On the crucial role of atmospheric rivers in the two major Weddell Polynya events in 1973 and 2017 in Antarctica
This study reports the occurrence of intense atmospheric rivers (ARs) during the two large Weddell Polynya events in November 1973 and September 2017 and investigates their role in the opening events via their enhancement of sea ice melt. Few days before the polynya openings, persistent ARs maintained a sustained positive total energy flux at the surface, resulting in sea ice thinning and a decline in sea ice concentration in the Maud Rise region. The ARs were associated with anomalously high amounts of total precipitable water and cloud liquid water content exceeding 3 SDs above the climatological mean. The above-normal integrated water vapor transport (IVT above the 99th climatological percentile), as well as opaque cloud bands, warmed the surface (+10°C in skin and air temperature) via substantial increases (+250 W m−2) in downward longwave radiation and advection of warm air masses, resulting in sea ice melt and inhibited nighttime refreezing.
Publication titleScience Advances
Department/SchoolInstitute for Marine and Antarctic Studies
PublisherAmerican Association for the Advancement of Science (AAAS)
Place of publicationUnited States
Rights statementCopyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial 4.0 International (CC BY-NC 4.0) License (https://creativecommons.org/licenses/by-nc/4.0/)