Articles | Volume 17, issue 23
https://doi.org/10.5194/acp-17-14353-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-17-14353-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
04 Dec 2017
Research article |
| 04 Dec 2017
| 04 Dec 2017
Sky radiance at a coastline and effects of land and ocean reflectivities
Axel Kreuter
CORRESPONDING AUTHOR
Division for Biomedical Physics, Medical University of Innsbruck,
Innsbruck, Austria
LuftBlick, Earth Observation Technologies, Mutters, Austria
Mario Blumthaler
Division for Biomedical Physics, Medical University of Innsbruck,
Innsbruck, Austria
Martin Tiefengraber
LuftBlick, Earth Observation Technologies, Mutters, Austria
Institute of Atmospheric and Cryospheric Sciences, University of
Innsbruck, Innsbruck, Austria
Richard Kift
School of Earth Atmospheric and Environmental Sciences, University of
Manchester, Manchester, UK
Ann R. Webb
School of Earth Atmospheric and Environmental Sciences, University of
Manchester, Manchester, UK
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Jochen Wagner, Alma Anna Ubele, Verena Schenzinger, and Axel Kreuter
Aerosol Research, 2, 153–159, https://doi.org/10.5194/ar-2-153-2024, https://doi.org/10.5194/ar-2-153-2024, 2024
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In this study, we explored how tiny particles in the air, known as aerosols, have changed over time in two mountainous areas in Austria and Switzerland from 2007 to 2023. By using special instruments that measure sunlight, we tracked these changes and found that the amount of aerosols has been decreasing in both locations. This is important because aerosols can affect both our health and the climate. This work is crucial for understanding air quality trends in mountain environments.
Barbara Klotz, Verena Schenzinger, Michael Schwarzmann, and Axel Kreuter
EGUsphere, https://doi.org/10.5194/egusphere-2023-3130, https://doi.org/10.5194/egusphere-2023-3130, 2024
Preprint withdrawn
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The manuscript compares ground-based measurements of ultraviolet (UV) radiation from 17 German stations with modelled UV maps in which the influence of clouds is taken into account using information from satellite images. While for clear sky conditions the agreement is good, uncertainties increase for cloudy conditions. The issue of representativeness of satellite pixel values versus ground measurements is discussed and an approach to combine measurement and UV map is presented.
Verena Schenzinger, Axel Kreuter, Barbara Klotz, Michael Schwarzmann, and Julian Gröbner
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2023-188, https://doi.org/10.5194/amt-2023-188, 2023
Revised manuscript not accepted
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We present a fast an easy method to incorporate clouds from satellite imagery into a model for calculating surface UV index maps in near-real time. To judge the quality of the model, we compare our results to measurements from ground based detectors. We discuss in detail where variations in either of the values come from and why satellite and ground values might not necessarily be comparable in every situation.
Panagiotis G. Kosmopoulos, Stelios Kazadzis, Alois W. Schmalwieser, Panagiotis I. Raptis, Kyriakoula Papachristopoulou, Ilias Fountoulakis, Akriti Masoom, Alkiviadis F. Bais, Julia Bilbao, Mario Blumthaler, Axel Kreuter, Anna Maria Siani, Kostas Eleftheratos, Chrysanthi Topaloglou, Julian Gröbner, Bjørn Johnsen, Tove M. Svendby, Jose Manuel Vilaplana, Lionel Doppler, Ann R. Webb, Marina Khazova, Hugo De Backer, Anu Heikkilä, Kaisa Lakkala, Janusz Jaroslawski, Charikleia Meleti, Henri Diémoz, Gregor Hülsen, Barbara Klotz, John Rimmer, and Charalampos Kontoes
Atmos. Meas. Tech., 14, 5657–5699, https://doi.org/10.5194/amt-14-5657-2021, https://doi.org/10.5194/amt-14-5657-2021, 2021
Short summary
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Large-scale retrievals of the ultraviolet index (UVI) in real time by exploiting the modern Earth observation data and techniques are capable of forming operational early warning systems that raise awareness among citizens of the health implications of high UVI doses. In this direction a novel UVI operating system, the so-called UVIOS, was introduced for massive outputs, while its performance was tested against ground-based measurements revealing a dependence on the input quality and resolution.
Verena Schenzinger and Axel Kreuter
Atmos. Meas. Tech., 14, 2787–2798, https://doi.org/10.5194/amt-14-2787-2021, https://doi.org/10.5194/amt-14-2787-2021, 2021
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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.
A. Kreuter, R. Buras, B. Mayer, A. Webb, R. Kift, A. Bais, N. Kouremeti, and M. Blumthaler
Atmos. Chem. Phys., 14, 5989–6002, https://doi.org/10.5194/acp-14-5989-2014, https://doi.org/10.5194/acp-14-5989-2014, 2014
A. Kreuter and M. Blumthaler
Atmos. Meas. Tech., 6, 1845–1854, https://doi.org/10.5194/amt-6-1845-2013, https://doi.org/10.5194/amt-6-1845-2013, 2013
A. Kreuter, S. Wuttke, and M. Blumthaler
Atmos. Meas. Tech., 6, 99–103, https://doi.org/10.5194/amt-6-99-2013, https://doi.org/10.5194/amt-6-99-2013, 2013
Yuhang Zhang, Huan Yu, Isabelle De Smedt, Jintai Lin, Nicolas Theys, Michel Van Roozendael, Gaia Pinardi, Steven Compernolle, Ruijing Ni, Fangxuan Ren, Sijie Wang, Lulu Chen, Jos Van Geffen, Mengyao Liu, Alexander M. Cede, Martin Tiefengraber, Alexis Merlaud, Martina M. Friedrich, Andreas Richter, Ankie Piters, Vinod Kumar, Vinayak Sinha, Thomas Wagner, Yongjoo Choi, Hisahiro Takashima, Yugo Kanaya, Hitoshi Irie, Robert Spurr, Wenfu Sun, and Lorenzo Fabris
Atmos. Meas. Tech., 18, 1561–1589, https://doi.org/10.5194/amt-18-1561-2025, https://doi.org/10.5194/amt-18-1561-2025, 2025
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We developed an advanced algorithm for global retrieval of TROPOspheric Monitoring Instrument (TROPOMI) HCHO and NO2 vertical column densities with much improved consistency. Sensitivity tests demonstrate the complexity and nonlinear interactions of auxiliary parameters in the air mass factor calculation. An improved agreement is found with measurements from a global ground-based instrument network. The scientific retrieval provides a useful source of information for studies combining HCHO and NO2.
Carmen González, José Manuel Vilaplana, Alberto Redondas, Javier López-Solano, José María San Atanasio, Richard Kift, Andrew R. D. Smedley, Pavel Babal, Ana Díaz, Nis Jepsen, Guisella Gacitúa, and Antonio Serrano
EGUsphere, https://doi.org/10.5194/egusphere-2025-490, https://doi.org/10.5194/egusphere-2025-490, 2025
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Brewer spectroradiometers are widely used instruments that have been monitoring global solar ultraviolet (UV) irradiance since the 1990s, playing a key role in solar UV research. The uncertainties of these measurements are rarely evaluated even though they are essential to determine the quality of these measurements. In this work, the uncertainty of ten Brewers is estimated using the Monte Carlo method, showing that Brewer’s relative uncertainty is less than 5 % for wavelengths above 300 nm.
Omer Celebi, Andrew R. D. Smedley, Paul J. Connolly, and Ann R. Webb
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-200, https://doi.org/10.5194/amt-2024-200, 2025
Preprint under review for AMT
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Ice crystals have a significant role in weather and climate, but their roughness is not measured which affects how ice crystals scatter sunlight. In our study, we have developed a new way of measuring roughness parameters of ice crystals. By growing crystals in laboratory conditions and creating replicas , we can image them under special imaging tools to measure small features on their surface. Results can be implemented in models to reduce uncertainties in understanding the atmosphere.
Xiaoyi Zhao, Vitali Fioletov, Debora Griffin, Chris McLinden, Ralf Staebler, Cristian Mihele, Kevin Strawbridge, Jonathan Davies, Ihab Abboud, Sum Chi Lee, Alexander Cede, Martin Tiefengraber, and Robert Swap
Atmos. Meas. Tech., 17, 6889–6912, https://doi.org/10.5194/amt-17-6889-2024, https://doi.org/10.5194/amt-17-6889-2024, 2024
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This study explores differences between remote sensing and in situ instruments in terms of their vertical, horizontal, and temporal sampling differences. Understanding and resolving these differences are critical for future analyses linking satellite, ground-based remote sensing, and in situ observations in air quality monitoring. It shows that the meteorological conditions (wind directions, speed, and boundary layer conditions) will strongly affect the agreement between the two measurements.
Jochen Wagner, Alma Anna Ubele, Verena Schenzinger, and Axel Kreuter
Aerosol Research, 2, 153–159, https://doi.org/10.5194/ar-2-153-2024, https://doi.org/10.5194/ar-2-153-2024, 2024
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In this study, we explored how tiny particles in the air, known as aerosols, have changed over time in two mountainous areas in Austria and Switzerland from 2007 to 2023. By using special instruments that measure sunlight, we tracked these changes and found that the amount of aerosols has been decreasing in both locations. This is important because aerosols can affect both our health and the climate. This work is crucial for understanding air quality trends in mountain environments.
Barbara Klotz, Verena Schenzinger, Michael Schwarzmann, and Axel Kreuter
EGUsphere, https://doi.org/10.5194/egusphere-2023-3130, https://doi.org/10.5194/egusphere-2023-3130, 2024
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The manuscript compares ground-based measurements of ultraviolet (UV) radiation from 17 German stations with modelled UV maps in which the influence of clouds is taken into account using information from satellite images. While for clear sky conditions the agreement is good, uncertainties increase for cloudy conditions. The issue of representativeness of satellite pixel values versus ground measurements is discussed and an approach to combine measurement and UV map is presented.
Verena Schenzinger, Axel Kreuter, Barbara Klotz, Michael Schwarzmann, and Julian Gröbner
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2023-188, https://doi.org/10.5194/amt-2023-188, 2023
Revised manuscript not accepted
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We present a fast an easy method to incorporate clouds from satellite imagery into a model for calculating surface UV index maps in near-real time. To judge the quality of the model, we compare our results to measurements from ground based detectors. We discuss in detail where variations in either of the values come from and why satellite and ground values might not necessarily be comparable in every situation.
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, https://doi.org/10.5194/essd-13-4929-2021, https://doi.org/10.5194/essd-13-4929-2021, 2021
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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.
Panagiotis G. Kosmopoulos, Stelios Kazadzis, Alois W. Schmalwieser, Panagiotis I. Raptis, Kyriakoula Papachristopoulou, Ilias Fountoulakis, Akriti Masoom, Alkiviadis F. Bais, Julia Bilbao, Mario Blumthaler, Axel Kreuter, Anna Maria Siani, Kostas Eleftheratos, Chrysanthi Topaloglou, Julian Gröbner, Bjørn Johnsen, Tove M. Svendby, Jose Manuel Vilaplana, Lionel Doppler, Ann R. Webb, Marina Khazova, Hugo De Backer, Anu Heikkilä, Kaisa Lakkala, Janusz Jaroslawski, Charikleia Meleti, Henri Diémoz, Gregor Hülsen, Barbara Klotz, John Rimmer, and Charalampos Kontoes
Atmos. Meas. Tech., 14, 5657–5699, https://doi.org/10.5194/amt-14-5657-2021, https://doi.org/10.5194/amt-14-5657-2021, 2021
Short summary
Short summary
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.
Verena Schenzinger and Axel Kreuter
Atmos. Meas. Tech., 14, 2787–2798, https://doi.org/10.5194/amt-14-2787-2021, https://doi.org/10.5194/amt-14-2787-2021, 2021
Short summary
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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.
Xiaoyi Zhao, Vitali Fioletov, Michael Brohart, Volodya Savastiouk, Ihab Abboud, Akira Ogyu, Jonathan Davies, Reno Sit, Sum Chi Lee, Alexander Cede, Martin Tiefengraber, Moritz Müller, Debora Griffin, and Chris McLinden
Atmos. Meas. Tech., 14, 2261–2283, https://doi.org/10.5194/amt-14-2261-2021, https://doi.org/10.5194/amt-14-2261-2021, 2021
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The Brewer spectrophotometer is one of the main instruments for measurements of atmospheric total column ozone. The global Brewer network largely relies on the world reference instruments (the Brewer triad) operated by Environment and Climate Change Canada since the early 1980s. This study provides an updated assessment (1999–2019) of the reference instrument performance, in terms of random uncertainties and long-term stability.
Elena Spinei, Martin Tiefengraber, Moritz Müller, Manuel Gebetsberger, Alexander Cede, Luke Valin, James Szykman, Andrew Whitehill, Alexander Kotsakis, Fernando Santos, Nader Abbuhasan, Xiaoyi Zhao, Vitali Fioletov, Sum Chi Lee, and Robert Swap
Atmos. Meas. Tech., 14, 647–663, https://doi.org/10.5194/amt-14-647-2021, https://doi.org/10.5194/amt-14-647-2021, 2021
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Plastics are widely used in everyday life and scientific equipment. This paper presents Delrin plastic off-gassing as a function of temperature on the atmospheric measurements of formaldehyde by Pandora spectroscopic instruments. The sealed telescope assembly containing Delrin components emitted large amounts of formaldehyde at 30–45 °C, interfering with the Pandora measurements. These results have a broader implication since electronic products often experience the same temperature.
Tijl Verhoelst, Steven Compernolle, Gaia Pinardi, Jean-Christopher Lambert, Henk J. Eskes, Kai-Uwe Eichmann, Ann Mari Fjæraa, José Granville, Sander Niemeijer, Alexander Cede, Martin Tiefengraber, François Hendrick, Andrea Pazmiño, Alkiviadis Bais, Ariane Bazureau, K. Folkert Boersma, Kristof Bognar, Angelika Dehn, Sebastian Donner, Aleksandr Elokhov, Manuel Gebetsberger, Florence Goutail, Michel Grutter de la Mora, Aleksandr Gruzdev, Myrto Gratsea, Georg H. Hansen, Hitoshi Irie, Nis Jepsen, Yugo Kanaya, Dimitris Karagkiozidis, Rigel Kivi, Karin Kreher, Pieternel F. Levelt, Cheng Liu, Moritz Müller, Monica Navarro Comas, Ankie J. M. Piters, Jean-Pierre Pommereau, Thierry Portafaix, Cristina Prados-Roman, Olga Puentedura, Richard Querel, Julia Remmers, Andreas Richter, John Rimmer, Claudia Rivera Cárdenas, Lidia Saavedra de Miguel, Valery P. Sinyakov, Wolfgang Stremme, Kimberly Strong, Michel Van Roozendael, J. Pepijn Veefkind, Thomas Wagner, Folkard Wittrock, Margarita Yela González, and Claus Zehner
Atmos. Meas. Tech., 14, 481–510, https://doi.org/10.5194/amt-14-481-2021, https://doi.org/10.5194/amt-14-481-2021, 2021
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This paper reports on the ground-based validation of the NO2 data produced operationally by the TROPOMI instrument on board the Sentinel-5 Precursor satellite. Tropospheric, stratospheric, and total NO2 columns are compared to measurements collected from MAX-DOAS, ZSL-DOAS, and PGN/Pandora instruments respectively. The products are found to satisfy mission requirements in general, though negative mean differences are found at sites with high pollution levels. Potential causes are discussed.
Jan-Lukas Tirpitz, Udo Frieß, François Hendrick, Carlos Alberti, Marc Allaart, Arnoud Apituley, Alkis Bais, Steffen Beirle, Stijn Berkhout, Kristof Bognar, Tim Bösch, Ilya Bruchkouski, Alexander Cede, Ka Lok Chan, Mirjam den Hoed, Sebastian Donner, Theano Drosoglou, Caroline Fayt, Martina M. Friedrich, Arnoud Frumau, Lou Gast, Clio Gielen, Laura Gomez-Martín, Nan Hao, Arjan Hensen, Bas Henzing, Christian Hermans, Junli Jin, Karin Kreher, Jonas Kuhn, Johannes Lampel, Ang Li, Cheng Liu, Haoran Liu, Jianzhong Ma, Alexis Merlaud, Enno Peters, Gaia Pinardi, Ankie Piters, Ulrich Platt, Olga Puentedura, Andreas Richter, Stefan Schmitt, Elena Spinei, Deborah Stein Zweers, Kimberly Strong, Daan Swart, Frederik Tack, Martin Tiefengraber, René van der Hoff, Michel van Roozendael, Tim Vlemmix, Jan Vonk, Thomas Wagner, Yang Wang, Zhuoru Wang, Mark Wenig, Matthias Wiegner, Folkard Wittrock, Pinhua Xie, Chengzhi Xing, Jin Xu, Margarita Yela, Chengxin Zhang, and Xiaoyi Zhao
Atmos. Meas. Tech., 14, 1–35, https://doi.org/10.5194/amt-14-1-2021, https://doi.org/10.5194/amt-14-1-2021, 2021
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Multi-axis differential optical absorption spectroscopy (MAX-DOAS) is a ground-based remote sensing measurement technique that derives atmospheric aerosol and trace gas vertical profiles from skylight spectra. In this study, consistency and reliability of MAX-DOAS profiles are assessed by applying nine different evaluation algorithms to spectral data recorded during an intercomparison campaign in the Netherlands and by comparing the results to colocated supporting observations.
Gaia Pinardi, Michel Van Roozendael, François Hendrick, Nicolas Theys, Nader Abuhassan, Alkiviadis Bais, Folkert Boersma, Alexander Cede, Jihyo Chong, Sebastian Donner, Theano Drosoglou, Anatoly Dzhola, Henk Eskes, Udo Frieß, José Granville, Jay R. Herman, Robert Holla, Jari Hovila, Hitoshi Irie, Yugo Kanaya, Dimitris Karagkiozidis, Natalia Kouremeti, Jean-Christopher Lambert, Jianzhong Ma, Enno Peters, Ankie Piters, Oleg Postylyakov, Andreas Richter, Julia Remmers, Hisahiro Takashima, Martin Tiefengraber, Pieter Valks, Tim Vlemmix, Thomas Wagner, and Folkard Wittrock
Atmos. Meas. Tech., 13, 6141–6174, https://doi.org/10.5194/amt-13-6141-2020, https://doi.org/10.5194/amt-13-6141-2020, 2020
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We validate several GOME-2 and OMI tropospheric NO2 products with 23 MAX-DOAS and 16 direct sun instruments distributed worldwide, highlighting large horizontal inhomogeneities at several sites affecting the validation results. We propose a method for quantification and correction. We show the application of such correction reduces the satellite underestimation in almost all heterogeneous cases, but a negative bias remains over the MAX-DOAS and direct sun network ensemble for both satellites.
Hannah L. Walker, Mathew R. Heal, Christine F. Braban, Mhairi Coyle, Sarah R. Leeson, Ivan Simmons, Matthew R. Jones, Richard Kift, and Marsailidh M. Twigg
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-219, https://doi.org/10.5194/amt-2020-219, 2020
Revised manuscript not accepted
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Quantifying local photolysis rates are critical to understanding local air quality. We present the first year of a long-term filter radiometer measurement dataset in the UK (Auchencorth Moss, SE Scotland), and demonstrate the potential application of this data to account for variations in local meteorology (e.g. clouds and aerosols) in atmospheric models, which otherwise increase computational cost. The scientific and policy value of these measurements are also emphasised.
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, https://doi.org/10.5194/amt-13-2169-2020, https://doi.org/10.5194/amt-13-2169-2020, 2020
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In September 2016, 36 spectrometers from 24 institutes measured a number of key atmospheric pollutants during an instrument intercomparison campaign (CINDI-2) at Cabauw, the Netherlands. Here we report on the outcome of this intercomparison exercise. The three major goals were to characterise the differences between the participating instruments, to define a robust methodology for performance assessment, and to contribute to the harmonisation of the measurement settings and retrieval methods.
Xiaoyi Zhao, Debora Griffin, Vitali Fioletov, Chris McLinden, Alexander Cede, Martin Tiefengraber, Moritz Müller, Kristof Bognar, Kimberly Strong, Folkert Boersma, Henk Eskes, Jonathan Davies, Akira Ogyu, and Sum Chi Lee
Atmos. Meas. Tech., 13, 2131–2159, https://doi.org/10.5194/amt-13-2131-2020, https://doi.org/10.5194/amt-13-2131-2020, 2020
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Pandora NO2 measurements made at three sites located in the Toronto area are used to evaluate the TROPOspheric Monitoring Instrument (TROPOMI) NO2 data products, including standard NO2 and research data developed using a high-resolution regional air quality forecast model. TROPOMI pixels located upwind and downwind from the Pandora sites were analyzed by a new wind-based validation method, which revealed the spatial patterns of local and transported emissions and regional air quality changes.
Laura M. Judd, Jassim A. Al-Saadi, Scott J. Janz, Matthew G. Kowalewski, R. Bradley Pierce, James J. Szykman, Lukas C. Valin, Robert Swap, Alexander Cede, Moritz Mueller, Martin Tiefengraber, Nader Abuhassan, and David Williams
Atmos. Meas. Tech., 12, 6091–6111, https://doi.org/10.5194/amt-12-6091-2019, https://doi.org/10.5194/amt-12-6091-2019, 2019
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In 2017, an airborne mapping spectrometer (GeoTASO) was used to observe high-resolution column densities of nitrogen dioxide (NO2) over the western shore of Lake Michigan and the Los Angeles Basin. These data were used to simulate the spatial resolution of current and future satellite NO2 retrievals to evaluate the impact of pixel size on comparisons to ground-based observations in urban areas. As spatial resolution improves, the sensitivity to more heterogeneously polluted scenes increases.
Xiaoyi Zhao, Debora Griffin, Vitali Fioletov, Chris McLinden, Jonathan Davies, Akira Ogyu, Sum Chi Lee, Alexandru Lupu, Michael D. Moran, Alexander Cede, Martin Tiefengraber, and Moritz Müller
Atmos. Chem. Phys., 19, 10619–10642, https://doi.org/10.5194/acp-19-10619-2019, https://doi.org/10.5194/acp-19-10619-2019, 2019
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New nitrogen dioxide (NO2) retrieval algorithms are developed for Pandora zenith-sky measurements. A column-to-surface conversion look-up table was produced for the Pandora instruments; therefore, quick and practical Pandora-based surface NO2 concentration data can be obtained for air quality monitoring purposes. It is demonstrated that the surface NO2 concentration is controlled not only by the planetary boundary layer height but also by both boundary layer dynamics and photochemistry.
Tim Bösch, Vladimir Rozanov, Andreas Richter, Enno Peters, Alexei Rozanov, Folkard Wittrock, Alexis Merlaud, Johannes Lampel, Stefan Schmitt, Marijn de Haij, Stijn Berkhout, Bas Henzing, Arnoud Apituley, Mirjam den Hoed, Jan Vonk, Martin Tiefengraber, Moritz Müller, and John Philip Burrows
Atmos. Meas. Tech., 11, 6833–6859, https://doi.org/10.5194/amt-11-6833-2018, https://doi.org/10.5194/amt-11-6833-2018, 2018
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A new MAX-DOAS profiling algorithm for aerosols and trace
gases was developed.
The performance of this novel algorithm was tested with the help of
synthetic data and measurements from the CINDI-2 campaign in Cabauw, the
Netherlands, in 2016.
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, https://doi.org/10.5194/acp-18-13481-2018, https://doi.org/10.5194/acp-18-13481-2018, 2018
Elena Spinei, Andrew Whitehill, Alan Fried, Martin Tiefengraber, Travis N. Knepp, Scott Herndon, Jay R. Herman, Moritz Müller, Nader Abuhassan, Alexander Cede, Dirk Richter, James Walega, James Crawford, James Szykman, Lukas Valin, David J. Williams, Russell Long, Robert J. Swap, Youngjae Lee, Nabil Nowak, and Brett Poche
Atmos. Meas. Tech., 11, 4943–4961, https://doi.org/10.5194/amt-11-4943-2018, https://doi.org/10.5194/amt-11-4943-2018, 2018
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Formaldehyde is toxic to humans and is formed in the atmosphere in the presence of air pollution, but the measurements are sparse. Pandonia Global Network instruments measure total formaldehyde column from the surface to the top of troposphere and will be widely available. This study compared formaldehyde Pandora columns with the surface and aircraft-integrated columns near Seoul, South Korea. Relatively good agreement was observed between the three datasets with some overestimation by Pandora.
Andrew R. D. Smedley, John S. Rimmer, and Ann R. Webb
Atmos. Meas. Tech., 10, 4697–4704, https://doi.org/10.5194/amt-10-4697-2017, https://doi.org/10.5194/amt-10-4697-2017, 2017
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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.
Luca Egli, Julian Gröbner, Gregor Hülsen, Luciano Bachmann, Mario Blumthaler, Jimmy Dubard, Marina Khazova, Richard Kift, Kees Hoogendijk, Antonio Serrano, Andrew Smedley, and José-Manuel Vilaplana
Atmos. Meas. Tech., 9, 1553–1567, https://doi.org/10.5194/amt-9-1553-2016, https://doi.org/10.5194/amt-9-1553-2016, 2016
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Array spectroradiometers are small, light, robust and cost-effective instruments, and are increasingly used for atmospheric measurements. The quality of array spectroradiometers is assessed for the reliable quantification of ultraviolet radiation (UV) in order to monitor the exposure of UV radiation to human health. The study shows that reliable UV measurements with these instruments are limited for observations around noon and show large biases in the morning and evening.
A. Kreuter, R. Buras, B. Mayer, A. Webb, R. Kift, A. Bais, N. Kouremeti, and M. Blumthaler
Atmos. Chem. Phys., 14, 5989–6002, https://doi.org/10.5194/acp-14-5989-2014, https://doi.org/10.5194/acp-14-5989-2014, 2014
A. Kreuter and M. Blumthaler
Atmos. Meas. Tech., 6, 1845–1854, https://doi.org/10.5194/amt-6-1845-2013, https://doi.org/10.5194/amt-6-1845-2013, 2013
A. Kreuter, S. Wuttke, and M. Blumthaler
Atmos. Meas. Tech., 6, 99–103, https://doi.org/10.5194/amt-6-99-2013, https://doi.org/10.5194/amt-6-99-2013, 2013
Related subject area
Subject: Radiation | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
First Reported Detection of a Winter Continental Gamma-Ray Glow in Europe
Broadband and filter radiometers at Ross Island, Antarctica: detection of cloud ice phase versus liquid water influences on shortwave and longwave radiation
Tethered balloon-borne observations of thermal-infrared irradiance and cooling rate profiles in the Arctic atmospheric boundary layer
Assessing the cloud radiative bias at Macquarie Island in the ACCESS-AM2 model
Surface energy balance fluxes in a suburban area of Beijing: energy partitioning variability
Effects of variable ice–ocean surface properties and air mass transformation on the Arctic radiative energy budget
Airborne observations of the surface cloud radiative effect during different seasons over sea ice and open ocean in the Fram Strait
Assessment of spectral UV radiation at Marambio Base, Antarctic Peninsula
Parameterization of downward long-wave radiation based on long-term baseline surface radiation measurements in China
An assessment of land energy balance over East Asia from multiple lines of evidence and the roles of the Tibet Plateau, aerosols, and clouds
Ozone, DNA-active UV radiation, and cloud changes for the near-global mean and at high latitudes due to enhanced greenhouse gas concentrations
In situ observation of warm atmospheric layer and the heat contribution of suspended dust over the Tarim Basin
Eight-year variations in atmospheric radiocesium in Fukushima city
Variability and trends in surface solar spectral ultraviolet irradiance in Italy: on the influence of geopotential height and lower-stratospheric ozone
Fifty-six years of surface solar radiation and sunshine duration over São Paulo, Brazil: 1961–2016
Changes in the surface broadband shortwave radiation budget during the 2017 eclipse
Reassessment of shortwave surface cloud radiative forcing in the Arctic: consideration of surface-albedo–cloud interactions
Deposition of brown carbon onto snow: changes in snow optical and radiative properties
Solar UV radiation measurements in Marambio, Antarctica, during years 2017–2019
A revisiting of the parametrization of downward longwave radiation in summer over the Tibetan Plateau based on high-temporal-resolution measurements
Trends in surface radiation and cloud radiative effect at four Swiss sites for the 1996–2015 period
Can downwelling far-infrared radiances over Antarctica be estimated from mid-infrared information?
Measurements of spectral irradiance during the solar eclipse of 21 August 2017: reassessment of the effect of solar limb darkening and of changes in total ozone
UV measurements at Marambio and Ushuaia during 2000–2010
On the suitability of current atmospheric reanalyses for regional warming studies over China
A long-term time series of global and diffuse photosynthetically active radiation in the Mediterranean: interannual variability and cloud effects
Long-term series and trends in surface solar radiation in Athens, Greece
Reconstruction and analysis of erythemal UV radiation time series from Hradec Králové (Czech Republic) over the past 50 years
Trends in erythemal doses at the Polish Polar Station, Hornsund, Svalbard based on the homogenized measurements (1996–2016) and reconstructed data (1983–1995)
Effects of vernal equinox solar eclipse on temperature and wind direction in Switzerland
Impact of aerosols and clouds on decadal trends in all-sky solar radiation over the Netherlands (1966–2015)
Contributions of surface solar radiation and precipitation to the spatiotemporal patterns of surface and air warming in China from 1960 to 2003
Multiresolution analysis of the spatiotemporal variability in global radiation observed by a dense network of 99 pyranometers
Validation of satellite-based noontime UVI with NDACC ground-based instruments: influence of topography, environment and satellite overpass time
Is global dimming and brightening in Japan limited to urban areas?
The climatology of planetary boundary layer height in China derived from radiosonde and reanalysis data
Detection of dimming/brightening in Italy from homogenized all-sky and clear-sky surface solar radiation records and underlying causes (1959–2013)
Comparison of land–atmosphere interaction at different surface types in the mid- to lower reaches of the Yangtze River valley
Spectral optical layer properties of cirrus from collocated airborne measurements and simulations
Local short-term variability in solar irradiance
The contrasting roles of water and dust in controlling daily variations in radiative heating of the summertime Saharan heat low
Global dimming and urbanization: did stronger negative SSR trends collocate with regions of population growth?
Short- and long-term variability of spectral solar UV irradiance at Thessaloniki, Greece: effects of changes in aerosols, total ozone and clouds
On the progress of the 2015–2016 El Niño event
Role of radiatively forced temperature changes in enhanced semi-arid warming in the cold season over east Asia
Assessment of long-term WRF–CMAQ simulations for understanding direct aerosol effects on radiation "brightening" in the United States
Comparison of OMI UV observations with ground-based measurements at high northern latitudes
Characterisation of J(O1D) at Cape Grim 2000–2005
On the scaling of the solar incident flux
Analysis of actinic flux profiles measured from an ozonesonde balloon
Jakub Šlegl, Zbyněk Sokol, Petr Pešice, Ronald Langer, Igor Strhárský, Jana Popová, Martin Kákona, Iva Ambrožová, and Ondřej Ploc
EGUsphere, https://doi.org/10.5194/egusphere-2024-3075, https://doi.org/10.5194/egusphere-2024-3075, 2024
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We observed the first-ever gamma-ray glow from a winter thunderstorm in Europe. Typically, these high-energy radiation events are linked to strong electric fields, but we found a surprisingly weak field at ground level. This suggests that the electric field higher up in the cloud plays a key role. Using advanced instruments, we gained new insights into how thunderstorms produce radiation, especially under rare winter conditions. This challenges existing theories.
Kristopher Scarci, Ryan C. Scott, Madison L. Ghiz, Andrew M. Vogelmann, and Dan Lubin
Atmos. Chem. Phys., 24, 6681–6697, https://doi.org/10.5194/acp-24-6681-2024, https://doi.org/10.5194/acp-24-6681-2024, 2024
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We demonstrate what can be learned about an Antarctic region's climate from basic atmospheric irradiance measurements made by broadband and filter radiometers, instruments suitable for deployment at very remote sites, assisted by meteorological reanalysis and satellite remote sensing. Analysis of shortwave and longwave irradiance reveals subtle contrasts between meteorological regimes favoring cloud ice versus liquid water, relevant to onset versus inhibition of surface melt over ice shelves.
Michael Lonardi, Elisa F. Akansu, André Ehrlich, Mauro Mazzola, Christian Pilz, Matthew D. Shupe, Holger Siebert, and Manfred Wendisch
Atmos. Chem. Phys., 24, 1961–1978, https://doi.org/10.5194/acp-24-1961-2024, https://doi.org/10.5194/acp-24-1961-2024, 2024
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Profiles of thermal-infrared irradiance were measured at two Arctic sites. The presence or lack of clouds influences the vertical structure of these observations. In particular, the cloud top region is a source of radiative energy that can promote cooling and mixing in the cloud layer. Simulations are used to further characterize how the amount of water in the cloud modifies this forcing. A case study additionally showcases the evolution of the radiation profiles in a dynamic atmosphere.
Zhangcheng Pei, Sonya L. Fiddes, W. John R. French, Simon P. Alexander, Marc D. Mallet, Peter Kuma, and Adrian McDonald
Atmos. Chem. Phys., 23, 14691–14714, https://doi.org/10.5194/acp-23-14691-2023, https://doi.org/10.5194/acp-23-14691-2023, 2023
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In this paper, we use ground-based observations to evaluate a climate model and a satellite product in simulating surface radiation and investigate how radiation biases are influenced by cloud properties over the Southern Ocean. We find that significant radiation biases exist in both the model and satellite. The cloud fraction and cloud occurrence play an important role in affecting radiation biases. We suggest further development for the model and satellite using ground-based observations.
Junxia Dou, Sue Grimmond, Shiguang Miao, Bei Huang, Huimin Lei, and Mingshui Liao
Atmos. Chem. Phys., 23, 13143–13166, https://doi.org/10.5194/acp-23-13143-2023, https://doi.org/10.5194/acp-23-13143-2023, 2023
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Multi-timescale variations in surface energy fluxes in a suburb of Beijing are analyzed using 16-month observations. Compared to previous suburban areas, this study site has larger seasonal variability in energy partitioning, and summer and winter Bowen ratios are at the lower and higher end of those at other suburban sites, respectively. Our analysis indicates that precipitation, irrigation, crop/vegetation growth activity, and land use/cover all play critical roles in energy partitioning.
Manfred Wendisch, Johannes Stapf, Sebastian Becker, André Ehrlich, Evelyn Jäkel, Marcus Klingebiel, Christof Lüpkes, Michael Schäfer, and Matthew D. Shupe
Atmos. Chem. Phys., 23, 9647–9667, https://doi.org/10.5194/acp-23-9647-2023, https://doi.org/10.5194/acp-23-9647-2023, 2023
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Atmospheric radiation measurements have been conducted during two field campaigns using research aircraft. The data are analyzed to see if the near-surface air in the Arctic is warmed or cooled if warm–humid air masses from the south enter the Arctic or cold–dry air moves from the north from the Arctic to mid-latitude areas. It is important to study these processes and to check if climate models represent them well. Otherwise it is not possible to reliably forecast the future Arctic climate.
Sebastian Becker, André Ehrlich, Michael Schäfer, and Manfred Wendisch
Atmos. Chem. Phys., 23, 7015–7031, https://doi.org/10.5194/acp-23-7015-2023, https://doi.org/10.5194/acp-23-7015-2023, 2023
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This study analyses the variability of the warming or cooling effect of clouds on the Arctic surface. Therefore, aircraft radiation measurements were performed over sea ice and open ocean during three seasonally different campaigns. It is found that clouds cool the open-ocean surface most strongly in summer. Over sea ice, clouds warm the surface in spring but have a neutral effect in summer. Due to the variable sea ice extent, clouds warm the surface during spring but cool it during late summer.
Klára Čížková, Kamil Láska, Ladislav Metelka, and Martin Staněk
Atmos. Chem. Phys., 23, 4617–4636, https://doi.org/10.5194/acp-23-4617-2023, https://doi.org/10.5194/acp-23-4617-2023, 2023
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The study deals with ultraviolet (UV) radiation in southern polar conditions, where ozone depletion occurs each spring. A 10-year-long time series of UV spectra from Marambio Base, Antarctic Peninsula, has been studied, with a focus on the changes of UV radiation at different wavelengths and the effects of atmospheric and terrestrial variables like ozone, solar elevation, or cloudiness. At the very short wavelengths, the effect of ozone and its deficiency was clearly observed.
Junli Yang, Jianglin Hu, Qiying Chen, and Weijun Quan
Atmos. Chem. Phys., 23, 4419–4430, https://doi.org/10.5194/acp-23-4419-2023, https://doi.org/10.5194/acp-23-4419-2023, 2023
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Downward long-wave radiation (DLR) affects energy exchange between the land surface and the atmosphere, while it is seldom observed at conventional radiation stations. Therefore, parameterization of DLR based on the near-surface meteorological variables provides a chance to estimate the DLR over most meteorological stations. This work established three parameterizations suited to estimating the DLR over China by using the measurements from the CBSRN with an accuracy of ~6.1 %.
Qiuyan Wang, Hua Zhang, Su Yang, Qi Chen, Xixun Zhou, Bing Xie, Yuying Wang, Guangyu Shi, and Martin Wild
Atmos. Chem. Phys., 22, 15867–15886, https://doi.org/10.5194/acp-22-15867-2022, https://doi.org/10.5194/acp-22-15867-2022, 2022
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The present-day land energy balance over East Asia is estimated for the first time. Results indicate that high aerosol loadings, clouds, and the Tibet Plateau (TP) over East Asia play vital roles in the shortwave budgets, while the TP is responsible for the longwave budgets during this regional energy budget assessment. This study provides a perspective to understand fully how the potential factors influence the diversifying regional energy budget assessments.
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, Irina Petropavlovskikh, Kaisa Lakkala, and Kostas Douvis
Atmos. Chem. Phys., 22, 12827–12855, https://doi.org/10.5194/acp-22-12827-2022, https://doi.org/10.5194/acp-22-12827-2022, 2022
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We present the future evolution of DNA-active ultraviolet (UV) radiation in view of increasing greenhouse gases (GHGs) and decreasing ozone depleting substances (ODSs). It is shown that DNA-active UV radiation might increase after 2050 between 50° N–50° S due to GHG-induced reductions in clouds and ozone, something that is likely not to happen at high latitudes, where DNA-active UV radiation will continue its downward trend mainly due to stratospheric ozone recovery from the reduction in ODSs.
Chenglong Zhou, Yuzhi Liu, Qingzhe Zhu, Qing He, Tianliang Zhao, Fan Yang, Wen Huo, Xinghua Yang, and Ali Mamtimin
Atmos. Chem. Phys., 22, 5195–5207, https://doi.org/10.5194/acp-22-5195-2022, https://doi.org/10.5194/acp-22-5195-2022, 2022
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Based on the radiosonde observations, an anomalously warm layer is measured at altitudes between 500 and 300 hPa over the Tarim Basin (TB) with an average intensity of 2.53 and 1.39 K in the spring and summer, respectively. The heat contributions of dust to this anomalously warm atmospheric layer in spring and summer were 13.77 and 10.25 %, respectively. Topographically, the TB is adjacent to the Tibetan Plateau; we propose the concept of the Tibetan heat source’s northward extension.
Akira Watanabe, Mizuo Kajino, Kazuhiko Ninomiya, Yoshitaka Nagahashi, and Atsushi Shinohara
Atmos. Chem. Phys., 22, 675–692, https://doi.org/10.5194/acp-22-675-2022, https://doi.org/10.5194/acp-22-675-2022, 2022
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This study summarizes continuous measurements of surface air concentrations and deposition of radiocesium in Fukushima city over 8 years after the Fukushima nuclear accident. The concentration in the city was high in winter and low in summer (inverse of the forest area). The decreasing trends were much faster in the earlier stage, probably because dissolved cesium discharged faster from the local environment. Biotite might play a key role in circulation of particulate cesium in Fukushima city.
Ilias Fountoulakis, Henri Diémoz, Anna Maria Siani, Alcide di Sarra, Daniela Meloni, and Damiano M. Sferlazzo
Atmos. Chem. Phys., 21, 18689–18705, https://doi.org/10.5194/acp-21-18689-2021, https://doi.org/10.5194/acp-21-18689-2021, 2021
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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).
Marcia Akemi Yamasoe, Nilton Manuel Évora Rosário, Samantha Novaes Santos Martins Almeida, and Martin Wild
Atmos. Chem. Phys., 21, 6593–6603, https://doi.org/10.5194/acp-21-6593-2021, https://doi.org/10.5194/acp-21-6593-2021, 2021
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Spatio-temporal disparity to assess global dimming and brightening phenomena has been a critical topic. For instance, few studies addressed surface solar irradiation (SSR) long-term trend in South America. In this study, SSR, sunshine duration (SD) and the diurnal temperature range (DTR) are analysed for São Paulo, Brazil. We found a dimming phase, identified by SSR, SD and DTR, extending till 1983. Then, while SSR is still declining, consistent with cloud increasing, SD and DTR are increasing.
Guoyong Wen, Alexander Marshak, Si-Chee Tsay, Jay Herman, Ukkyo Jeong, Nader Abuhassan, Robert Swap, and Dong Wu
Atmos. Chem. Phys., 20, 10477–10491, https://doi.org/10.5194/acp-20-10477-2020, https://doi.org/10.5194/acp-20-10477-2020, 2020
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We combine the ground-based observations and radiative transfer model to quantify the impact of the 2017 solar eclipse on surface shortwave irradiation reduction. We find that the eclipse caused local reductions of time-averaged surface flux of about 379 W m-2 (50 %) and 329 W m-2 (46 %) during the ~ 3 h course of the eclipse at the Casper and Columbia sites, respectively. We estimate that the Moon’s shadow caused a reduction of approximately 7 %–8 % in global average surface broadband SW radiation.
Johannes Stapf, André Ehrlich, Evelyn Jäkel, Christof Lüpkes, and Manfred Wendisch
Atmos. Chem. Phys., 20, 9895–9914, https://doi.org/10.5194/acp-20-9895-2020, https://doi.org/10.5194/acp-20-9895-2020, 2020
Nicholas D. Beres, Deep Sengupta, Vera Samburova, Andrey Y. Khlystov, and Hans Moosmüller
Atmos. Chem. Phys., 20, 6095–6114, https://doi.org/10.5194/acp-20-6095-2020, https://doi.org/10.5194/acp-20-6095-2020, 2020
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Brown carbon (BrC) aerosol can be produced by the smoldering combustion of peat, a wildland fuel common at high latitude, often adjacent to the cryosphere. However, little is known about how BrC deposition onto snow changes snow optical and radiative properties. Here, we artificially deposited BrC onto natural snow surfaces, monitored changes of the spectral surface albedo, characterized optical properties of deposited aerosol, and compared to modeled values of albedo and radiative forcing.
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, https://doi.org/10.5194/acp-20-6037-2020, https://doi.org/10.5194/acp-20-6037-2020, 2020
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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.
Mengqi Liu, Xiangdong Zheng, Jinqiang Zhang, and Xiangao Xia
Atmos. Chem. Phys., 20, 4415–4426, https://doi.org/10.5194/acp-20-4415-2020, https://doi.org/10.5194/acp-20-4415-2020, 2020
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This study uses 1 min radiation and lidar measurements at three stations over the Tibetan Plateau (TP) to parametrize downward longwave radiation (DLR) during summer months. Clear-sky DLR can be estimated from the best parametrization with a RMSE of 3.8 W m-2 and R2 > 0.98. Additionally cloud base height under overcast conditions is shown to play an important role in cloudy DLR parametrization, which is considered in the locally calibrated parametrization over the TP for the first time.
Stephan Nyeki, Stefan Wacker, Christine Aebi, Julian Gröbner, Giovanni Martucci, and Laurent Vuilleumier
Atmos. Chem. Phys., 19, 13227–13241, https://doi.org/10.5194/acp-19-13227-2019, https://doi.org/10.5194/acp-19-13227-2019, 2019
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The trends of meteorological parameters and surface downward shortwave radiation (DSR) and downward longwave radiation (DLR) were analysed at four stations (between 370 and 3580 m a. s. l.) in Switzerland for the 1996–2015 period. Trends in DSR and DLR were positive during cloudy as well as clear conditions. The trend due to the influence of clouds decreased in magnitude, which implies a reduction in cloud cover and/or a change towards a different cloud type over the four Swiss sites.
Christophe Bellisario, Helen E. Brindley, Simon F. B. Tett, Rolando Rizzi, Gianluca Di Natale, Luca Palchetti, and Giovanni Bianchini
Atmos. Chem. Phys., 19, 7927–7937, https://doi.org/10.5194/acp-19-7927-2019, https://doi.org/10.5194/acp-19-7927-2019, 2019
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We explore the possibility of inferring far-infrared downwelling radiances from mid-infrared observations to better constrain radiation schemes in climate models. Our results imply that while it is feasible to use this type of approach, the quality of the extension will be strongly dependent on the noise characteristics of the observations and on the accurate characterisation of the atmospheric state.
Germar Bernhard and Boyan Petkov
Atmos. Chem. Phys., 19, 4703–4719, https://doi.org/10.5194/acp-19-4703-2019, https://doi.org/10.5194/acp-19-4703-2019, 2019
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Solar radiation at ultraviolet, visible, and infrared wavelengths was measured during the total solar eclipse of 21 August 2017. Data were used to study the wavelength-dependent changes of solar radiation at Earth’s surface and to validate parameterizations of solar limb darkening (LD), which describes the change in the Sun’s brightness between its center and its edge. The study highlights the importance of the LD effect when calculating total ozone and aerosol optical depth during an eclipse.
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, https://doi.org/10.5194/acp-18-16019-2018, https://doi.org/10.5194/acp-18-16019-2018, 2018
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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.
Chunlüe Zhou, Yanyi He, and Kaicun Wang
Atmos. Chem. Phys., 18, 8113–8136, https://doi.org/10.5194/acp-18-8113-2018, https://doi.org/10.5194/acp-18-8113-2018, 2018
Pamela Trisolino, Alcide di Sarra, Fabrizio Anello, Carlo Bommarito, Tatiana Di Iorio, Daniela Meloni, Francesco Monteleone, Giandomenico Pace, Salvatore Piacentino, and Damiano Sferlazzo
Atmos. Chem. Phys., 18, 7985–8000, https://doi.org/10.5194/acp-18-7985-2018, https://doi.org/10.5194/acp-18-7985-2018, 2018
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The long-term (2002–2016) variability of global and diffuse PAR over the central Mediterranean is investigated based on measurements from Lampedusa. PAR modulates biological processes and this study provides useful insight into its variability. Seasonal and interannual variability of global and diffuse PAR is characterized and the effects of clouds are quantified. The analysis suggests that 77 % of the global PAR interannual variability may be ascribed to clouds.
Stelios Kazadzis, Dimitra Founda, Basil E. Psiloglou, Harry Kambezidis, Nickolaos Mihalopoulos, Arturo Sanchez-Lorenzo, Charikleia Meleti, Panagiotis I. Raptis, Fragiskos Pierros, and Pierre Nabat
Atmos. Chem. Phys., 18, 2395–2411, https://doi.org/10.5194/acp-18-2395-2018, https://doi.org/10.5194/acp-18-2395-2018, 2018
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The National Observatory of Athens has been collecting solar radiation, sunshine duration, and cloud and visibility data/observations since the beginning of the 20th century. In this work we present surface solar radiation data since 1953 and reconstructed data since 1900. We have attempted to show and discuss the long-term changes in solar surface radiation over Athens, Greece, using these unique datasets.
Klára Čížková, Kamil Láska, Ladislav Metelka, and Martin Staněk
Atmos. Chem. Phys., 18, 1805–1818, https://doi.org/10.5194/acp-18-1805-2018, https://doi.org/10.5194/acp-18-1805-2018, 2018
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In order to broaden the knowledge of long-term UV radiation variability, we have reconstructed and analyzed a 50-year-long UV radiation time series from Hradec Králové, Czech Republic. The UV radiation intensities increased greatly following the decline of ozone amounts in the 1980s and 1990s. High UV radiation doses were observed in days with low ozone amounts, clear or partly cloudy skies, or snow cover.
Janusz W. Krzyścin and Piotr S. Sobolewski
Atmos. Chem. Phys., 18, 1–11, https://doi.org/10.5194/acp-18-1-2018, https://doi.org/10.5194/acp-18-1-2018, 2018
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Maintaining homogeneity of long-term UV time series taken from various instruments and thus trend estimation are challenging tasks, especially for remote Arctic sites.
Highlights: method of the UV data homogenization is proposed to be used at any remote site. Past UV data built from satellite total O3 and ground-based sunshine duration. Yearly UV doses trendless in the southern Svalbard for 34-year period since 1983. Long-term cloud effects on UV more important than the ozone effects there.
Werner Eugster, Carmen Emmel, Sebastian Wolf, Nina Buchmann, Joseph P. McFadden, and Charles David Whiteman
Atmos. Chem. Phys., 17, 14887–14904, https://doi.org/10.5194/acp-17-14887-2017, https://doi.org/10.5194/acp-17-14887-2017, 2017
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The effects of penumbral shading of the solar eclipse of 20 March 2015 on near-surface meteorology across Switzerland (occultation 65.8–70.1 %) was investigated. Temperature effects at 184 weather stations are compared with temperature drops reported in the literature since 1834. A special focus is, however, put on wind direction effects observed at six flux sites (with 20 Hz data) and 165 meteorological stations (with 10 min resolution data). Results show the importance of local topography.
Reinout Boers, Theo Brandsma, and A. Pier Siebesma
Atmos. Chem. Phys., 17, 8081–8100, https://doi.org/10.5194/acp-17-8081-2017, https://doi.org/10.5194/acp-17-8081-2017, 2017
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In the Netherlands 9 W m−2 more solar radiation falls on the surface today than 50 years ago. Often this increase, which has also been detected in surrounding western Europe, has been attributed to decreasing air pollution due to improved regulatory practices. However, over the Netherlands clouds play an important but ambiguous role. Cloud cover has increased but have become optically thinner as well. Here, the impact of clouds on radiation is in fact more important than that of air pollution.
Jizeng Du, Kaicun Wang, Jiankai Wang, and Qian Ma
Atmos. Chem. Phys., 17, 4931–4944, https://doi.org/10.5194/acp-17-4931-2017, https://doi.org/10.5194/acp-17-4931-2017, 2017
Bomidi Lakshmi Madhavan, Hartwig Deneke, Jonas Witthuhn, and Andreas Macke
Atmos. Chem. Phys., 17, 3317–3338, https://doi.org/10.5194/acp-17-3317-2017, https://doi.org/10.5194/acp-17-3317-2017, 2017
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A method has been introduced to assess the representativeness of the time series of a point measurement compared to results for a larger area centered around the measurement location. This method allows one to determine the optimal accuracy that can be achieved for the validation of satellite products for a given pixel footprint, or the evaluation of an atmospheric model with a given grid-cell resolution.
Colette Brogniez, Frédérique Auriol, Christine Deroo, Antti Arola, Jukka Kujanpää, Béatrice Sauvage, Niilo Kalakoski, Mikko Riku Aleksi Pitkänen, Maxime Catalfamo, Jean-Marc Metzger, Guy Tournois, and Pierre Da Conceicao
Atmos. Chem. Phys., 16, 15049–15074, https://doi.org/10.5194/acp-16-15049-2016, https://doi.org/10.5194/acp-16-15049-2016, 2016
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The atmospheric ozone layer is changing, thus the UV radiation at the surface is changing. Due to both beneficial and adverse effects of UV on the biosphere, monitoring of UV is essential. Satellite sensors provide estimates of UV at the surface with a global coverage. Validation of satellite-sensor UV is therefore needed and this can be done by comparison with ground-based measurements. The present validation in three sites (midlatitude, tropical) shows that OMI and GOME-2 provide reliable UV.
Katsumasa Tanaka, Atsumu Ohmura, Doris Folini, Martin Wild, and Nozomu Ohkawara
Atmos. Chem. Phys., 16, 13969–14001, https://doi.org/10.5194/acp-16-13969-2016, https://doi.org/10.5194/acp-16-13969-2016, 2016
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Surface solar radiation observed in Japan generally shows a strong decline until the end of the 1980s and then a recovery up until around 2000. A substantial number of measurement stations are located close to populated areas and are speculated to have been influenced by air pollution. However, data obtained at 14 meteorological observatories suggest that the large decadal variations in surface solar radiation occur on a large scale and not limited to urban areas.
Jianping Guo, Yucong Miao, Yong Zhang, Huan Liu, Zhanqing Li, Wanchun Zhang, Jing He, Mengyun Lou, Yan Yan, Lingen Bian, and Panmao Zhai
Atmos. Chem. Phys., 16, 13309–13319, https://doi.org/10.5194/acp-16-13309-2016, https://doi.org/10.5194/acp-16-13309-2016, 2016
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The large-scale PBL climatology from sounding observations is still lacking in China. This work investigated the BLH characterization at diurnal, monthly and seasonal timescales throughout China, showing large geographic and meteorological dependences. BLH is, on average, negatively (positively) associated with the surface pressure and lower tropospheric stability (wind speed and temperature). Cloud tends to suppress the development of the PBL, which has implications for air quality forecasts.
Veronica Manara, Michele Brunetti, Angela Celozzi, Maurizio Maugeri, Arturo Sanchez-Lorenzo, and Martin Wild
Atmos. Chem. Phys., 16, 11145–11161, https://doi.org/10.5194/acp-16-11145-2016, https://doi.org/10.5194/acp-16-11145-2016, 2016
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This paper presents the temporal evolution of solar radiation over Italy for the 1959–2013 period and discusses possible reasons for differences between all-sky and clear-sky conditions in order to understand which part of the solar radiation variability depends on aerosols or clouds. The results give evidence of a relevant influence of both anthropogenic and natural aerosols on solar radiation long-term variability.
Weidong Guo, Xueqian Wang, Jianning Sun, Aijun Ding, and Jun Zou
Atmos. Chem. Phys., 16, 9875–9890, https://doi.org/10.5194/acp-16-9875-2016, https://doi.org/10.5194/acp-16-9875-2016, 2016
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Basic characteristics of land–atmosphere interactions at four neighboring sites with different underlying surfaces in southern China, a typical monsoon region, are analyzed systematically. Despite the same climate background, the differences in land surface characteristics like albedo and aerodynamic roughness length due to land use/cover change exert distinct influences on the surface radiative budget and energy allocation and result in differences of near-surface micrometeorological elements.
Fanny Finger, Frank Werner, Marcus Klingebiel, André Ehrlich, Evelyn Jäkel, Matthias Voigt, Stephan Borrmann, Peter Spichtinger, and Manfred Wendisch
Atmos. Chem. Phys., 16, 7681–7693, https://doi.org/10.5194/acp-16-7681-2016, https://doi.org/10.5194/acp-16-7681-2016, 2016
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Solar spectra of optical layer properties of cirrus have been derived from the first truly collocated airborne radiation measurements using an aircraft and a towed sensor platform. The measured layer properties differ slightly due to horizontal cirrus inhomogeneities and the influence of low-level water clouds. Applying a 1-D radiative transfer model sensitivity studies were performed. It was found that if a low-level cloud is not considered, the solar cooling of the cirrus is strongly overestimated.
Gerald M. Lohmann, Adam H. Monahan, and Detlev Heinemann
Atmos. Chem. Phys., 16, 6365–6379, https://doi.org/10.5194/acp-16-6365-2016, https://doi.org/10.5194/acp-16-6365-2016, 2016
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Increasing numbers of photovoltaic (PV) power systems call for the characterization of irradiance variability with very high spatiotemporal resolution. We use 1 Hz irradiance data recorded by as many as 99 pyranometers and show mixed sky conditions to differ substantially from clear and overcast skies. For example, the probabilities of strong fluctuations and their respective spatial autocorrelation structures are appreciably distinct under mixed conditions.
John H. Marsham, Douglas J. Parker, Martin C. Todd, Jamie R. Banks, Helen E. Brindley, Luis Garcia-Carreras, Alexander J. Roberts, and Claire L. Ryder
Atmos. Chem. Phys., 16, 3563–3575, https://doi.org/10.5194/acp-16-3563-2016, https://doi.org/10.5194/acp-16-3563-2016, 2016
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The roles of water, clouds and airborne dust in controlling the heating of the Sahara are uncertain, which has major implications for the West African monsoon. Observations from the Fennec project, with satellite data, show that total atmospheric water content provides a far stronger control on total radiative heating than dust does, but dust provides the stronger control on surface heating. Therefore major heating errors in global models are likely due to known errors in water transport.
Adel Imamovic, Katsumasa Tanaka, Doris Folini, and Martin Wild
Atmos. Chem. Phys., 16, 2719–2725, https://doi.org/10.5194/acp-16-2719-2016, https://doi.org/10.5194/acp-16-2719-2016, 2016
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Systematic measurements of surface solar radiation revealed a worldwide decrease from the 1960s to the mid-1980s. The role of urbanization for this so called global dimming is still under debate. We developed a set of population-data based urbanization indicators and found no correlation between urbanization and global dimming for Europe and Japan, while an urbanization impact can't be precluded for Asia. It is thus called into question whether the global dimming was mainly a local phenomenon.
Ilias Fountoulakis, Alkiviadis F. Bais, Konstantinos Fragkos, Charickleia Meleti, Kleareti Tourpali, and Melina Maria Zempila
Atmos. Chem. Phys., 16, 2493–2505, https://doi.org/10.5194/acp-16-2493-2016, https://doi.org/10.5194/acp-16-2493-2016, 2016
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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.
Costas A. Varotsos, Chris G. Tzanis, and Nicholas V. Sarlis
Atmos. Chem. Phys., 16, 2007–2011, https://doi.org/10.5194/acp-16-2007-2016, https://doi.org/10.5194/acp-16-2007-2016, 2016
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It has been recently reported that the current 2015–2016 El Niño could become "one of the strongest on record". To further explore this claim, we performed a new analysis that allows the detection of precursory signals of the strong El Niño events by using a recently developed non-linear dynamics tool. The analysis of the SOI time series shows that the 2015–2016 El Niño would be rather a "moderate to strong" or even a "strong” event and not "one of the strongest on record", as that of 1997–1998.
X. Guan, J. Huang, R. Guo, H. Yu, P. Lin, and Y. Zhang
Atmos. Chem. Phys., 15, 13777–13786, https://doi.org/10.5194/acp-15-13777-2015, https://doi.org/10.5194/acp-15-13777-2015, 2015
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Dynamical adjustment methodology has been applied to the raw surface air temperature and has successfully identified and separated the contribution of dynamically induced temperature (DIT) and radiatively forced temperature (RFT). It found that regional anthropogenic radiative forcing caused the enhanced warming in the semi-arid region, which may be closely associated with local human activities.
C.-M. Gan, J. Pleim, R. Mathur, C. Hogrefe, C. N. Long, J. Xing, D. Wong, R. Gilliam, and C. Wei
Atmos. Chem. Phys., 15, 12193–12209, https://doi.org/10.5194/acp-15-12193-2015, https://doi.org/10.5194/acp-15-12193-2015, 2015
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This study attempts to determine the consequences of the changes in tropospheric aerosol burden arising from substantial reductions in emissions of SO2 and NOx associated with control measures under the Clean Air Act especially on trends in solar radiation. Comparisons of model results with observations of aerosol optical depth, aerosol concentration, and radiation demonstrate that the coupled WRF-CMAQ model is capable of replicating the trends well even though it tends to underestimate the AOD.
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, https://doi.org/10.5194/acp-15-7391-2015, https://doi.org/10.5194/acp-15-7391-2015, 2015
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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.
S. R. Wilson
Atmos. Chem. Phys., 15, 7337–7349, https://doi.org/10.5194/acp-15-7337-2015, https://doi.org/10.5194/acp-15-7337-2015, 2015
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Measurements of the photolysis rates which drive production of OH from ozone are reported for Cape Grim, a "clean-air" site in the southern midlatitudes. This remote maritime site sits in the Southern Ocean, a region of the globe which is little studied. From the 6 years of data the dependence of this photolysis on solar zenith angle and stratospheric ozone is determined. Included with the reported values is an estimate of the uncertainties in these measurements.
C. A. Varotsos, S. Lovejoy, N. V. Sarlis, C. G. Tzanis, and M. N. Efstathiou
Atmos. Chem. Phys., 15, 7301–7306, https://doi.org/10.5194/acp-15-7301-2015, https://doi.org/10.5194/acp-15-7301-2015, 2015
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Varotsos et al. (Theor. Appl. Climatol., 114, 725–727, 2013) found that the solar ultraviolet (UV) wavelengths exhibit 1/f-type power-law correlations. In this study, we show that the residues of the spectral solar incident flux with respect to the Planck law over a wider range of wavelengths (i.e. UV-visible) have a scaling regime too.
P. Wang, M. Allaart, W. H. Knap, and P. Stammes
Atmos. Chem. Phys., 15, 4131–4144, https://doi.org/10.5194/acp-15-4131-2015, https://doi.org/10.5194/acp-15-4131-2015, 2015
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A green light sensor has been developed at KNMI to measure actinic flux profiles together with an ozonesonde. The impact of clouds on the actinic flux is clearly detected. Good agreement is found between the DAK-simulated actinic flux profiles and the observations for single-layer clouds in fully overcast scenes. The instrument is suitable for operational balloon measurements because of its simplicity and low cost.
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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.
We have done measurements of the sky's brightness at the Italian coast and show the influence of...
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