Factors Driving Past Trends in Arctic Precipitation and Their Future Changes

Abstract

The Arctic is notable as a region where the greatest rate of increase in precipitation associated with global warming is anticipated. The Arctic precipitation simulated by the Coupled Model Intercomparison Project phase 6 multimodels showed a strong increasing trend in the recent past since the 1980s as a result of the continued strengthening of greenhouse gas forcing. Meanwhile, the suppression by aerosol forcing, which dominated in earlier periods, has been leveled off. From an energetic perspective, the constraining factors of increased atmospheric radiative cooling and reduced heat transport from lower latitudes contributed equally to the recent increase in Arctic precipitation. Future Arctic precipitation will change in proportion to the temperature change, but the fractional contributions of the constraining factors will remain stable across various scenarios. The implications for the doubling of the Arctic amplification factor of precipitation changes relative to that of temperature changes are also discussed.