Multidecadal trend analysis of aerosol radiative properties at a global scale

• Published in: Atmospheric Chemistry and Physics
• Main Authors: Collaud Coen, Martine, Andrews, Elisabeth, Alastuey, Andrès, Arsov, Todor Petkov, Backman, John, Brem, Benjamin Tobias, Bukowiecki, Nicolas Bukowiecki, Couret, Cédric Couret, Eleftheriadis, Konstantinos, Flentje, Harald, Fiebig, Markus, Gysel-Beer, Martin, Hand, Jenny L., Hoffer, Andràs, Hooda, Rakesh, Hueglin, Christoph, Joubert, Warren, Keywood, Melita, Kim, Jeong Eun, Kim, Sang-Woo, Labuschagne, Labuschagne, Lin, Neng-Huei, Lin, Yong, Lund Myhre, Cathrine, Luoma, Krista, Lyamani, Hassan, Marinoni, Angela, Mayol-Bracero, Olga L., Mihalopoulos, Nikos, Pandolfi, Marco, Prats, Natalia, Prenni, Anthony J., Putaud, Jean-Philippe, Ries, Ludwig, Riesen, Fabienne, Sellegri, Karine, Sharma, Sangeeta, Sheridan, Patrick, Sherman, James Patrick, Sun, Junying, Titos, Gloria, Torres, Elvis, Tuch, Thomas, Weller, Rolf, Wiedensohler, Alfred, Zieger, Paul, Laj, Paolo
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: COPERNICUS GESELLSCHAFT MBH 2020
• Subjects: albedo; Climate change
• Online Access: https://epic.awi.de/id/eprint/50792/; https://epic.awi.de/id/eprint/50792/1/Collaud_Trenpaper_acp-20-8867-2020.pdf; https://www.atmos-chem-phys.net/20/8867/2020/; https://hdl.handle.net/10013/epic.8a4c9b48-0964-4545-b26a-1de501784a43

In order to assess the global evolution of aerosol parameters affecting climate change, a long-term trend analyses of aerosol optical properties were performed on time series from 52 stations situated across five continents. The time series of measured scattering, backscattering and absorption coefficients as well as the derived single scattering albedo, backscattering fraction, scattering and absorption Ångström exponents covered at least 10 years and up to 40 years for some stations. The non-parametric seasonal Mann-Kendall (MK) statistical test associated with several prewhitening methods and with the Sen’s slope were used as main trend analysis methods. Comparisons with General Least Mean Square associated with Autoregressive Bootstrap (GLS/ARB) and with standard Least Mean Square analysis (LMS) enabled confirmation of the detected MK statistically significant trends and the assessment of advantages and limitations of each method. Currently, scattering and backscattering coefficients trends are mostly decreasing in Europe and North America and are not statistically significant in Asia, while polar stations exhibit a mix of increasing and decreasing trends. A few increasing trends are also found at some stations in North America and Australia. Absorption coefficients time series also exhibit primarily decreasing trends. For single scattering albedo, 52% of the sites exhibit statistically significant positive trends, mostly in Asia, Eastern/Northern Europe and Arctic, 18% of sites exhibit statistically significant negative trends, mostly in central Europe and central North America, while the remaining 30% of sites have trends, which are not statistically significant. In addition to evaluating trends for the overall time series, the evolution of the trends in sequential 10 year segments was also analyzed. For scattering and backscattering, statistically significant increasing 10 year trends are primarily found for earlier periods (10 year trends ending in 2010-2015) for polar stations and Mauna Loa. For most of ...