BC can be transported through the atmosphere from low and mid-latitudes to Antarctica, or it can be emitted in the Antarctica in situ. To establish a possible relationship between BC and the human activities in Antarctica, shallow snow samples were taken in four sites from Antarctic peninsula during summer periods (2014-2019): Chilean Base O'Higgins (BO), La Paloma Glacier (LP) (6 km away from BO); Chilean Base Yelcho (BY) and P4 (5 km away from BY). BC concentration in snow samples was determined by using a novel methodology recently developed, published and patented by the authors. The methodology consisted in a filter-based optical transmission method at a wavelength of 880 nm. Results showed that snow from BO presented the highest BC concentration (3395.7 μg kg-1), followed by BY (1309.2 μg kg-1), LP 2016 (745.9 μg kg-1), LP 2015 (233.6 μg kg-1) and finally P4 (179.4 μg kg-1). BC values observed in Antarctic snow were higher than others previously reported in the literature and showed the influence of anthropic activities in the study area, considering that the two highest values of BC concentration in snow were found at sites near the bases. To evaluate the impact of the BC concentrations found in the snow of the study area, snow albedo modeling was performed, using the on-line version of the "Snow, Ice, and Aerosol Radiative" (SNICAR) Model. Modeling outputs exposed that the measured variations in BC content caused large differences in the modeled albedo in the visible range of the spectra, which showed to be more sensitive at lower BC concentrations. These data could help to understand the role of BC in the actual scenario of climate change, in which Antarctica is presented as a very fragile environment that needs to be protected, starting with the management of the activities developed in-situ.
Keywords: BC in snow; Chilean Stations in Antarctica; Snow albedo.
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