the Arctic Ocean around Svalbard and compared observed variations to inventories for anthropogenic, wetland, and biomass burning methane emissions and an atmospheric transport model. With knowledge of where variations were expected due to the aforementioned land-based emissions, we were able to identify and quantify a methane source from the ocean north of Svalbard, likely from sub-sea hydrocarbon seeps and/or gas hydrate decomposition.
Kaisa Lakkala, Alberto Redondas, Outi Meinander, Laura Thölix, Britta Hamari, Antonio Fernando Almansa, Virgilio Carreno, Rosa Delia García, Carlos Torres, Guillermo Deferrari, Hector Ochoa, Germar Bernhard, Ricardo Sanchez, and Gerrit de Leeuw
Atmos. Chem. Phys., 18, 16019–16031,Short summary
Solar UV irradiances were measured at Ushuaia (54° S) and Marambio (64° S) during 2000–2013. The measurements were part of the Antarctic NILU-UV network, which was maintained as a cooperation between Spain, Argentina and Finland. The time series of the network were analysed for the first time in this study. At both stations maximum UV indices and daily doses were measured when spring-time ozone loss episodes occurred. The maximum UV index was 13 and 12 in Ushuaia and Marambio, respectively.
Davide Dionisi, Francesca Barnaba, Henri Diémoz, Luca Di Liberto, and Gian Paolo Gobbi
Atmos. Meas. Tech., 11, 6013–6042,
Christine Aebi, Julian Gröbner, and Niklaus Kämpfer
Atmos. Meas. Tech., 11, 5549–5563,Short summary
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,Short summary
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,Short summary
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.
Michael Priestley, Michael le Breton, Thomas J. Bannan, Stephen D. Worrall, Asan Bacak, Andrew R. D. Smedley, Ernesto Reyes-Villegas, Archit Mehra, James Allan, Ann R. Webb, Dudley E. Shallcross, Hugh Coe, and Carl J. Percival
Atmos. Chem. Phys., 18, 13481–13493,
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,Short summary
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.
Anna Maria Siani, Francesca Frasca, Francesco Scarlatti, Arianna Religi, Henri Diémoz, Giuseppe R. Casale, Massimiliano Pedone, and Volodya Savastiouk
Atmos. Meas. Tech., 11, 5105–5123,Short summary
Total ozone columns (TOCs) measured by Brewer spectrophotometers located at Rome and Aosta (Italy) were calculated using different processing software packages, and the differences in the TOC retrievals are investigated. Large differences in TOC retrievals can be experienced when the instrumental sensitivity exhibits a long-term drift. The variability in TOC retrievals depends on the algorithm for calculating the standard lamp correction.
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,Short summary
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.
John S. Rimmer, Alberto Redondas, and Tomi Karppinen
Atmos. Chem. Phys., 18, 10347–10353,Short summary
The Vienna Convention to Protect the Ozone Layer was signed in 1985 to promote research and information exchange on the science of ozone depletion including monitoring of total ozone column and spectrally resolved solar ultraviolet radiation. This is a global challenge and, as such, all efforts to gather data should be consistent. This work has resulted in a framework for all Brewer Ozone spectrophotometers to provide data in a consistent way in terms of calibration and quality assurance.
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,Short summary
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,Short summary
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,Short summary
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 %).
Alberto Berjón, Alberto Redondas, Meelis-Mait Sildoja, Saulius Nevas, Keith Wilson, Sergio F. León-Luis, Omar el Gawhary, and Ilias Fountoulakis
Atmos. Meas. Tech., 11, 3323–3337,Short summary
The Brewer spectrophotometer has been used for decades as reference instrument to retrieve total ozone column (TOC) and for validation of satellite based measurements. This spectrophotometer has a thermal sensitivity already known, which is usually characterized using two different retrieval procedures. In this work, we report on a comparative study of the temperature coefficients retrieval procedures, obtaining differences less that 0.08 % in TOC when using any of the procedures.
Christos Zerefos, John Kapsomenakis, Kostas Eleftheratos, Kleareti Tourpali, Irina Petropavlovskikh, Daan Hubert, Sophie Godin-Beekmann, Wolfgang Steinbrecht, Stacey Frith, Viktoria Sofieva, and Birgit Hassler
Atmos. Chem. Phys., 18, 6427–6440,Short summary
We point out the representativeness of single lidar stations for zonally averaged ozone profile variations in the middle/upper stratosphere. We examine the contribution of chemistry and natural proxies to ozone profile trends. Above 10 hPa an “inflection point” between 1997–99 marks the end of significant negative ozone trends, followed by a recent period of positive ozone change in 1998–2015. Below 15 hPa the pre-1998 negative ozone trends tend to become insignificant as we move to 2015.
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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.
Anders V. Lindfors, Jukka Kujanpää, Niilo Kalakoski, Anu Heikkilä, Kaisa Lakkala, Tero Mielonen, Maarten Sneep, Nickolay A. Krotkov, Antti Arola, and Johanna Tamminen
Atmos. Meas. Tech., 11, 997–1008,Short summary
This paper describes the algorithm that will be used for estimating surface UV radiation from TROPOMI (TROPOspheric Monitoring Instrument) measurements. TROPOMI is the only payload of the Sentinel-5 Precursor (S5P), which is a polar-orbiting satellite mission of the European Space Agency (ESA). The presented algorithm has been tested using input based on previous satellite measurements. These preliminary results indicate that the algorithm is functioning according to expectations.
Klaus Gierens, Kostas Eleftheratos, and Robert Sausen
Atmos. Meas. Tech., 11, 939–948,Short summary
HIRS channel 12 on the series of NOAA weathersatellites is sensitive to humidity in the upper troposphere. A change in its central wavelength between NOAA 14 and 15 made it necessary to perform an intercalibration to retain a homogeneous time series. Here we show that the intercalibration of Shi and Bates (2011), which is based on statistical methods, can be underpinned by physical arguments using results of radiative transfer calculations.
Panagiotis G. Kosmopoulos, Stelios Kazadzis, Michael Taylor, Panagiotis I. Raptis, Iphigenia Keramitsoglou, Chris Kiranoudis, and Alkiviadis F. Bais
Atmos. Meas. Tech., 11, 907–924,Short summary
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,Short summary
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,Short summary
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.
Monica Campanelli, Alessandra Mascitelli, Paolo Sanò, Henri Diémoz, Victor Estellés, Stefano Federico, Anna Maria Iannarelli, Francesca Fratarcangeli, Augusto Mazzoni, Eugenio Realini, Mattia Crespi, Olivier Bock, Jose A. Martínez-Lozano, and Stefano Dietrich
Atmos. Meas. Tech., 11, 81–94,Short summary
The estimation of precipitable water vapour (W) content is of great interest in both meteorological and climatological studies. Sun photometers allowed the development of W automatic estimations with high temporal resolution. A new methodology, based on the hypothesis that the calibration parameters characterizing the atmospheric transmittance are dependent on vertical profiles of temperature, air pressure and moisture typical of each measurement site, has been presented providing good results.
Alexandra Tsekeri, Anton Lopatin, Vassilis Amiridis, Eleni Marinou, Julia Igloffstein, Nikolaos Siomos, Stavros Solomos, Panagiotis Kokkalis, Ronny Engelmann, Holger Baars, Myrto Gratsea, Panagiotis I. Raptis, Ioannis Binietoglou, Nikolaos Mihalopoulos, Nikolaos Kalivitis, Giorgos Kouvarakis, Nikolaos Bartsotas, George Kallos, Sara Basart, Dirk Schuettemeyer, Ulla Wandinger, Albert Ansmann, Anatoli P. Chaikovsky, and Oleg Dubovik
Atmos. Meas. Tech., 10, 4995–5016,Short summary
The Generalized Aerosol Retrieval from Radiometer and Lidar Combined data algorithm (GARRLiC) and the LIdar-Radiometer Inversion Code (LIRIC) provide the opportunity to study the aerosol vertical distribution by combining ground-based lidar and sun-photometric measurements. Here, we utilize the capabilities of both algorithms for the characterization of Saharan dust and marine particles, along with their mixtures, in the south-eastern Mediterranean.
William Wandji Nyamsi, Mikko R. A. Pitkänen, Youva Aoun, Philippe Blanc, Anu Heikkilä, Kaisa Lakkala, Germar Bernhard, Tapani Koskela, Anders V. Lindfors, Antti Arola, and Lucien Wald
Atmos. Meas. Tech., 10, 4965–4978,Short summary
This paper proposes a new, fast and accurate method for estimating UV fluxes at ground level in cloud-free conditions at any place and time. The method performs very well with the Copernicus Atmosphere Monitoring Service products as inputs describing the state of the atmosphere. An accuracy that is close to the uncertainty of the measurements themselves is reached. We believe that our research will be widely used in the near future.
Andrew R. D. Smedley, John S. Rimmer, and Ann R. Webb
Atmos. Meas. Tech., 10, 4697–4704,Short summary
Long-term trends of total column ozone and assessments of its recovery are underpinned by daily “best representative values” from Brewer spectrophotometers and other ground-based instruments. However, the current calculation of these best representative values often rejects otherwise useful data and has deficiencies during partly cloudy days. We propose a new methodology that takes into account all valid data and accounts for unevenly spaced observations and their uncertainties.
Axel Kreuter, Mario Blumthaler, Martin Tiefengraber, Richard Kift, and Ann R. Webb
Atmos. Chem. Phys., 17, 14353–14364,Short summary
We have done measurements of the sky's brightness at the Italian coast and show the influence of the underlying surface: looking towards the land, the sky can be up to 50 % brighter than opposite viewing directions towards the ocean as a result of higher land reflectivity. At low solar elevations, the specular reflection from the ocean, or sun glint, increases the zenith brightness. Understanding these effects requires a 3-D model and is important when retrieving, e.g., aerosol properties.
Christine Aebi, Julian Gröbner, Niklaus Kämpfer, and Laurent Vuilleumier
Atmos. Meas. Tech., 10, 4587–4600,Short summary
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.
Ilias Fountoulakis, Alberto Redondas, Kaisa Lakkala, Alberto Berjon, Alkiviadis F. Bais, Lionel Doppler, Uwe Feister, Anu Heikkila, Tomi Karppinen, Juha M. Karhu, Tapani Koskela, Katerina Garane, Konstantinos Fragkos, and Volodya Savastiouk
Atmos. Meas. Tech., 10, 4491–4505,Short summary
Results of the temperature characterization of the global UV spectral measurements of eight different Brewer spectrophotometers operating in Greece, Finland, Germany and Spain are presented. Different temperature characterization methods are evaluated and an improved methodology for the correction of the measurements for the effects of temperature is presented.
René Stübi, Herbert Schill, Jörg Klausen, Laurent Vuilleumier, Julian Gröbner, Luca Egli, and Dominique Ruffieux
Atmos. Meas. Tech., 10, 4479–4490,Short summary
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,Short summary
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,Short summary
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.
Guanyu Huang, Xiong Liu, Kelly Chance, Kai Yang, Pawan K. Bhartia, Zhaonan Cai, Marc Allaart, Gérard Ancellet, Bertrand Calpini, Gerrie J. R. Coetzee, Emilio Cuevas-Agulló, Manuel Cupeiro, Hugo De Backer, Manvendra K. Dubey, Henry E. Fuelberg, Masatomo Fujiwara, Sophie Godin-Beekmann, Tristan J. Hall, Bryan Johnson, Everette Joseph, Rigel Kivi, Bogumil Kois, Ninong Komala, Gert König-Langlo, Giovanni Laneve, Thierry Leblanc, Marion Marchand, Kenneth R. Minschwaner, Gary Morris, Michael J. Newchurch, Shin-Ya Ogino, Nozomu Ohkawara, Ankie J. M. Piters, Françoise Posny, Richard Querel, Rinus Scheele, Frank J. Schmidlin, Russell C. Schnell, Otto Schrems, Henry Selkirk, Masato Shiotani, Pavla Skrivánková, René Stübi, Ghassan Taha, David W. Tarasick, Anne M. Thompson, Valérie Thouret, Matthew B. Tully, Roeland Van Malderen, Holger Vömel, Peter von der Gathen, Jacquelyn C. Witte, and Margarita Yela
Atmos. Meas. Tech., 10, 2455–2475,Short summary
It is essential to understand the data quality of +10-year OMI ozone product and impacts of the “row anomaly” (RA). We validate the OMI Ozone Profile (PROFOZ) product from Oct 2004 to Dec 2014 against ozonesonde observations globally. Generally, OMI has good agreement with ozonesondes. The spatiotemporal variation of retrieval performance suggests the need to improve OMI’s radiometric calibration especially during the post-RA period to maintain the long-term stability.
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,Short summary
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.
Stefano Federico, Rosa Claudia Torcasio, Paolo Sanò, Daniele Casella, Monica Campanelli, Jan Fokke Meirink, Ping Wang, Stefania Vergari, Henri Diémoz, and Stefano Dietrich
Atmos. Meas. Tech., 10, 2337–2352,Short summary
In this paper we evaluate the performance of two estimates of the global horizontal irradiance (GHI), one derived from the Meteosat Second Generation and one from a meteorological model (Regional Atmospheric Modeling System) forecast. The focus area is Italy, and the performance is evaluated for 12 pyranometers spanning a range of climate conditions, from Mediterranean maritime to Alpine.
Melina-Maria Zempila, Jos H. G. M. van Geffen, Michael Taylor, Ilias Fountoulakis, Maria-Elissavet Koukouli, Michiel van Weele, Ronald J. van der A, Alkiviadis Bais, Charikleia Meleti, and Dimitrios Balis
Atmos. Chem. Phys., 17, 7157–7174,Short summary
NILU irradiances at five UV channels were used to produce CIE, vitamin D, and DNA- damage daily doses via a neural network (NN) model. The NN was trained with collocated weighted Brewer spectra and uncertainty in the NILU-derived UV effective doses was 7.5 %. TEMIS UV products were found to be ~ 12.5 % higher than the NILU estimates. The results improve for cloud-free days with differences of 0.57 % for CIE, 1.22 % for vitamin D, and 1.18 % for DNA damage, with standard deviations of ~ 11–13 %.
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,Short summary
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.
Enno Peters, Gaia Pinardi, André Seyler, Andreas Richter, Folkard Wittrock, Tim Bösch, Michel Van Roozendael, François Hendrick, Theano Drosoglou, Alkiviadis F. Bais, Yugo Kanaya, Xiaoyi Zhao, Kimberly Strong, Johannes Lampel, Rainer Volkamer, Theodore Koenig, Ivan Ortega, Olga Puentedura, Mónica Navarro-Comas, Laura Gómez, Margarita Yela González, Ankie Piters, Julia Remmers, Yang Wang, Thomas Wagner, Shanshan Wang, Alfonso Saiz-Lopez, David García-Nieto, Carlos A. Cuevas, Nuria Benavent, Richard Querel, Paul Johnston, Oleg Postylyakov, Alexander Borovski, Alexander Elokhov, Ilya Bruchkouski, Haoran Liu, Cheng Liu, Qianqian Hong, Claudia Rivera, Michel Grutter, Wolfgang Stremme, M. Fahim Khokhar, Junaid Khayyam, and John P. Burrows
Atmos. Meas. Tech., 10, 955–978,Short summary
This work is about harmonization of differential optical absorption spectroscopy retrieval codes, which is a remote sensing technique widely used to derive atmospheric trace gas amounts. The study is based on ground-based measurements performed during the Multi-Axis DOAS Comparison campaign for Aerosols and Trace gases (MAD-CAT) in Mainz, Germany, in summer 2013. In total, 17 international groups working in the field of the DOAS technique participated in this study.
Thomas Carlund, Natalia Kouremeti, Stelios Kazadzis, and Julian Gröbner
Atmos. Meas. Tech., 10, 905–923,Short summary
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.
Klaus Gierens and Kostas Eleftheratos
Atmos. Meas. Tech., 10, 681–693,Short summary
For studies of trends in ice supersaturation in the upper troposphere we need very long time series of upper tropospheric humidity. The set of HIRS channel 12 satellite data can be used for this purpose, since Shi and Bates (2011) had provided an intercalibrated time series of channel 12 brightness temperatures. In the current paper we improve the intercalibration at the low tail of brightness temperatures, which leads to a more homogeneous time series of upper-tropospheric humidities.
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,Short summary
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,Short summary
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.
Anu Heikkilä, Jakke Sakari Mäkelä, Kaisa Lakkala, Outi Meinander, Jussi Kaurola, Tapani Koskela, Juha Matti Karhu, Tomi Karppinen, Esko Kyrö, and Gerrit de Leeuw
Geosci. Instrum. Method. Data Syst., 5, 531–540,Short summary
Lamp measurements used for the UV irradiance calibration of two Brewer spectrophotometers operated for 20 years in Jokioinen and Sodankylä, Finland, were examined. Temporal development of the responsivity after fixing the irradiance measurements into a specific scale was studied. Both long-term gradual decrease and abrupt changes in responsiveness were detected. Frequent-enough measurements of working standard lamps were found necessary to detect the short-term variations in responsiveness.
Martial Haeffelin, Quentin Laffineur, Juan-Antonio Bravo-Aranda, Marc-Antoine Drouin, Juan-Andrés Casquero-Vera, Jean-Charles Dupont, and Hugo De Backer
Atmos. Meas. Tech., 9, 5347–5365,Short summary
Air traffic at busy airports can be significantly disrupted because low visibility due to fog makes it unsafe to take off, land and taxi on the ground. In this paper we show how automatic profiling lidar ceilometer measurements, available at most airports, can be used to provide pre-fog alert information, and hence help airport weather forecasters to better predict these low visibility conditions. This research was carried out in the context of a field campaign at Paris CDG airport (France).
Agnieszka E. Czerwińska, Janusz W. Krzyścin, Janusz Jarosławski, and Michał Posyniak
Atmos. Chem. Phys., 16, 13641–13651,Short summary
This article presents a comparison between the two surface-UV dose series, measured with Brewer spectrophotometers working simultaneously at two different sites in Poland: in a large city agglomeration and in the suburbs. We consider whether the city of Warsaw acts as a shield from ultraviolet overexposure. Our study proves that the UV level in Warsaw is slightly lower than that found in cleaner suburbs of the city.
Dimitra Founda, Stelios Kazadzis, Nikolaos Mihalopoulos, Evangelos Gerasopoulos, Maria Lianou, and Panagiotis I. Raptis
Atmos. Chem. Phys., 16, 11219–11236,Short summary
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.
Claudia Di Biagio, Paola Formenti, Lionel Doppler, Cécile Gaimoz, Noel Grand, Gerard Ancellet, Jean-Luc Attié, Silvia Bucci, Philippe Dubuisson, Federico Fierli, Marc Mallet, and François Ravetta
Atmos. Chem. Phys., 16, 10591–10607,Short summary
Pollution aerosols strongly influence the composition of the Western Mediterranean, but at present little is known on their optical properties. Here, we report observations of pollution aerosols measured during the TRAQA airborne campaign in summer 2012. Data from this study indicate a large variability of the absorption for pollution particles. This variability strongly influences their direct radiative effect, with possible consequences on the hydrological cycle in this part of the basin.
Roeland Van Malderen, Marc A. F. Allaart, Hugo De Backer, Herman G. J. Smit, and Dirk De Muer
Atmos. Meas. Tech., 9, 3793–3816,Short summary
Thanks to the Montreal Protocol regulations for ozone-depleting substances, the decline of ozone concentrations has been stopped. A remaining major issue today is if the onset of ozone recovery can be detected. Ozonesondes have provided vertical distribution of ozone with high vertical resolution for several decades. In this study, we investigate how different operating procedures at ozonesonde stations and different ozonesonde data correction strategies affect trends in ozone concentrations.
Stelios M. Potirakis, Yiannis Contoyiannis, Nikolaos S. Melis, John Kopanas, George Antonopoulos, Georgios Balasis, Charalampos Kontoes, Constantinos Nomicos, and Konstantinos Eftaxias
Nonlin. Processes Geophys., 23, 223–240,Short summary
Based on the methods of critical fluctuations and natural time, we have shown that the fracture-induced MHz electromagnetic emissions recorded by two stations in our network prior to two recent significant earthquakes that occurred in Cephalonia present criticality characteristics, implying that they emerge from a system in critical state.
Anu Heikkilä, Jussi Kaurola, Kaisa Lakkala, Juha Matti Karhu, Esko Kyrö, Tapani Koskela, Ola Engelsen, Harry Slaper, and Gunther Seckmeyer
Geosci. Instrum. Method. Data Syst., 5, 333–345,Short summary
Solar spectral UV irradiance data measured by the Brewer #037 spectroradiometer in Sodankylä, Finland, in 1990–2014 were examined for their quality flags given by the quality assurance (QA) tools of the European UV DataBase (EUVDB). Statistical analysis on the flags was performed, and five cases were investigated in detail. The results can be used in further development of the quality control/QA tools and selection of cases of exceptional atmospheric conditions for process studies.
Kaisa Lakkala, Hanne Suokanerva, Juha Matti Karhu, Antti Aarva, Antti Poikonen, Tomi Karppinen, Markku Ahponen, Henna-Reetta Hannula, Anna Kontu, and Esko Kyrö
Geosci. Instrum. Method. Data Syst., 5, 315–320,Short summary
This paper describes the laboratory facilities at the Finnish Meteorological Institute – Arctic Research Centre (FMI-ARC). They comprise an optical laboratory, a facility for biological studies, and an office. The facilities are ideal for responding to the needs of international multidisciplinary research, giving the possibility to calibrate and characterize the research instruments as well as handle and store samples.
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,Short summary
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,Short summary
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.
Tomi Karppinen, Kaisa Lakkala, Juha M. Karhu, Pauli Heikkinen, Rigel Kivi, and Esko Kyrö
Geosci. Instrum. Method. Data Syst., 5, 229–239,Short summary
In this paper, a 26-year-long time series of total ozone column above Arctic Research Center in Sodankylä is presented. The time series is produced using a uniform method, presented in the paper, for retrieving the ozone column from the measurements. The data are checked for obvious errors and filtered automatically and manually to ensure that only good-quality data are delivered to public databases. Some features of the time series are highlighted and availability of the measurements is presented.
Jakke Sakari Mäkelä, Kaisa Lakkala, Tapani Koskela, Tomi Karppinen, Juha Matti Karhu, Vladimir Savastiouk, Hanne Suokanerva, Jussi Kaurola, Antti Arola, Anders Vilhelm Lindfors, Outi Meinander, Gerrit de Leeuw, and Anu Heikkilä
Geosci. Instrum. Method. Data Syst., 5, 193–203,Short summary
We describe the steps that are used at the Finnish Meteorological Institute (FMI) to process spectral ultraviolet (UV) radiation measurements made with its three Brewer spectrophotometers, located in Sodankylä (67° N) and Jokioinen (61° N). Multiple corrections are made to the data in near-real time and quality control is also performed automatically. Several data products are produced, including the near-real-time UV index and various daily dosages, and submitted to databases.
Henri Diémoz, Kostas Eleftheratos, Stelios Kazadzis, Vassilis Amiridis, and Christos S. Zerefos
Atmos. Meas. Tech., 9, 1871–1888,Short summary
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.
Ilias Fountoulakis, Alberto Redondas, Alkiviadis F. Bais, Juan José Rodriguez-Franco, Konstantinos Fragkos, and Alexander Cede
Atmos. Meas. Tech., 9, 1799–1816,Short summary
The dead time (DT) is characteristic for each Brewer spectrophotometer and non-proper correction of the raw data for its effect may lead to important errors in UV, AOD and TOC measurements. Quantitative estimation of the DT-related uncertainties shown that a 2 ns error in the DT may lead to errors greater than 1 % in TOC. The operational algorithm for the DT calculation and correction is validated and the development of new methods for the estimation of DT is described.
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,Short summary
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.
Klaus Gierens and Kostas Eleftheratos
Atmos. Chem. Phys., 16, 4159–4169,Short summary
Upper tropospheric humidity (UTH) is a weighted mean of the relative humidity (RH) in the upper troposphere. It can change due to climate change even when the relative humidity would stay unchanged because the weighting functions will alter. We show that changes of UTH expected during 30 years of tropospheric warming are typically less than 1 % in magnitude and mostly negative. Larger positive changes of UTH (as found in an analysis of 30 years of satellite data) point thus to an increase of RH.
Ilias Fountoulakis, Alkiviadis F. Bais, Konstantinos Fragkos, Charickleia Meleti, Kleareti Tourpali, and Melina Maria Zempila
Atmos. Chem. Phys., 16, 2493–2505,Short summary
Short- and long-term variability of spectral UV irradiance at Thessaloniki, Greece, is discussed in association with changes in total ozone column, aerosols and cloudiness. The UV data set from two Brewer spectrophotometers is used for the analysis. For the entire period 1994–2014, positive, statistically significant increases of UV irradiance were found, mainly attributable to changes in aerosols. UV irradiance is mainly increased from 1994 to 2006 and remains relatively stable thereafter.
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,Short summary
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.
G. Alexandri, A. K. Georgoulias, P. Zanis, E. Katragkou, A. Tsikerdekis, K. Kourtidis, and C. Meleti
Atmos. Chem. Phys., 15, 13195–13216,Short summary
It is shown here that RegCM4 regional climate model adequately simulates surface solar radiation (SSR) over Europe but significantly over/underestimates several parameters that determine the transmission of solar radiation in the atmosphere. The agreement between RegCM4 and satellite-based SSR observations is actually a result of the conflicting effect of these parameters. We suggest that there should be a reassessment of the way these parameters are represented within this and other models.
C. Di Biagio, L. Doppler, C. Gaimoz, N. Grand, G. Ancellet, J.-C. Raut, M. Beekmann, A. Borbon, K. Sartelet, J.-L. Attié, F. Ravetta, and P. Formenti
Atmos. Chem. Phys., 15, 9611–9630,Short summary
Observations from this study indicate that continental pollution largely affects the atmospheric composition and structure of the western Mediterranean basin. Pollution plumes reach 3000-4000 m in altitude and present a very complex and highly stratified structure, characterized by fresh and aged layers both in the boundary layer and in the free troposphere. Also we report the observations of high levels of ultrafine particles over the basin, possibly linked to new particle formation events.
C. K. Carbajal Henken, L. Doppler, R. Lindstrot, R. Preusker, and J. Fischer
Atmos. Meas. Tech., 8, 3419–3431,Short summary
This work presents a study on the sensitivity of two independent satellite cloud height retrievals to cloud vertical distribution. The difference in sensitivity of an oxygen-A absorption band and a thermal infrared based cloud height retrieval, the former being more sensitive to cloud vertical distribution, is exploited by relating the cloud height differences to cloud vertical extent. This could potentially provide additional information on cloud vertical distribution on a global scale.
G. Bernhard, A. Arola, A. Dahlback, V. Fioletov, A. Heikkilä, B. Johnsen, T. Koskela, K. Lakkala, T. Svendby, and J. Tamminen
Atmos. Chem. Phys., 15, 7391–7412,Short summary
Surface erythemal UV data from the Ozone Monitoring Instrument (OMI) are validated for high northern latitudes (Arctic and Scandinavia) using ground-based measurements. The bias in OMI data caused by incorrect assumptions of the surface albedo are quantified and the mechanism that causes this bias is discussed. Methods to improve the accuracy of OMI data products are presented.
J. Bilbao, R. Román, C. Yousif, D. Mateos, and A. de Miguel
Adv. Sci. Res., 12, 147–155,Short summary
A solar radiation measurement campaign was performed in the south-eastern village of Marsaxlokk (35º 50' N; 14º 33' E; 10 m a.s.l.), Malta, between 15 May and 15 October 2012. Erythemal solar radiation (UVER), horizontal global and diffuse components were recorded. Aerosols effects on solar irradiances are evaluated using the Aerosol Modification factor (AMF). Results indicate a greater aerosol effect on UVER than on global solar irradiance. Several dust event trajectories are identified.
V. Amiridis, E. Marinou, A. Tsekeri, U. Wandinger, A. Schwarz, E. Giannakaki, R. Mamouri, P. Kokkalis, I. Binietoglou, S. Solomos, T. Herekakis, S. Kazadzis, E. Gerasopoulos, E. Proestakis, M. Kottas, D. Balis, A. Papayannis, C. Kontoes, K. Kourtidis, N. Papagiannopoulos, L. Mona, G. Pappalardo, O. Le Rille, and A. Ansmann
Atmos. Chem. Phys., 15, 7127–7153,Short summary
LIVAS is a 3-D multi-wavelength global aerosol and cloud optical database optimized for future space-based lidar end-to-end simulations of realistic atmospheric scenarios as well as retrieval algorithm testing activities. The global database is based on CALIPSO observations at 532nm, while for the conversion at 355nm EARLINET data are utilized.
J. Svensson, A. Virkkula, O. Meinander, N. Kivekäs, H.-R. Hannula, O. Järvinen, J. I. Peltoniemi, M. Gritsevich, A. Heikkilä, A. Kontu, A.-P. Hyvärinen, K. Neitola, D. Brus, P. Dagsson-Waldhauserova, K. Anttila, T. Hakala, H. Kaartinen, M. Vehkamäki, G. de Leeuw, and H. Lihavainen
The Cryosphere Discuss.,
Revised manuscript not acceptedShort summary
Soot's (including black carbon and organics) negative effect on a natural snow pack is experimentally addressed in this paper through a series of experiments. Soot concentrations in the snow in the range of 200-200 000 ppb verify the negative effects on the albedo, the physical snow characteristics, as well as increasing the melt rate of the snow pack. Our experimental data generally agrees when compared with the Snow, Ice and Aerosol Radiation model.
M. R. A. Pitkänen, A. Arola, K. Lakkala, T. Koskela, and A. V. Lindfors
Atmos. Meas. Tech. Discuss.,
Revised manuscript not accepted
R. Román, J. Bilbao, and A. de Miguel
Atmos. Chem. Phys., 15, 375–391,Short summary
This paper develops two models for the reconstruction of ultraviolet erythemal radiation (UVER). The models are based on shortwave radiation (SW) and sunshine duration measurements. Both models are used to reconstruct UVER irradiation at nine Spanish places from 1950 to 2011. The trends of UVER are calculated at different periods. UVER presented a brightening phenomenon, but not dimming, due to the ozone depletion until the mid-1990s.
H. Diémoz, A. M. Siani, A. Redondas, V. Savastiouk, C. T. McElroy, M. Navarro-Comas, and F. Hase
Atmos. Meas. Tech., 7, 4009–4022,Short summary
- A new algorithm to retrieve nitrogen dioxide by Brewer spectrophotometers was developed. - Direct sun and zenith sky data recorded at the Izaña observatory were processed with the new algorithm and compared to co-located reference instruments. - The measurement uncertainty was thoroughly determined by using a Monte Carlo technique. - The new algorithm can be applied to more than 60 Brewers around the world.
V. De Bock, H. De Backer, R. Van Malderen, A. Mangold, and A. Delcloo
Atmos. Chem. Phys., 14, 12251–12270,
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,
C. Gielen, M. Van Roozendael, F. Hendrick, G. Pinardi, T. Vlemmix, V. De Bock, H. De Backer, C. Fayt, C. Hermans, D. Gillotay, and P. Wang
Atmos. Meas. Tech., 7, 3509–3527,
M. Karl, N. Castell, D. Simpson, S. Solberg, J. Starrfelt, T. Svendby, S.-E. Walker, and R. F. Wright
Atmos. Chem. Phys., 14, 8533–8557,
R. Van Malderen, H. Brenot, E. Pottiaux, S. Beirle, C. Hermans, M. De Mazière, T. Wagner, H. De Backer, and C. Bruyninx
Atmos. Meas. Tech., 7, 2487–2512,
C. S. Zerefos, K. Tourpali, P. Zanis, K. Eleftheratos, C. Repapis, A. Goodman, D. Wuebbles, I. S. A. Isaksen, and J. Luterbacher
Atmos. Chem. Phys., 14, 7705–7720,
K. Gierens, K. Eleftheratos, and L. Shi
Atmos. Chem. Phys., 14, 7533–7541,
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,
A. Kreuter, R. Buras, B. Mayer, A. Webb, R. Kift, A. Bais, N. Kouremeti, and M. Blumthaler
Atmos. Chem. Phys., 14, 5989–6002,
M. Taylor, S. Kazadzis, and E. Gerasopoulos
Atmos. Meas. Tech., 7, 839–858,
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,
E. Pichelli, R. Ferretti, M. Cacciani, A. M. Siani, V. Ciardini, and T. Di Iorio
Atmos. Meas. Tech., 7, 315–332,
A. Gkikas, N. Hatzianastassiou, N. Mihalopoulos, V. Katsoulis, S. Kazadzis, J. Pey, X. Querol, and O. Torres
Atmos. Chem. Phys., 13, 12135–12154,
G. Bernhard, A. Dahlback, V. Fioletov, A. Heikkilä, B. Johnsen, T. Koskela, K. Lakkala, and T. Svendby
Atmos. Chem. Phys., 13, 10573–10590,
A. Stenke, C. R. Hoyle, B. Luo, E. Rozanov, J. Gröbner, L. Maag, S. Brönnimann, and T. Peter
Atmos. Chem. Phys., 13, 9713–9729,
A. Kreuter and M. Blumthaler
Atmos. Meas. Tech., 6, 1845–1854,
T. Egorova, E. Rozanov, J. Gröbner, M. Hauser, and W. Schmutz
Atmos. Chem. Phys., 13, 3811–3823,
A. V. Lindfors, N. Kouremeti, A. Arola, S. Kazadzis, A. F. Bais, and A. Laaksonen
Atmos. Chem. Phys., 13, 3733–3741,
A. Kreuter, S. Wuttke, and M. Blumthaler
Atmos. Meas. Tech., 6, 99–103,
Related subject area
Subject: Aerosols | Technique: Remote Sensing | Topic: Validation and IntercomparisonsPerformance evaluation for retrieving aerosol optical depth from the Directional Polarimetric Camera (DPC) based on the GRASP algorithmExtended validation and evaluation of the OLCI-SLSTR Synergy aerosol product (SY_2_AOD) on Sentinel-3Assessment of tropospheric CALIPSO Version 4.2 aerosol types over the ocean using independent CALIPSO–SODA lidar ratiosEvaluation of UV–visible MAX-DOAS aerosol profiling products by comparison with ceilometer, sun photometer, and in situ observations in Vienna, AustriaExperimental assessment of a micro-pulse lidar system in comparison with reference lidar measurements for aerosol optical properties retrievalCharacterization of aerosol size properties from measurements of spectral optical depth: a global validation of the GRASP-AOD code using long-term AERONET dataRetrieval of aerosol fine-mode fraction over China from satellite multiangle polarized observations: validation and comparisonRetrieval and evaluation of tropospheric-aerosol extinction profiles using multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements over Athens, GreeceEmpirically derived parameterizations of the direct aerosol radiative effect based on ORACLES aircraft observationsTROPOMI aerosol products: evaluation and observations of synoptic-scale carbonaceous aerosol plumes during 2018–2020Combining low-cost, surface-based aerosol monitors with size-resolved satellite data for air quality applicationsInterannual 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 lidarAerosol data assimilation in the MOCAGE chemical transport model during the TRAQA/ChArMEx campaign: lidar observationsApplication of low-cost fine particulate mass monitors to convert satellite aerosol optical depth to surface concentrations in North America and AfricaEvaluation of the OMPS/LP stratospheric aerosol extinction product using SAGE III/ISS observationsA fast visible-wavelength 3D radiative transfer model for numerical weather prediction visualization and forward modelingA first comparison of TROPOMI aerosol layer height (ALH) to CALIOP dataThe 2018 fire season in North America as seen by TROPOMI: aerosol layer height intercomparisons and evaluation of model-derived plume heightsEvaluation of satellite-based aerosol datasets and the CAMS reanalysis over the ocean utilizing shipborne reference observationsAerosol and cloud top height information of Envisat MIPAS measurementsAssessment of urban aerosol pollution over the Moscow megacity by the MAIAC aerosol productAerosol retrievals from different polarimeters during the ACEPOL campaign using a common retrieval algorithmA review and framework for the evaluation of pixel-level uncertainty estimates in satellite aerosol remote sensingAnalysis of global three-dimensional aerosol structure with spectral radiance matchingA comparative evaluation of Aura-OMI and SKYNET near-UV single-scattering albedo productsAerosol measurements with a shipborne Sun–sky–lunar photometer and collocated multiwavelength Raman polarization lidar over the Atlantic OceanIntercomparison of aerosol volume size distributions derived from AERONET ground-based remote sensing and LARGE in situ aircraft profiles during the 2011–2014 DRAGON and DISCOVER-AQ experimentsValidation, comparison, and integration of GOCI, AHI, MODIS, MISR, and VIIRS aerosol optical depth over East Asia during the 2016 KORUS-AQ campaignAerosol optical depth comparison between GAW-PFR and AERONET-Cimel radiometers from long-term (2005–2015) 1 min synchronous measurementsAccuracy assessment of MODIS land aerosol optical thickness algorithms using AERONET measurements over North AmericaInvestigations into the development of a satellite-based aerosol climate data record using ATSR-2, AATSR and AVHRR data over north-eastern China from 1987 to 2012Stratospheric aerosol characteristics from space-borne observations: extinction coefficient and Ångström exponentRetrieval of aerosol properties from ceilometer and photometer measurements: long-term evaluation with in situ data and statistical analysis at Montsec (southern Pyrenees)Novel aerosol extinction coefficients and lidar ratios over the ocean from CALIPSO–CloudSat: evaluation and global statisticsRadiometric calibration of a non-imaging airborne spectrometer to measure the Greenland ice sheet surfaceAerosol optical depth retrievals in central Amazonia from a multi-filter rotating shadow-band radiometer calibrated on-siteAerosol backscatter profiles from ceilometers: validation of water vapor correction in the framework of CeiLinEx2015Aerosol optical properties derived from POLDER-3/PARASOL (2005–2013) over the western Mediterranean Sea – Part 1: Quality assessment with AERONET and in situ airborne observationsExploring systematic offsets between aerosol products from the two MODIS sensorsValidation of MODIS 3 km land aerosol optical depth from NASA's EOS Terra and Aqua missionsComparison of dust-layer heights from active and passive satellite sensorsVertical profiles of aerosol mass concentration derived by unmanned airborne in situ and remote sensing instruments during dust eventsIntercomparison of aerosol measurements performed with multi-wavelength Raman lidars, automatic lidars and ceilometers in the framework of INTERACT-II campaignComparison of aerosol optical depth from satellite (MODIS), sun photometer and broadband pyrheliometer ground-based observations in CubaSpatial distribution analysis of the OMI aerosol layer height: a pixel-by-pixel comparison to CALIOP observationsCharacterization of smoke and dust episode over West Africa: comparison of MERRA-2 modeling with multiwavelength Mie–Raman lidar observationsCollocation mismatch uncertainties in satellite aerosol retrieval validationConsistency of aerosols above clouds characterization from A-Train active and passive measurementsMixing layer height as an indicator for urban air quality?
Shikuan Jin, Yingying Ma, Cheng Chen, Oleg Dubovik, Jin Hong, Boming Liu, and Wei Gong
Atmos. Meas. Tech., 15, 4323–4337,Short summary
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
Larisa Sogacheva, Matthieu Denisselle, Pekka Kolmonen, Timo H. Virtanen, Peter R. J. North, Claire Henocq, Silvia Scifoni, and Steffen Dransfeld
Atmos. Meas. Tech. Discuss.,
Revised manuscript accepted for AMTShort summary
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 onboard the Sentinel-3A and -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 over land. Validation statistics are often slightly better for S3B and in the Southern Hemisphere.
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,Short summary
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.
Stefan F. Schreier, Tim Bösch, Andreas Richter, Kezia Lange, Michael Revesz, Philipp Weihs, Mihalis Vrekoussis, and Christoph Lotteraner
Atmos. Meas. Tech., 14, 5299–5318,Short summary
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,Short summary
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,Short summary
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,Short summary
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,
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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,Short summary
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.
Debora Griffin, Christopher Sioris, Jack Chen, Nolan Dickson, Andrew Kovachik, Martin de Graaf, Swadhin Nanda, Pepijn Veefkind, Enrico Dammers, Chris A. McLinden, Paul Makar, and Ayodeji Akingunola
Atmos. Meas. Tech., 13, 1427–1445,Short summary
This study looks into validating the aerosol layer height product from the recently launched TROPOspheric Monitoring Instrument (TROPOMI) for forest fire plume through comparisons with two other satellite products, and interpreting differences due to the individual measurement techniques. These satellite observations are compared to predicted plume heights from Environment and Climate Change's air quality forecast model.
Jonas Witthuhn, Anja Hünerbein, and Hartwig Deneke
Atmos. Meas. Tech., 13, 1387–1412,Short summary
Reliable reference measurements over ocean are essential for the evaluation and improvement of satellite- and model-based aerosol datasets. Here, a uniqe set of shipborne reference aerosol products obtained from Microtops sunphotometer and GUVis-3511 shadowband radiometer observations are compared to aerosol products from the MODIS and SEVIRI satellite sensors, and the CAMS reanalysis over the Atlantic Ocean. The present evaluation highlights the importance of an aerosol-type based analysis.
Sabine Griessbach, Lars Hoffmann, Reinhold Spang, Peggy Achtert, Marc von Hobe, Nina Mateshvili, Rolf Müller, Martin Riese, Christian Rolf, Patric Seifert, and Jean-Paul Vernier
Atmos. Meas. Tech., 13, 1243–1271,Short summary
In this paper we study the cloud top height derived from MIPAS measurements. Previous studies showed contradictory results with respect to MIPAS, both underestimating and overestimating cloud top height. We used simulations and found that overestimation and/or underestimation depend on cloud extinction. To support our findings we compared MIPAS cloud top heights of volcanic sulfate aerosol with measurements from CALIOP, ground-based lidar, and ground-based twilight measurements.
Ekaterina Y. Zhdanova, Natalia Y. Chubarova, and Alexei I. Lyapustin
Atmos. Meas. Tech., 13, 877–891,Short summary
We estimated the distribution of aerosol optical thickness (AOT) with a spatial resolution of 1 km over the Moscow megacity using the MAIAC satellite aerosol product from May to September over the years 2000–2017. We revealed that the MAIAC product is a reliable instrument for assessing the spatial features of urban aerosol pollution and its temporal dynamics. The local aerosol effect is about 0.02–0.04 in AOT in the visible spectral range over the Moscow megacity.
Guangliang Fu, Otto Hasekamp, Jeroen Rietjens, Martijn Smit, Antonio Di Noia, Brian Cairns, Andrzej Wasilewski, David Diner, Felix Seidel, Feng Xu, Kirk Knobelspiesse, Meng Gao, Arlindo da Silva, Sharon Burton, Chris Hostetler, John Hair, and Richard Ferrare
Atmos. Meas. Tech., 13, 553–573,Short summary
In this paper, we present aerosol retrieval results from the ACEPOL (Aerosol Characterization from Polarimeter and Lidar) campaign, which was a joint initiative between NASA and SRON (the Netherlands Institute for Space Research). We perform aerosol retrievals from different multi-angle polarimeters employed during the ACEPOL campaign and evaluate them against ground-based AERONET measurements and High Spectral Resolution Lidar-2 (HSRL-2) measurements.
Andrew M. Sayer, Yves Govaerts, Pekka Kolmonen, Antti Lipponen, Marta Luffarelli, Tero Mielonen, Falguni Patadia, Thomas Popp, Adam C. Povey, Kerstin Stebel, and Marcin L. Witek
Atmos. Meas. Tech., 13, 373–404,Short summary
Satellite measurements of the Earth are routinely processed to estimate useful quantities; one example is the amount of atmospheric aerosols (which are particles such as mineral dust, smoke, volcanic ash, or sea spray). As with all measurements and inferred quantities, there is some degree of uncertainty in this process. There are various methods to estimate these uncertainties. A related question is the following: how reliable are these estimates? This paper presents a method to assess them.
Dong Liu, Sijie Chen, Chonghui Cheng, Howard W. Barker, Changzhe Dong, Ju Ke, Shuaibo Wang, and Zhuofan Zheng
Atmos. Meas. Tech., 12, 6541–6556,Short summary
Aerosols are one of the drivers of climate change, and more information about aerosol vertical distribution is needed to analyze the role of aerosols in the atmosphere. In this work, we match and substitute a pixel along the lidar ground track for every pixel that is not on the track based on the radiance measured by a passive imager, therefore expanding the atmosphere profiles to a nearby region. The accuracy of the construction is confirmed through a procedure mimicking the construction.
Hiren Jethva and Omar Torres
Atmos. Meas. Tech., 12, 6489–6503,Short summary
The intercomparison of satellite- and ground-measured aerosol absorption properties, such as presented here using Aura-OMI and SKYNET sensors, constitutes an important exercise to evaluate relative performance, track algorithm changes, and to diagnose retrieval accuracy and issues. The two datasets are found to agree reasonably well under moderate to higher aerosol loading but show disagreement under lower aerosol amounts due to retrieval issues in both techniques.
Zhenping Yin, Albert Ansmann, Holger Baars, Patric Seifert, Ronny Engelmann, Martin Radenz, Cristofer Jimenez, Alina Herzog, Kevin Ohneiser, Karsten Hanbuch, Luc Blarel, Philippe Goloub, Gaël Dubois, Stephane Victori, and Fabrice Maupin
Atmos. Meas. Tech., 12, 5685–5698,Short summary
A new shipborne Sun–sky–lunar photometer was validated through comparisons with collocated MICROTOPS II and multiwavelength Raman polarization lidar measurements during two trans-Atlantic cruises. A full diurnal cycle of mixed dust–smoke episode was captured by both the shipborne photometer and lidar. The coefficient of determination for the linear regression between MICROTOPS II and the shipborne photometer was 0.993 for AOD at 500 nm based on the entire dataset.
Joel S. Schafer, Tom F. Eck, Brent N. Holben, Kenneth L. Thornhill, Luke D. Ziemba, Patricia Sawamura, Richard H. Moore, Ilya Slutsker, Bruce E. Anderson, Alexander Sinyuk, David M. Giles, Alexander Smirnov, Andreas J. Beyersdorf, and Edward L. Winstead
Atmos. Meas. Tech., 12, 5289–5301,Short summary
Two independent datasets of column-integrated size distributions of atmospheric aerosols were compared during four 1-month regional campaigns from 2011 to 2014 in four US states. One set of measurements was from observations at multiple locations at the surface using retrievals from sun photometers, while the other relied on in situ aircraft sampling. These campaigns represent the most extensive comparison of AERONET size distributions with aircraft sampling of particle size on record.
Myungje Choi, Hyunkwang Lim, Jhoon Kim, Seoyoung Lee, Thomas F. Eck, Brent N. Holben, Michael J. Garay, Edward J. Hyer, Pablo E. Saide, and Hongqing Liu
Atmos. Meas. Tech., 12, 4619–4641,Short summary
Satellite-based aerosol optical depth (AOD) products have been improved continuously and available from multiple low Earth orbit sensors, such as MODIS, MISR, and VIIRS, and geostationary sensors, such as GOCI and AHI, over East Asia. These multi-satellite AOD products are validated, intercompared, analyzed, and integrated to understand different characteristics, such as quality and spatio-temporal coverage, focused on several aerosol transportation cases during the 2016 KORUS-AQ campaign.
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,Short summary
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.
Hiren Jethva, Omar Torres, and Yasuko Yoshida
Atmos. Meas. Tech., 12, 4291–4307,Short summary
Accuracy assessment of the satellite-retrieved aerosol properties is an important exercise to validate and track the changes in the retrieval algorithm. Here, for the first time, three standard aerosol products derived from MODIS Aqua are compared against the ground-based AERONET dataset over the North American region. The present validation analysis provides guidance in the development of inversion schemes to derive aerosol properties from existing and future MODIS-like sensors.
Yahui Che, Jie Guang, Gerrit de Leeuw, Yong Xue, Ling Sun, and Huizheng Che
Atmos. Meas. Tech., 12, 4091–4112,Short summary
The use of AOD data retrieved from ATSR-2, AATSR and AVHRR to produce a very long time series is investigated. The study is made over a small area in northern China with a large variation of AOD values. Sun photometer data from AERONET and CARSNET and radiance-derived AOD are used as reference. The results show that all data sets compare well. However, AVHRR underestimates high AOD (mainly occurring in summer) but performs better than (A)ATSR in winter.
Elizaveta Malinina, Alexei Rozanov, Landon Rieger, Adam Bourassa, Heinrich Bovensmann, John P. Burrows, and Doug Degenstein
Atmos. Meas. Tech., 12, 3485–3502,Short summary
This paper covers the problems related to the derivation of aerosol extinction coefficients and Ångström exponents from space-borne instruments working in limb and occultation viewing geometries. Aerosol extinction coefficients and Ångström exponents were calculated from the SCIAMACHY aerosol particle size data set. The results were compared with the data from SAGE II and OSIRIS. The Ångström exponent in the tropical regions and its dependency on particle size parameters are discussed.
Gloria Titos, Marina Ealo, Roberto Román, Alberto Cazorla, Yolanda Sola, Oleg Dubovik, Andrés Alastuey, and Marco Pandolfi
Atmos. Meas. Tech., 12, 3255–3267,Short summary
We present new results of vertically resolved extensive aerosol optical properties (backscattering, scattering and extinction) and volume concentrations retrieved with the GRASP algorithm from ceilometer and photometer measurements. Long-term evaluation with in situ data gathered at the Montsec mountaintop observatory (northeastern Spain) shows good agreement, being a step forward towards a better representation of aerosol vertical distribution with wide spatial coverage.
David Painemal, Marian Clayton, Richard Ferrare, Sharon Burton, Damien Josset, and Mark Vaughan
Atmos. Meas. Tech., 12, 2201–2217,Short summary
We present 1 year of a new CALIOP-based aerosol extinction coefficient and lidar ratio over the ocean, with the goal of providing a flexible dataset for climate research as well as independent retrievals that can be helpful for refining CALIPSO Science Team algorithms. The retrievals are derived by constraining the lidar equation with an aerosol optical depth estimated from cross-calibrated CALIOP and CloudSat surface echos.
Christopher J. Crawford, Jeannette van den Bosch, Kelly M. Brunt, Milton G. Hom, John W. Cooper, David J. Harding, James J. Butler, Philip W. Dabney, Thomas A. Neumann, Craig S. Cleckner, and Thorsten Markus
Atmos. Meas. Tech., 12, 1913–1933,Short summary
This paper presents laboratory and in-flight radiometric methods to calibrate and deploy a full-spectrum non-imaging airborne visible-to-shortwave infrared (VSWIR) spectrometer to measure polar ice sheet surface optical properties. Using an atmospheric radiative transfer model and coincident Landsat 8 multispectral image, this study concluded that it is possible to measure bright Greenland ice and dark bare rock/soil targets at an airborne remote sensing uncertainty of between 0.6 and 4.7.
Nilton E. Rosário, Thamara Sauini, Theotonio Pauliquevis, Henrique M. J. Barbosa, Marcia A. Yamasoe, and Boris Barja
Atmos. Meas. Tech., 12, 921–934,Short summary
Does pristine Amazonian forest atmosphere provide successful calibration of a Sun photometer based on the Langley plot method? This question emerged from the challenge of maintaining regular calibration of a Sun photometer dedicated to long-term monitoring of aerosol optical properties in Amazonia, far from clean mountaintops. Our results show that on-site calibrated Sun photometers, under pristine Amazonian conditions, are able to provide consistent retrieval of aerosol optical depth.
Matthias Wiegner, Ina Mattis, Margit Pattantyús-Ábrahám, Juan Antonio Bravo-Aranda, Yann Poltera, Alexander Haefele, Maxime Hervo, Ulrich Görsdorf, Ronny Leinweber, Josef Gasteiger, Martial Haeffelin, Frank Wagner, Jan Cermak, Katerina Komínková, Mike Brettle, Christoph Münkel, and Kornelia Pönitz
Atmos. Meas. Tech., 12, 471–490,Short summary
Many ceilometers are influenced by water vapor absorption in the spectral range around 910 nm. Thus, a correction is required to retrieve aerosol optical properties. Validation of this correction scheme was performed in the framework of CeiLinEx2015 for several ceilometers with good agreement for Vaisala's CL51 ceilometer. For future applications we recommend monitoring the emitted wavelength and providing
darkmeasurements on a regular basis to be able to correct for signal artifacts.
Paola Formenti, Lydie Mbemba Kabuiku, Isabelle Chiapello, Fabrice Ducos, François Dulac, and Didier Tanré
Atmos. Meas. Tech., 11, 6761–6784,Short summary
Aerosol particles from natural and anthropogenic sources are climate regulators as they can counteract or amplify the warming effect of greenhouse gases, but are difficult to observe due to their temporal and spatial variability. Satellite sensors can provide the needed global coverage but need validation. In this paper we explore the capability of the POLDER-3 advanced space-borne sensor to observe aerosols over the western Mediterranean region.
Robert C. Levy, Shana Mattoo, Virginia Sawyer, Yingxi Shi, Peter R. Colarco, Alexei I. Lyapustin, Yujie Wang, and Lorraine A. Remer
Atmos. Meas. Tech., 11, 4073–4092,Short summary
Global aerosol data sets are essential for assessing climate-related questions. When comparing data sets derived from twin satellite sensors, we find consistent global offsets between morning and afternoon observations. Applying satellite-like sampling to a global model derives much weaker morning/afternoon offsets, suggesting that the observational differences are due to calibration. However, applying additional calibration corrections appears to reduce (but not remove) the global offsets.
Pawan Gupta, Lorraine A. Remer, Robert C. Levy, and Shana Mattoo
Atmos. Meas. Tech., 11, 3145–3159,Short summary
In this study, we perform global validation of MODIS high-resolution (3 km) AOD over global land by comparing against AERONET measurements. The MODIS–AERONET collocated data sets consist of 161 410 high-confidence AOD pairs from 2000 to 2015 for Terra MODIS and 2003 to 2015 for Aqua MODIS. We find that 62.5 and 68.4 % of AODs retrieved from Terra MODIS and Aqua MODIS, respectively, fall within previously published expected error.
Arve Kylling, Sophie Vandenbussche, Virginie Capelle, Juan Cuesta, Lars Klüser, Luca Lelli, Thomas Popp, Kerstin Stebel, and Pepijn Veefkind
Atmos. Meas. Tech., 11, 2911–2936,Short summary
The aerosol layer height is one of four aerosol parameters which is needed to enhance our understanding of aerosols' role in the climate system. Both active and passive measurement methods may be used to estimate the aerosol layer height. Aerosol height estimates made from passive infrared and solar satellite sensors measurements are compared with satellite-borne lidar estimates. There is considerable variation between the retrieved dust heights and how they compare with the lidar.
Dimitra Mamali, Eleni Marinou, Jean Sciare, Michael Pikridas, Panagiotis Kokkalis, Michael Kottas, Ioannis Binietoglou, Alexandra Tsekeri, Christos Keleshis, Ronny Engelmann, Holger Baars, Albert Ansmann, Vassilis Amiridis, Herman Russchenberg, and George Biskos
Atmos. Meas. Tech., 11, 2897–2910,Short summary
The paper's scope is to evaluate the performance of in situ atmospheric aerosol instrumentation on board unmanned aerial vehicles (UAVs) and the performance of algorithms used to calculate the aerosol mass from remote sensing instruments by comparing the two independent techniques to each other. Our results indicate that UAV-based aerosol measurements (using specific in situ and remote sensing instrumentation) can provide reliable ways to determine the aerosol mass throughout the atmosphere.
Fabio Madonna, Marco Rosoldi, Simone Lolli, Francesco Amato, Joshua Vande Hey, Ranvir Dhillon, Yunhui Zheng, Mike Brettle, and Gelsomina Pappalardo
Atmos. Meas. Tech., 11, 2459–2475,Short summary
The accurate monitoring of climate based on the use of low-cost and low-maintenance automatic system represents one of the challenges for the scientific community and instrument manufacturers for the next decade. In the frame of two experiments, INTERACT and INTERACT-II, taking place at CIAO (CNR-IMAA Atmospheric Observatory) in Tito Scalo, Potenza, Italy, commercial low-cost lidars have been compared with advanced lidar systems to assess their performances.
Juan Carlos Antuña-Marrero, Victoria Cachorro Revilla, Frank García Parrado, Ángel de Frutos Baraja, Albeth Rodríguez Vega, David Mateos, René Estevan Arredondo, and Carlos Toledano
Atmos. Meas. Tech., 11, 2279–2293,Short summary
Comparing AOD measurements from MODIS (Terra and Aqua), sun photometer and pyrheliometers broadband instruments in Cuba.
Julien Chimot, J. Pepijn Veefkind, Tim Vlemmix, and Pieternel F. Levelt
Atmos. Meas. Tech., 11, 2257–2277,Short summary
Aerosol layer height (ALH) was retrieved from the OMI 477 nm O2–O2 band and its spatial pattern evaluated over selected cloud-free scenes. We used a neural network approach previously trained and developed. Comparison with CALIOP aerosol level 2 products over urban and industrial pollution in east China shows consistent spatial patterns. In addition, we show the possibility to determine the height of thick aerosol layers released by intensive biomass burning events in South America and Russia.
Igor Veselovskii, Philippe Goloub, Thierry Podvin, Didier Tanre, Arlindo da Silva, Peter Colarco, Patricia Castellanos, Mikhail Korenskiy, Qiaoyun Hu, David N. Whiteman, Daniel Pérez-Ramírez, Patrick Augustin, Marc Fourmentin, and Alexei Kolgotin
Atmos. Meas. Tech., 11, 949–969,Short summary
Observations of multiwavelength Mie–Raman lidar during smoke episode over West Africa are compared with the vertical distribution of aerosol parameters provided by the MERRA-2 model. The values of modeled and observed extinctions at both 355 nm and 532 nm are also rather close. The model predicts significant concentration of dust particles inside the smoke layer. This is supported by a high depolarization ratio of 15 % observed in the center of this layer.
Timo H. Virtanen, Pekka Kolmonen, Larisa Sogacheva, Edith Rodríguez, Giulia Saponaro, and Gerrit de Leeuw
Atmos. Meas. Tech., 11, 925–938,Short summary
We study the collocation mismatch uncertainty related to validating coarse-resolution satellite-based aerosol data against point-like ground based measurements. We use the spatial variability in the satellite data to estimate the upper limit for the uncertainty and study the effect of sampling parameters in the validation. We find that accounting for the collocation mismatch uncertainty increases the fraction of consistent data in the validation.
Lucia T. Deaconu, Fabien Waquet, Damien Josset, Nicolas Ferlay, Fanny Peers, François Thieuleux, Fabrice Ducos, Nicolas Pascal, Didier Tanré, Jacques Pelon, and Philippe Goloub
Atmos. Meas. Tech., 10, 3499–3523,Short summary
This study presents a comparison between active (CALIOP) and passive (POLDER) remote sensing methods, developed for retrieving aerosol above-cloud optical and microphysical properties. Main results show a good agreement when the aerosol microphysics is dominated by fine-mode particles or coarse-mode dust or when the aerosol layer is well separated from the cloud below. The paper is also focused on understanding the differences between the retrievals and the limitations of each method.
Alexander Geiß, Matthias Wiegner, Boris Bonn, Klaus Schäfer, Renate Forkel, Erika von Schneidemesser, Christoph Münkel, Ka Lok Chan, and Rainer Nothard
Atmos. Meas. Tech., 10, 2969–2988,Short summary
Based on measurements with a ceilometer and from an air quality network, the relationship between the mixing layer height (MLH) and near surface concentrations of pollutants was investigated for summer 2014 in Berlin. It was found that the heterogeneity of the concentrations exceeds the differences due to different MLH retrievals. In particular for PM10 it seems to be unrealistic to find correlations between MLH and concentrations representative for an entire metropolitan area in flat terrain.
Andrady, A. L., Aucamp, P. J., Austin, A. T., Bais, A. F., Ballare, C. L., Barnes, P. W., Bernhard, G. H., Bornman, J. F., Caldwell, M. M., de Gruijl, F. R., and Erickson, D. J.: Environmental effects of ozone depletion and its interactions with climate change: 2014 assessment executive summary, Photoch. Photobio. Sci., 14, 14–18, https://doi.org/10.1039/c4pp90042a, 2015.
Arola, A., Kazadzis, S., Lindfors, A., Krotkov, N., Kujanpää, J., Tamminen, J., Bais, A., di Sarra, A., Villaplana, J. M., Brogniez, C., Siani, A. M., Janouch, M., Weihs, P., Webb, A., Koskela, T., Kouremeti, N., Meloni, D., Buchard, V., Auriol, F., Ialongo, I., Staneck, M., Simic, S., Smedley, A., and Kinne, S.: A new approach to correct for absorbing aerosols in OMI UV, Geophys. Res. Lett., 36, L22805, https://doi.org/10.1029/2009gl041137, 2009.
Badosa, J. and Van Weele, M.: Effects of aerosols on UV-index, Tech. Rep. WR-2002-07, KNMI, De Bilt, the Netherlands, 2002.
Badosa, J., Calbó, J., McKenzie, R., Liley, B., González, J.-A., Forgan, B., and Long, C. N.: Two Methods for Retrieving UV Index for All Cloud Conditions from Sky Imager Products or Total SW Radiation Measurements, Photochem. Photobiol., 90, 941–951, https://doi.org/10.1111/php.12272, 2014.
Bais, A. F., Zerefos, C. S., Meleti, C., Ziomas, I. C., and Tourpali, K.: Spectral measurements of solar UVB radiation and its relations to total ozone, SO2, and clouds, J. Geophys. Res.-Atmos., 98, 5199–5204, https://doi.org/10.1029/92jd02904, 1993.
Bais, A. F., Lucas, R. M., Bornman, J. F., Williamson, C. E., Sulzberger, B., Austin, A. T., Wilson, S. R., Andrady, A. L., Bernhard, G., McKenzie, R. L., Aucamp, P. J., Madronich, S., Neale, R. E., Yazar, S., Young, A. R., de Gruijl, F. R., Norval, M., Takizawa, Y., Barnes, P. W., Robson, T. M., Robinson, S. A., Ballaré, C. L., Flint, S. D., Neale, P. J., Hylander, S., Rose, K. C., Wängberg, S. Å., Häder, D. P., Worrest, R. C., Zepp, R. G., Paul, N. D., Cory, R. M., Solomon, K. R., Longstreth, J., Pandey, K. K., Redhwi, H. H., Torikai, A., and Heikkilä, A. M.: Environmental effects of ozone depletion, UV radiation and interactions with climate change: UNEP Environmental Effects Assessment Panel, update 2017, Photoch. Photobio. Sci., 17, 127–179, https://doi.org/10.1039/c7pp90043k, 2018.
Bais, A. F., Bernhard, G., McKenzie, R. L., Aucamp, P. J., Young, P. J., Ilyas, M., Jöckel, P., and Deushi, M.: Ozone–climate interactions and effects on solar ultraviolet radiation, Photoch. Photobio. Sci., 18, 602–640, https://doi.org/10.1039/c8pp90059k, 2019.
Bernhard, G. and Stierle, S.: Trends of UV Radiation in Antarctica, Atmosphere, 11, 795, https://doi.org/10.3390/atmos11080795, 2020.
Bieliński, T.: A Parallax Shift Effect Correction Based on Cloud Height for Geostationary Satellites and Radar Observations, Remote Sens., 12, 365, https://doi.org/10.3390/rs12030365, 2020.
Blumthaler, M. and Ambach, W.: SOLAR UVB-ALBEDO OF VARIOUS SURFACES, Photochem. Photobiol., 48, 85–88, https://doi.org/10.1111/j.1751-1097.1988.tb02790.x, 1988.
Blumthaler, M., Ambach, W., and Ellinger, R.: Increase in solar UV radiation with altitude, J. Photoch. Photobio. B, 39, 130–134, https://doi.org/10.1016/S1011-1344(96)00018-8, 1997.
Boynard, A., Hurtmans, D., Garane, K., Goutail, F., Hadji-Lazaro, J., Koukouli, M. E., Wespes, C., Vigouroux, C., Keppens, A., Pommereau, J.-P., Pazmino, A., Balis, D., Loyola, D., Valks, P., Sussmann, R., Smale, D., Coheur, P.-F., and Clerbaux, C.: Validation of the IASI FORLI/EUMETSAT ozone products using satellite (GOME-2), ground-based (Brewer–Dobson, SAOZ, FTIR) and ozonesonde measurements, Atmos. Meas. Tech., 11, 5125–5152, https://doi.org/10.5194/amt-11-5125-2018, 2018.
Carrer, D., Roujean, J.-L., and Meurey, C.: Comparing Operational MSG/SEVIRI Land Surface Albedo Products From Land SAF With Ground Measurements and MODIS, IEEE T. Geosci. Remote, 48, 1714–1728, https://doi.org/10.1109/TGRS.2009.2034530, 2010.
Cede, A., Herman, J., Richter, A., Krotkov, N., and Burrows, J.: Measurements of nitrogen dioxide total column amounts using a Brewer double spectrophotometer in direct Sun mode, J. Geophys. Res.-Atmos., 111, D05304, https://doi.org/10.1029/2005JD006585, 2006.
Chubarova, N., Zhdanova, Y., and Nezval, Y.: A new parameterization of the UV irradiance altitude dependence for clear-sky conditions and its application in the on-line UV tool over Northern Eurasia, Atmos. Chem. Phys., 16, 11867–11881, https://doi.org/10.5194/acp-16-11867-2016, 2016.
Chubarova, N. E., Pastukhova, A. S., Zhdanova, E. Y., Volpert, E. V., Smyshlyaev, S. P., and Galin, V. Y.: Effects of ozone and clouds on temporal variability of surface UV radiation and UV resources over Northern Eurasia derived from measurements and modeling, Atmosphere, 11, 59, https://doi.org/10.3390/atmos11010059, 2020.
Corr, C. A., Krotkov, N., Madronich, S., Slusser, J. R., Holben, B., Gao, W., Flynn, J., Lefer, B., and Kreidenweis, S. M.: Retrieval of aerosol single scattering albedo at ultraviolet wavelengths at the T1 site during MILAGRO, Atmos. Chem. Phys., 9, 5813–5827, https://doi.org/10.5194/acp-9-5813-2009, 2009.
Czerwińska, A. E., Krzyścin, J. W., Jarosławski, J., and Posyniak, M.: Effects of urban agglomeration on surface-UV doses: a comparison of Brewer measurements in Warsaw and Belsk, Poland, for the period 2013–2015, Atmos. Chem. Phys., 16, 13641–13651, https://doi.org/10.5194/acp-16-13641-2016, 2016.
Dahlback, A.: Dahlback, Measurements of biologically effective UV doses, total ozone abundances, and cloud effects with multichannel, moderate bandwidth filter instruments, Appl. Optics, 35, 6514, https://doi.org/10.1364/AO.35.006514, 1996.
De Bock, V., De Backer, H., Van Malderen, R., Mangold, A., and Delcloo, A.: Relations between erythemal UV dose, global solar radiation, total ozone column and aerosol optical depth at Uccle, Belgium, Atmos. Chem. Phys., 14, 12251–12270, https://doi.org/10.5194/acp-14-12251-2014, 2014.
Derrien, M. and Le Gléau, H.: MSG/SEVIRI cloud mask and type from SAFNWC, Int. J. Remote Sens., 26, 4707–4732, https://doi.org/10.1080/01431160500166128, 2005.
Eleftheratos, K., Kazadzis, S., Zerefos, C. S., Tourpali, K., Meleti, C., Balis, D., Zyrichidou, I., Lakkala, K., Feister, U., Koskela, T., Heikkilä, A., and Karhu, J. M.: Ozone and Spectroradiometric UV Changes in the Past 20 Years over High Latitudes, Atmos.-Ocean, 53, 117–125, https://doi.org/10.1080/07055900.2014.919897, 2015.
Eskes, H., Huijnen, V., Arola, A., Benedictow, A., Blechschmidt, A.-M., Botek, E., Boucher, O., Bouarar, I., Chabrillat, S., Cuevas, E., Engelen, R., Flentje, H., Gaudel, A., Griesfeller, J., Jones, L., Kapsomenakis, J., Katragkou, E., Kinne, S., Langerock, B., Razinger, M., Richter, A., Schultz, M., Schulz, M., Sudarchikova, N., Thouret, V., Vrekoussis, M., Wagner, A., and Zerefos, C.: Validation of reactive gases and aerosols in the MACC global analysis and forecast system, Geosci. Model Dev., 8, 3523–3543, https://doi.org/10.5194/gmd-8-3523-2015, 2015.
Eskes, H. J., Velthoven, P. F. J. V., Valks, P. J. M., and Kelder, H. M.: Assimilation of GOME total-ozone satellite observations in a three-dimensional tracer-transport model, Q. J. Roy. Meteor. Soc., 129, 1663–1681, https://doi.org/10.1256/qj.02.14, 2003.
Eskes, H. J., Wagner, A., Schulz, M., Christophe, Y., Ramonet, M., Basart, S., Benedictow, A., Bennouna, Y., Blechschmidt, A.-M., Chabrillat, S., Clark, H., Cuevas, E., Flentje, H., Hansen, K. M., IM, U., Kapsomenakis, J., Langerock, B., Petersen, K., Richter, A., Sudarchikova, N., Thouret, V., Warneke, T., and Zerefos, C.: Validation report of the cams near-real-time global atmospheric composition service: period September–November 2017, Copernicus Atmosphere Monitoring Service (CAMS) Report, CAMS84_2015SC3_D220.127.116.11_2017SON_V1.pdf, February 2018, available at: https://atmosphere.copernicus.eu/sites/default/files/repository/CAMS84_2015SC3_D18.104.22.168_2017SON_v1_0.pdf (last access: 25 July 2020), 2018.
Feister, U. and Grewe, R.: Spectral Albedo Measurements In The Uv And Visible Region Over Different Types Of Surfaces, Photochem. Photobiol., 62, 736–744, https://doi.org/10.1111/j.1751-1097.1995.tb08723.x, 1995.
Fioletov, V., Kerr, J. B., and Fergusson, A.: The UV Index: Definition, Distribution and Factors Affecting It, C. J. Public Health, 101, I5–I9, https://doi.org/10.1007/bf03405303, 2010.
Fioletov, V. E., Griffioen, E., Kerr, J. B., Wardle, D. I., and Uchino, O.: Influence of volcanic sulfur dioxide on spectral UV irradiance as measured by Brewer spectrophotometers. Geophys. Res. Lett., 25, 1665–1668, 1998.
Fioletov, V. E., Kerr, J. B., McArthur, L. J. B., Wardle, D. I., and Mathews, T. W.: Estimating UV Index Climatology over Canada, J. Appl. Meteorol. Clim., 42, 417–433, https://doi.org/10.1175/1520-0450(2003)042<0417:EUICOC>2.0.CO;2, 2003.
Fioletov, V. E., McArthur, L. J. B., Mathews, T. W., and Marrett, L.: On the relationship between erythemal and vitamin D action spectrum weighted ultraviolet radiation, J. Photoch. Photobio. B, 95, 9–16, https://doi.org/10.1016/j.jphotobiol.2008.11.014, 2009.
Fountoulakis, I., Bais, A. F., Fragkos, K., Meleti, C., Tourpali, K., and Zempila, M. M.: Short- and long-term variability of spectral solar UV irradiance at Thessaloniki, Greece: effects of changes in aerosols, total ozone and clouds, Atmos. Chem. Phys., 16, 2493–2505, https://doi.org/10.5194/acp-16-2493-2016, 2016.
Fountoulakis, I., Zerefos, C. S., Bais, A. F., Kapsomenakis, J., Koukouli, M.-E., Ohkawara, N., Fioletov, V., De Backer, H., Lakkala, K., Karppinen, T., and Webb, A. R.: Twenty-five years of spectral UV-B measurements over Canada, Europe and Japan: Trends and effects from changes in ozone, aerosols, clouds, and surface reflectivity, C. R. Geosci., 350, 393–402, https://doi.org/10.1016/j.crte.2018.07.011, 2018.
Fountoulakis, I., Natsis, A., Siomos, N., Drosoglou, T., and Bais, F. A.: Deriving Aerosol Absorption Properties from Solar Ultraviolet Radiation Spectral Measurements at Thessaloniki, Greece, Remote Sens., 11, 2179, https://doi.org/10.3390/rs11182179, 2019.
Fountoulakis, I., Diémoz, H., Siani, A.-M., Laschewski, G., Filippa, G., Arola, A., Bais, A. F., De Backer, H., Lakkala, K., Webb, A. R., De Bock, V., Karppinen, T., Garane, K., Kapsomenakis, J., Koukouli, M.-E., and Zerefos, C. S.: Solar UV Irradiance in a Changing Climate: Trends in Europe and the Significance of Spectral Monitoring in Italy, Environments, 7, 1, https://doi.org/10.3390/environments7010001, 2020a.
Fountoulakis, I., Diémoz, H., Siani, A. M., Hülsen, G., and Gröbner, J.: Monitoring of solar spectral ultraviolet irradiance in Aosta, Italy, Earth Syst. Sci. Data, 12, 2787–2810, https://doi.org/10.5194/essd-12-2787-2020, 2020b.
Gal, S.: Computing elementary functions: A new approach for achieving high accuracy and good performance, Accurate Scientific Computations, Berlin, Heidelberg, Germany, 1–16, 1986.
Garane, K., Bais, A. F., Kazadzis, S., Kazantzidis, A., and Meleti, C.: Monitoring of UV spectral irradiance at Thessaloniki (1990–2005): data re-evaluation and quality control, Ann. Geophys., 24, 3215–3228, https://doi.org/10.5194/angeo-24-3215-2006, 2006.
Garane, K., Lerot, C., Coldewey-Egbers, M., Verhoelst, T., Koukouli, M. E., Zyrichidou, I., Balis, D. S., Danckaert, T., Goutail, F., Granville, J., Hubert, D., Keppens, A., Lambert, J.-C., Loyola, D., Pommereau, J.-P., Van Roozendael, M., and Zehner, C.: Quality assessment of the Ozone_cci Climate Research Data Package (release 2017) – Part 1: Ground-based validation of total ozone column data products, Atmos. Meas. Tech., 11, 1385–1402, https://doi.org/10.5194/amt-11-1385-2018, 2018.
Garane, K., Koukouli, M.-E., Verhoelst, T., Lerot, C., Heue, K.-P., Fioletov, V., Balis, D., Bais, A., Bazureau, A., Dehn, A., Goutail, F., Granville, J., Griffin, D., Hubert, D., Keppens, A., Lambert, J.-C., Loyola, D., McLinden, C., Pazmino, A., Pommereau, J.-P., Redondas, A., Romahn, F., Valks, P., Van Roozendael, M., Xu, J., Zehner, C., Zerefos, C., and Zimmer, W.: TROPOMI/S5P total ozone column data: global ground-based validation and consistency with other satellite missions, Atmos. Meas. Tech., 12, 5263–5287, https://doi.org/10.5194/amt-12-5263-2019, 2019.
Giles, D. M., Sinyuk, A., Sorokin, M. G., Schafer, J. S., Smirnov, A., Slutsker, I., Eck, T. F., Holben, B. N., Lewis, J. R., Campbell, J. R., Welton, E. J., Korkin, S. V., and Lyapustin, A. I.: Advancements in the Aerosol Robotic Network (AERONET) Version 3 database – automated near-real-time quality control algorithm with improved cloud screening for Sun photometer aerosol optical depth (AOD) measurements, Atmos. Meas. Tech., 12, 169–209, https://doi.org/10.5194/amt-12-169-2019, 2019.
Gratien, A., Nilsson, E., Doussin, J. F., Johnson, M. S., Nielsen, C. J., Stenstrøm, Y., and Picquet-Varrault, B.: UV and IR absorption cross-sections of HCHO, HCDO, and DCDO, J. Phys. Chem. A, 111, 11506–11513, 2007.
Gröbner, J.: Example datasets from PMOD/WRC Davos, Switzerland with the double Brewer B163 and QASUME II compared with the UVIOS model, Atmos. Meas. Tech. (supplement comment), https://doi.org/10.5194/amt-2020-506-CC1, 2021.
Gröbner, J. and Sperfeld, P.: Direct traceability of the portable QASUME irradiance scale to the primary irradiance standard of the PTB, Metrologia, 42, 134–139, https://doi.org/10.1088/0026-1394/42/2/008, 2005.
Gröbner, J., Schreder, J., Kazadzis, S., Bais, A. F., Blumthaler, M., Görts, P., Tax, R., Koskela, T., Seckmeyer, G., Webb, A. R., and Rembges, D.: Traveling reference spectroradiometer for routine quality assurance of spectral solar ultraviolet irradiance measurements, Appl. Optics, 44, 5321-5331, https://doi.org/10.1364/ao.44.005321, 2005.
Gröbner, J., Kröger, I., Egli, L., Hülsen, G., Riechelmann, S., and Sperfeld, P.: The high-resolution extraterrestrial solar spectrum (QASUMEFTS) determined from ground-based solar irradiance measurements, Atmos. Meas. Tech., 10, 3375–3383, https://doi.org/10.5194/amt-10-3375-2017, 2017.
Heikkilä, A., Kaurola, J., Lakkala, K., Karhu, J. M., Kyrö, E., Koskela, T., Engelsen, O., Slaper, H., and Seckmeyer, G.: European UV DataBase (EUVDB) as a repository and quality analyser for solar spectral UV irradiance monitored in Sodankylä, Geosci. Instrum. Method. Data Syst., 5, 333–345, https://doi.org/10.5194/gi-5-333-2016, 2016.
Henderson-Sellers, A. and Wilson, M. F.: Surface albedo data for climatic modeling, Rev. Geophys., 21, 1743–1778, https://doi.org/10.1029/RG021i008p01743, 1983.
Henken, C. C., Schmeits, M. J., Deneke, H., and Roebeling, R. A.: Using MSG-SEVIRI Cloud Physical Properties and Weather Radar Observations for the Detection of Cb/TCu Clouds, J. Appl. Meteorol. Clim., 50, 1587–1600, 2011.
Herman, J. R.: Global increase in UV irradiance during the past 30 years (1979–2008) estimated from satellite data, J. Geophys. Res.-Atmos., 115, D04203, https://doi.org/10.1029/2009jd012219, 2010.
Holick, M. F.: Vitamin D: the underappreciated D-lightful hormone that is important for skeletal and cellular health, Curr. Opin. Endocrinol., 9, 87, https://doi.org/10.1097/00060793-200202000-00011, 2002.
Hülsen, G., Gröbner, J., Bais, A., Blumthaler, M., Disterhoft, P., Johnsen, B., Lantz, K. O., Meleti, C., Schreder, J., Vilaplana Guerrero, J. M., and Ylianttila, L.: Intercomparison of erythemal broadband radiometers calibrated by seven UV calibration facilities in Europe and the USA, Atmos. Chem. Phys., 8, 4865–4875, https://doi.org/10.5194/acp-8-4865-2008, 2008.
Hülsen, G., Gröbner, J., Nevas, S., Sperfeld, P., Egli, L., Porrovecchio, G., and Smid, M.: Traceability of solar UV measurements using the Qasume reference spectroradiometer, Appl. Optics, 55, 7265–7275, https://doi.org/10.1364/AO.55.007265, 2016.
Hülsen, G., Gröbner, J., Bais, A., Blumthaler, M., Diemoz, H., Bolsee, D., Rodríguez, A. D., Fountoulakis, I., Naranen, E., Schreder, J., Stefania, F., and Vilaplana Guerrero, J. M.: Second solar ultraviolet radiometer comparison campaign UVC-II, Metrologia, 57, 035001, https://doi.org/10.1088/1681-7575/ab74e5, 2020.
Johnsen, B., Kjeldstad, B., Aalerud, T. N., Nilsen, L. T., Schreder, J., Blumthaler, M., Bernhard, G., Topaloglou, C., Meinander, O., Bagheri, A., Slusser, J. R., and Davis, J.: Intercomparison and harmonization of UV index measurements from multiband filter radiometers, J. Geophys. Res., 113, D15206, https://doi.org/10.1029/2007JD009731, 2008.
Juzeniene, A., Brekke, P., Dahlback, A., Andersson-Engels, S., Reichrath, J., Moan, K., Holick, M. F., Grant, W. B., and Moan, J.: Solar radiation and human health, Rep. Prog. Phys., 74, 066701, https://doi.org/10.1088/0034-4885/74/6/066701, 2011.
Kato, S. and Marshak, A.: Solar zenith and viewing geometry-dependent errors in satellite retrieved cloud optical thickness: Marine stratocumulus case, J. Geophys. Res., 114, D01202, https://doi.org/10.1029/2008JD010579, 2009.
Kazadzis, S., Bais, A., Balis, D., Kouremeti, N., Zempila, M., Arola, A., Giannakaki, E., Amiridis, V., and Kazantzidis, A.: Spatial and temporal UV irradiance and aerosol variability within the area of an OMI satellite pixel, Atmos. Chem. Phys., 9, 4593–4601, https://doi.org/10.5194/acp-9-4593-2009, 2009a.
Kazadzis, S., Kouremeti, N., Bais, A., Kazantzidis, A., and Meleti, C.: Aerosol forcing efficiency in the UVA region from spectral solar irradiance measurements at an urban environment, Ann. Geophys., 27, 2515–2522, https://doi.org/10.5194/angeo-27-2515-2009, 2009b.
Kazadzis, S., Raptis, P., Kouremeti, N., Amiridis, V., Arola, A., Gerasopoulos, E., and Schuster, G. L.: Aerosol absorption retrieval at ultraviolet wavelengths in a complex environment, Atmos. Meas. Tech., 9, 5997–6011, https://doi.org/10.5194/amt-9-5997-2016, 2016.
Kerr, J. B. and Fioletov, V. E.: Surface ultraviolet radiation, Atmos.-Ocean, 46, 159–184, https://doi.org/10.3137/ao.460108, 2008.
Kerr, J. B., Evans, W. F. J., and Asbridge, I. A.: Recalibration of Dobson Field Spectrophotometers with a Travelling Brewer Spectrophotometer Standard, Atmospheric Ozone, Springer, Dordrecht, the Netherlands, 381–386, 1985.
Kinne, S.: The MACv2 aerosol climatology, Tellus B, 71, 1–21, https://doi.org/10.1080/16000889.2019.1623639, 2019.
Koren, I., Remer, L. A., Kaufman, Y. J., Rudich, Y., and Martins, J. V.: On the twilight zone between clouds and aerosols, Geophys. Res. Lett., 34, L08805, https://doi.org/10.1029/2007GL029253, 2007.
Kosmopoulos, P. G., Kazadzis, S., Taylor, M., Raptis, P. I., Keramitsoglou, I., Kiranoudis, C., and Bais, A. F.: Assessment of surface solar irradiance derived from real-time modelling techniques and verification with ground-based measurements, Atmos. Meas. Tech., 11, 907–924, https://doi.org/10.5194/amt-11-907-2018, 2018.
Kosmopoulos, P. G., Kouroutsidis, D., Papachristopoulou, K., Raptis, P. I., Masoom, A., Saint-Drenan, Y.-M., Blanc, P., Kontoes, C., and Kazadzis, S.: Short-Term Forecasting of Large-Scale Clouds Impact on Downwelling Surface Solar Irradiation, Energies, 13, 6555, https://doi.org/10.3390/en13246555, 2020.
Kreuter, A., Buras, R., Mayer, B., Webb, A., Kift, R., Bais, A., Kouremeti, N., and Blumthaler, M.: Solar irradiance in the heterogeneous albedo environment of the Arctic coast: measurements and a 3-D model study, Atmos. Chem. Phys., 14, 5989–6002, https://doi.org/10.5194/acp-14-5989-2014, 2014.
Krotkov, N. A., Bhartia, P. K., Herman, J. R., Fioletov, V., and Kerr, J.: Satellite estimation of spectral surface UV irradiance in the presence of tropospheric aerosols: 1. Cloud-free case, J. Geophys. Res.-Atmos., 103, 8779–8793, https://doi.org/10.1029/98JD00233, 1998.
Lacaze, R., Smets, B., Trigo, I., Calvet, J.C., Jann, A., Camacho, F., Baret, F., Kidd, R., Defourny, P., Tansey, K., Pacholczyk, P., Balsamo, G., and Szintai, B.: The Copernicus Global Land Service: Present and future, in: Proceedings of the EGU General Assembly, 7–12 April 2013, Vienna, Austria, 4937, 2013.
Lakkala, K., Arola, A., Heikkilä, A., Kaurola, J., Koskela, T., Kyrö, E., Lindfors, A., Meinander, O., Tanskanen, A., Gröbner, J., and Hülsen, G.: Quality assurance of the Brewer spectral UV measurements in Finland, Atmos. Chem. Phys., 8, 3369–3383, https://doi.org/10.5194/acp-8-3369-2008, 2008.
Lakkala, K., Redondas, A., Meinander, O., Thölix, L., Hamari, B., Almansa, A. F., Carreno, V., García, R. D., Torres, C., Deferrari, G., Ochoa, H., Bernhard, G., Sanchez, R., and de Leeuw, G.: UV measurements at Marambio and Ushuaia during 2000–2010, Atmos. Chem. Phys., 18, 16019–16031, https://doi.org/10.5194/acp-18-16019-2018, 2018.
Lakkala, K., Kujanpää, J., Brogniez, C., Henriot, N., Arola, A., Aun, M., Auriol, F., Bais, A. F., Bernhard, G., De Bock, V., Catalfamo, M., Deroo, C., Diémoz, H., Egli, L., Forestier, J.-B., Fountoulakis, I., Garane, K., Garcia, R. D., Gröbner, J., Hassinen, S., Heikkilä, A., Henderson, S., Hülsen, G., Johnsen, B., Kalakoski, N., Karanikolas, A., Karppinen, T., Lamy, K., León-Luis, S. F., Lindfors, A. V., Metzger, J.-M., Minvielle, F., Muskatel, H. B., Portafaix, T., Redondas, A., Sanchez, R., Siani, A. M., Svendby, T., and Tamminen, J.: Validation of the TROPOspheric Monitoring Instrument (TROPOMI) surface UV radiation product, Atmos. Meas. Tech., 13, 6999–7024, https://doi.org/10.5194/amt-13-6999-2020, 2020.
Larkin, A., Haigh, J. D., and Djavidnia, S.: The Effect of Solar UV Irradiance Variations on the Earth's Atmosphere, Space Sci. Rev., 94, 199–214, https://doi.org/10.1023/a:1026771307057, 2000.
Levelt, P. F., Oord, G. H. J. v. d., Dobber, M. R., Malkki, A., Huib, V., Johan de, V., Stammes, P., Lundell, J. O. V., and Saari, H.: The ozone monitoring instrument, IEEE T. Geosci. Remote, 44, 1093–1101, https://doi.org/10.1109/tgrs.2006.872333, 2006.
Levelt, P. F., Joiner, J., Tamminen, J., Veefkind, J. P., Bhartia, P. K., Stein Zweers, D. C., Duncan, B. N., Streets, D. G., Eskes, H., van der A, R., McLinden, C., Fioletov, V., Carn, S., de Laat, J., DeLand, M., Marchenko, S., McPeters, R., Ziemke, J., Fu, D., Liu, X., Pickering, K., Apituley, A., González Abad, G., Arola, A., Boersma, F., Chan Miller, C., Chance, K., de Graaf, M., Hakkarainen, J., Hassinen, S., Ialongo, I., Kleipool, Q., Krotkov, N., Li, C., Lamsal, L., Newman, P., Nowlan, C., Suleiman, R., Tilstra, L. G., Torres, O., Wang, H., and Wargan, K.: The Ozone Monitoring Instrument: overview of 14 years in space, Atmos. Chem. Phys., 18, 5699–5745, https://doi.org/10.5194/acp-18-5699-2018, 2018.
López-Solano, J., Redondas, A., Carlund, T., Rodriguez-Franco, J. J., Diémoz, H., León-Luis, S. F., Hernández-Cruz, B., Guirado-Fuentes, C., Kouremeti, N., Gröbner, J., Kazadzis, S., Carreño, V., Berjón, A., Santana-Díaz, D., Rodríguez-Valido, M., De Bock, V., Moreta, J. R., Rimmer, J., Smedley, A. R. D., Boulkelia, L., Jepsen, N., Eriksen, P., Bais, A. F., Shirotov, V., Vilaplana, J. M., Wilson, K. M., and Karppinen, T.: Aerosol optical depth in the European Brewer Network, Atmos. Chem. Phys., 18, 3885–3902, https://doi.org/10.5194/acp-18-3885-2018, 2018.
Lucas, R., McMichael, T., Smith, W., and Armstrong, B. K.: Solar ultraviolet radiation: global burden of disease from solar ultraviolet radiation, edited by: Prüss-Üstün, A., Zeeb, H., Mathers, C., and Repacholi, M., Environmental burden of disease series, no. 13, World Health Organization, Geneva, Switzerland, 2006.
Lucas, R. M., Byrne, S. N., Correale, J., Ilschner, S., and Hart, P. H.: Ultraviolet radiation, vitamin D and multiple sclerosis, Neurodegenerative Disease Management, 5, 413–424, https://doi.org/10.2217/nmt.15.33, 2015.
Madronich, S.: The Atmosphere and UV-B Radiation at Ground Level, in: Environmental UV Photobiology, edited by: Young, A. R., Moan, J., Björn, L. O., and Nultsch, W., Springer, Boston, MA, USA, https://doi.org/10.1007/978-1-4899-2406-3_1, 1993.
Mayer, B. and Kylling, A.: Technical note: The libRadtran software package for radiative transfer calculations – description and examples of use, Atmos. Chem. Phys., 5, 1855–1877, https://doi.org/10.5194/acp-5-1855-2005, 2005.
Mayer, B., Kylling, A., Madronich, S., and Seckmeyer, G.: Enhanced absorption of UV radiation due to multiple scattering in clouds: Experimental evidence and theoretical explanation, J. Geophys. Res.-Atmos., 103, 31241–31254, https://doi.org/10.1029/98JD02676, 1998.
McKenzie, R., Bernhard, G., Liley, B., Disterhoft, P., Rhodes, S., Bais, A., Morgenstern, O., Newman, P., Oman, L., Brogniez, C., and Simic, S.: Success of Montreal Protocol Demonstrated by Comparing High-Quality UV Measurements with “World Avoided” Calculations from Two Chemistry-Climate Models, Sci. Rep., 9, 12332, https://doi.org/10.1038/s41598-019-48625-z, 2019.
McKenzie, R. L., Aucamp, P. J., Bais, A. F., Björn, L. O., Ilyas, M., and Madronich, S.: Ozone depletion and climate change: impacts on UV radiation, Photoch. Photobio. Sci., 10, 182–198, https://doi.org/10.1039/c0pp90034f, 2011.
Meinander, O., Kazadzis, S., Arola, A., Riihelä, A., Räisänen, P., Kivi, R., Kontu, A., Kouznetsov, R., Sofiev, M., Svensson, J., Suokanerva, H., Aaltonen, V., Manninen, T., Roujean, J.-L., and Hautecoeur, O.: Spectral albedo of seasonal snow during intensive melt period at Sodankylä, beyond the Arctic Circle, Atmos. Chem. Phys., 13, 3793–3810, https://doi.org/10.5194/acp-13-3793-2013, 2013.
MétéoFrance: Algorithm theoretical basis document for cloud products (CMa-PGE01 v3.2, CT-PGE02 v2.2 & CTTH-PGE03 v2.2), Technical Report SAF/NWC/CDOP/MFL/SCI/ATBD/01, MétéoFrance, Paris, France, 2013.
Mok, J., Krotkov, N. A., Torres, O., Jethva, H., Li, Z., Kim, J., Koo, J.-H., Go, S., Irie, H., Labow, G., Eck, T. F., Holben, B. N., Herman, J., Loughman, R. P., Spinei, E., Lee, S. S., Khatri, P., and Campanelli, M.: Comparisons of spectral aerosol single scattering albedo in Seoul, South Korea, Atmos. Meas. Tech., 11, 2295–2311, https://doi.org/10.5194/amt-11-2295-2018, 2018.
Myhre, G. and Myhre, A.: Uncertainties in Radiative Forcing due to Surface Albedo Changes Caused by Land-Use Changes, J. Climate, 16, 1511–1524, https://doi.org/10.1175/1520-0442(2003)016<1511:uirfdt>2.0.co;2, 2003.
NOAA: Data Announcement 88-MGG-02, Digital relief of the surface of the Earth. NOAA, National Geopgysical Data Center, Boulder, Colorado, USA, 1988.
Noël, S., Mieruch, S., Bovensmann, H., and Burrows, J. P.: Preliminary results of GOME-2 water vapour retrievals and first applications in polar regions, Atmos. Chem. Phys., 8, 1519–1529, https://doi.org/10.5194/acp-8-1519-2008, 2008.
Pfeifroth, U., Kothe, S., and Trentmann, J.: Validation report: Meteosat solar surface radiation and effective cloud albedo climate data record (Sarah 2), EUMETSAT SAF CM Validation report with reference number SAF/CM/DWD/VAL/ METEOSAT/HEL, 2.1, https://doi.org/10.5676/EUM_SAF_CM/SARAH/V002, 2016.
Probst, P., Rizzi, R., Tosi, E., Lucarini, V., and Maestri, T.: Total cloud cover from satellite observations and climate models, Atmos. Res., 107, 161–170, https://doi.org/10.1016/j.atmosres.2012.01.005, 2012.
Raptis, I.-P., Kazadzis, S., Eleftheratos, K., Amiridis, V., and Fountoulakis, I.: Single Scattering Albedo's Spectral Dependence Effect on UV Irradiance, Atmosphere, 9, 364, https://doi.org/10.3390/atmos9090364, 2018.
Reda, I. and Andreas, A.: Solar position algorithm for solar radiation applications, NREL Technical Report, NREL/TP-560-34302, Prepared under Task No. WU1D5600, NREL, Colorado, USA, 2008.
Renaud, A., Staehelin, J., Fröhlich, C., Philipona, R., and Heimo, A.: Influence of snow and clouds on erythemal UV radiation: Analysis of Swiss measurements and comparison with models, J. Geophys. Res.-Atmos., 105, 4961–4969, https://doi.org/10.1029/1999JD900160, 2000.
Rimmer, J. S., Redondas, A., and Karppinen, T.: EuBrewNet – A European Brewer network (COST Action ES1207), an overview, Atmos. Chem. Phys., 18, 10347–10353, https://doi.org/10.5194/acp-18-10347-2018, 2018.
Schmalwieser, A. and Siani, A.: Review on Non-Occupational Personal Solar UV Exposure Measurements, Photochem. Photobiol., 94, 900, https://doi.org/10.1111/php.12946, 2018.
Schmalwieser, A. W.: Possibilities to estimate the personal UV radiation exposure from ambient UV radiation measurements, Photoch. Photobio. Sci., 19, 1249–1261, https://doi.org/10.1039/d0pp00182a, 2020.
Schmalwieser, A. W., Gröbner, J., Blumthaler, M., Klotz, B., De Backer, H., Bolsée, D., Werner, R., Tomsic, D., Metelka, L., Eriksen, P., Jepsen, N., Aun, M., Heikkilä, A., Duprat, T., Sandmann, H., Weiss, T., Bais, A., Toth, Z., Siani, A.-M., Vaccaro, L., Diémoz, H., Grifoni, D., Zipoli, G., Lorenzetto, G., Petkov, B. H., di Sarra, A. G., Massen, F., Yousif, C., Aculinin, A. A., den Outer, P., Svendby, T., Dahlback, A., Johnsen, B., Biszczuk-Jakubowska, J., Krzyscin, J., Henriques, D., Chubarova, N., Kolarž, P., Mijatovic, Z., Groselj, D., Pribullova, A., Gonzales, J. R. M., Bilbao, J., Guerrero, J. M. V., Serrano, A., Andersson, S., Vuilleumier, L., Webb, A., and O'Hagan, J.: UV Index monitoring in Europe, Photoch. Photobio. Sci., 16, 1349–1370, https://doi.org/10.1039/c7pp00178a, 2017.
Seckmeyer, G., Erb, R., and Albold, A.: Transmittance of a cloud is wavelength-dependent in the UV-range, Geophys. Res. Lett., 23, 2753–2755, https://doi.org/10.1029/96GL02614, 1996.
Seckmeyer, G., Pissulla, D., Glandorf, M., Henriques, D., Johnsen, B., Webb, A., Siani, A.-M., Bais, A., Kjeldstad, B., Brogniez, C., Lenoble, J., Gardiner, B., Kirsch, P., Koskela, T., Kaurola, J., Uhlmann, B., Slaper, H., Den Outer, P., Janouch, M., Werle, P., Gröbner, J., Mayer, B., De La Casiniere, A., Simic, S., and Carvalho, F.: Variability of UV Irradiance in Europe, Photochem. Photobiol., 84, 172–179, https://doi.org/10.1111/j.1751-1097.2007.00216.x, 2008.
Siani, A. M., Casale, G. R., Diémoz, H., Agnesod, G., Kimlin, M. G., Lang, C. A., and Colosimo, A.: Personal UV exposure in high albedo alpine sites, Atmos. Chem. Phys., 8, 3749–3760, https://doi.org/10.5194/acp-8-3749-2008, 2008.
Slaper, H., Reinen, H. A. J. M., Blumthaler, M., Huber, M., and Kuik, F.: Comparing ground-level spectrally resolved solar UV measurements using various instruments: A technique resolving effects of wavelength shift and slit width, Geophys. Res. Lett., 22, 2721–2724, https://doi.org/10.1029/95gl02824, 1995.
Smedley, A. R. D., Rimmer, J. S., Moore, D., Toumi, R., and Webb, A. R.: Total ozone and surface UV trends in the United Kingdom: 1979–2008, Int. J. Climatol., 32, 338–346, https://doi.org/10.1002/joc.2275, 2012.
Taylor, M., Kosmopoulos, P. G., Kazadzis, S., Keramitsoglou, I., and Kiranoudis, C. T.: Neural network radiative transfer solvers for the generation of high resolution solar irradiance spectra parameterized by cloud and aerosol parameters, J. Quant. Spectrosc. Ra., 168, 176–192, https://doi.org/10.1016/j.jqsrt.2015.08.018, 2016.
Vanicek, K., Frei, T., Litynska, Z., and Schmalwieser, A.: UV-Index for the Public, COST-713 Action, European Union, Brussels, Belgium, ISBN 92-828-8142-3, 2000.
Verdebout, J.: Amethod to generate surface UV radiation maps over Europe using GOME, Meteosat and ancillary geophysical data, J. Geophys. Res.-Atmos., 105, 5049–5058, 2000.
Vitt, R., Laschewski, G., Bais, A. F., Diémoz, H., Fountoulakis, I., Siani, A.-M., and Matzarakis, A.: UV-Index Climatology for Europe Based on Satellite Data, Atmosphere, 11, 727, https://doi.org/10.3390/atmos11070727, 2020.
Webb, A. R. and Engelsen, O.: Ultraviolet Exposure Scenarios: Risks of Erythema from Recommendations on Cutaneous Vitamin D Synthesis, in: Sunlight, Vitamin D and Skin Cancer, edited by: Reichrath, J., Springer New York, New York, NY, USA, 72–85, 2008.
Webb, A. R., Slaper, H., Koepke, P., and Schmalwieser, A. W.: Know Your Standard: Clarifying the CIE Erythema Action Spectrum, Photochem. Photobiol., 87, 483–486, https://doi.org/10.1111/j.1751-1097.2010.00871.x, 2011.
WHO: Global Solar UV Index: A Pratical Guide, No. WHO/SD, Geneva, Switzerland, 2002.
WMO: Report of the WMO Meeting of Experts on UVB Measurements, Data Quality and Standardization of UV Indices, 1994, WMO/TD-No. 625, GAW Report-No. 95, Les Diablerets, Switzerland, 1995.
Zempila, M.-M., Koukouli, M.-E., Bais, A., Fountoulakis, I., Arola, A., Kouremeti, N., and Balis, D.: OMI/Aura UV product validation using NILU-UV ground-based measurements in Thessaloniki, Greece, Atmos. Environ., 140, 283–297, https://doi.org/10.1016/j.atmosenv.2016.06.009, 2016.
Zerefos, C. S., Tourpali, K., Eleftheratos, K., Kazadzis, S., Meleti, C., Feister, U., Koskela, T., and Heikkilä, A.: Evidence of a possible turning point in solar UV-B over Canada, Europe and Japan, Atmos. Chem. Phys., 12, 2469–2477, https://doi.org/10.5194/acp-12-2469-2012, 2012.
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.
Large-scale retrievals of the ultraviolet index (UVI) in real time by exploiting the modern...