Contrasting anthropogenic drivers behind asymmetric warming in the Arctic and Antarctica

Kurzfassung

Surface air temperature (SAT) in polar regions is rising faster than the global average. This study analyzes the rapid increase in anthropogenic influences throughout the industrial period on Arctic and Antarctic warming, utilizing climate models. Our results show that while the SAT trend in the Arctic due to greenhouse gas (GHG) forcing is approximately 0.6C/Decade, twice that of land use (LU) forcing at 0.3C/Decade, the amplification of Arctic warming from LU forcings (with an amplification factor of 2.37) is stronger than the GHG forcings (amplification factor of 2.25). Whereas, anthropogenic aerosols cool the Arctic 1.5 times more than Antarctica, driven by higher aerosol concentrations from long-range pollutant transport from lower latitudes. Since 1950, rapid industrialization in the Northern Hemisphere has caused Arctic warming to accelerate, with SAT rising by 0.34C/Decade due to anthropogenic forcings - over twice the global average of 0.17C/Decade. In contrast, Antarctic warming has remained closer to global trends, buffered by its remoteness from the anthropogenic influence. Under the high-emission scenario (RCP 8.5), both polar regions are projected to experience substantial temperature increases by the end of the 21st century, underscoring the significant role of human activities in polar warming and the need for targeted interventions addressing regional and global changes in LU, GHG emissions, and anthropogenic aerosols.