Spatial Distribution of Aerosol Characteristics over the South Atlantic and Southern Ocean Using Multiyear (2004–2021) Measurements from Russian Antarctic Expeditions

Atmosphere

Olga R. Sidorova¹  Vladimir F. Radionov¹  Liudmila P. Golobokova²  Sergey M. Sakerin³  Viktor V. Pol’kin³  Dmitry M. Kabanov³  Olga I. Khuriganowa³  Yuri S. Turchinovich³ 

[1] Arctic and Antarctic Reserch Institute, 38 Bering Str., 199397 St. Petersburg, Russia;Limnology Institute, Siberian Branch, Russian Academy of Sciences, Ulan-Batorskaya 3, 664033 Irkutsk, Russia;V.E. Zuev Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, Academician Zuev Square 1, 634021 Tomsk, Russia;

关键词: aerosol;    black carbon;    ionic composition;    spatial distribution;    Southern Ocean;    South Atlantic;   

DOI  :  10.3390/atmos13030427

来源: DOAJ

【 摘 要 】

Since 2004, we have carried out yearly measurements of physicochemical aerosol characteristics onboard research vessels at Southern Hemisphere high latitudes (34–72° S; 45° W–110° E). In this work, we statistically generalize the results from multiyear (2004–2021) measurements in this area of the aerosol optical depth (AOD) of the atmosphere, concentrations of aerosol and equivalent black carbon (EBC), as well as the ionic composition of aerosol. A common regularity was that the aerosol characteristics decreased with increasing latitude up to the Antarctic coast, where the aerosol content corresponded to the global background level. Between Africa and Antarctica, AOD decreased from 0.07 to 0.024, the particle volume decreased from 5.5 to 0.55 µm³/cm³, EBC decreased from 68.1 to 17.4 ng/m³, and the summed ion concentration decreased from 24.5 to 2.5 µg/m³. Against the background of the common tendency of the latitude decrease in aerosol characteristics, we discerned a secondary maximum (AOD and ion concentrations) or a plateau (aerosol and EBC concentrations). The obtained spatial distribution of aerosol characteristics qualitatively agreed with the model-based MERRA-2 reanalysis data, but showed quantitative differences: the model AOD values were overestimated (by 0.015, on average); while the EBC concentrations were underestimated (by 21.7 ng/m³). An interesting feature was found in the aerosol spatial distribution in the region of Antarctic islands: at a distance of 300 km from the islands, the concentrations of EBC decreased on average by 29%, while the aerosol content increased by a factor of 2.5.

【 授权许可】

Unknown