Seasonal changes in black carbon footprint on the Antarctic Peninsula due to rising shipborne tourism and forest fires.

Refractory black carbon (rBC) has great potential to increase melting when deposited on snow and ice surfaces. Previous studies attributed sources and impacts of rBC in the northern Antarctic Peninsula region by investigating long-range atmospheric transport from South Hemisphere biomass burning and industrial regions or by assessing impacts from local tourism and research activities. We used high-resolution measurements of refractory rBC in a firn core collected near the northern tip of the Antarctic Peninsula, as well as atmospheric rBC from Modern-Era Retrospective Analysis for Research and Applications, Version 2, satellite measurements, modeling, burned area data, and tourism statistics, to assess combined impacts of both long-range transported rBC and locally emitted rBC. Our findings suggest that tourism activities have a regional rather than local impact and the increase in rBC concentrations during late spring-summer, influenced by tourism activities and fires in the Southern Hemisphere, can enhance ice melt. This highlights the need for strategies to reduce local and distant rBC emissions.