Increasing wintertime cloud opacity increases surface longwave radiation at a long-term Arctic observatory.

ABSTRACT: As the Arctic warms, winter clouds are known and expected to change. Yet the extent to which these cloud changes amplify or dampen warming (cloud feedback) remains uncertain. This uncertainty results from systemic difficulties in modeling and observing Arctic low clouds. Surface-based observations avoid many of these difficulties. Here, we use two decades of surface-based observations (1998-2023) to constrain and explain longwave flux change during winter. We find that longwave flux into the surface is increasing and that this increase cannot be explained by direct impacts of temperature and greenhouse gases alone. Only when increasing cloud radiative effect (0.96 ± 0.64 W/m²/K) is considered can increasing longwave flux be explained. Cloud radiative effect increases due to incr

SUBMITTER: Bertrand L 

PROVIDER: S-EPMC12579616 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature