Aerosol remote sensing in polar regions

• Published in: Earth-Science Reviews
• Main Authors: Tomasi, Claudio, Kokhanovsky, Alexander A., Lupi, Angelo, Ritter, Christoph, Smirnov, Alexander, O'Neill, Norman T., Stone, Robert S., Holben, Brent N., Nyeki, Stephan, Wehrli, Christoph, Stohl, Andreas, Mazzola, Mauro, Lanconelli, Christian, Vitale, Vito, Stebel, Kerstin, Aaltonen, Veijo, de Leeuw, Gerrit, Rodriguez, Edith, Herber, Andreas B., Radionov, Vladimir F., Zielinski, Tymon, Petelski, Tomasz, Sakerin, Sergey M., Kabanov, Dmitry M., Xue, Yong, Mei, Linlu, Istomina, Larysa, Wagener, Richard, McArthur, Bruce, Sobolewski, Piotr S., Kivi, Rigel, Courcoux, Yann, Larouche, Pierre, Broccardo, Stephen, Piketh, Stuart J.
• Language: unknown
• Published: 2023
• Subjects: 54 ENVIRONMENTAL SCIENCES; Antarctic; Antarctic Peninsula; Arctic; Arctic Ocean; Austral; Indian; Ny-Ålesund; Pacific; The Antarctic; Antarc*; Antarctica; Ny Ålesund
• Online Access: http://www.osti.gov/servlets/purl/1167151; https://www.osti.gov/biblio/1167151; https://doi.org/10.1016/j.earscirev.2014.11.001

Multi-year sets of ground-based sun-photometer measurements conducted at 12 Arctic sites and 9 Antarctic sites were examined to determine daily mean values of aerosol optical thickness τ(λ) at visible and near-infrared wavelengths, from which best-fit values of Ångström's exponent α were calculated. Analysing these data, the monthly mean values of τ(0.50 μm) and α and the relative frequency histograms of the daily mean values of both parameters were determined for winter–spring and summer–autumn in the Arctic and for austral summer in Antarctica. The Arctic and Antarctic covariance plots of the seasonal median values of α versus τ(0.50 μm) showed: (i) a considerable increase in τ(0.50 μm) for the Arctic aerosol from summer to winter–spring, without marked changes in α; and (ii) a marked increase in τ(0.50 μm) passing from the Antarctic Plateau to coastal sites, whereas α decreased considerably due to the larger fraction of sea-salt aerosol. Good agreement was found when comparing ground-based sun-photometer measurements of τ(λ) and α at Arctic and Antarctic coastal sites with Microtops measurements conducted during numerous AERONET/MAN cruises from 2006 to 2013 in three Arctic Ocean sectors and in coastal and off-shore regions of the Southern Atlantic, Pacific, and Indian Oceans, and the Antarctic Peninsula. Lidar measurements were also examined to characterise vertical profiles of the aerosol backscattering coefficient measured throughout the year at Ny-Ålesund. Satellite-based MODIS, MISR, and AATSR retrievals of τ(λ) over large parts of the oceanic polar regions during spring and summer were in close agreement with ship-borne and coastal ground-based sun-photometer measurements. An overview of the chemical composition of mode particles is also presented, based on in-situ measurements at Arctic and Antarctic sites. Fourteen log-normal aerosol number size-distributions were defined to represent the average features of nuclei, accumulation and coarse mode particles for Arctic haze, summer background aerosol, ...