Examining Atmospheric River Life Cycles in East Antarctica ...

• Main Authors: Wille, Jonathan D., Pohl, Benjamin, Favier, Vincent, Winters, Andrew C., Baiman, Rebecca, Cavallo, Steven M., Leroy-Dos Santos, Christophe, Clem, Kyle, Udy, Danielle G., Vance, Tessa R., Gorodetskaya, Irina, Codron, Francis, Berchet, Antoine
• Format: Text
• Language: English
• Published: ETH Zurich 2024
• Subjects: atmospheric rivers; Antarctica; atmospheric dynamics; atmospheric blocking; diabatic processes; Antarc*; Antarctic; East Antarctica; Ice Sheet
• Online Access: https://dx.doi.org/10.3929/ethz-b-000670426; http://hdl.handle.net/20.500.11850/670426

During atmospheric river (AR) landfalls on the Antarctic ice sheet, the high waviness of the circumpolar polar jet stream allows for subtropical air masses to be advected toward the Antarctic coastline. These rare but high-impact AR events are highly consequential for the Antarctic mass balance; yet little is known about the various atmospheric dynamical components determining their life cycle. By using an AR detection algorithm to retrieve AR landfalls at Dumont d'Urville and non-AR analogs based on 700 hPa geopotential height, we examined what makes AR landfalls unique and studied the complete life cycle of ARs reaching Dumont d'Urville. ARs form in the mid-latitudes/subtropics in areas of high surface evaporation, likely in response to tropical deep convection anomalies. These convection anomalies likely lead to Rossby wave trains that help amplify the upper-tropospheric flow pattern. As the AR approaches Antarctica, condensation of isentropically lifted moisture causes latent heat release that-in ... : Journal of Geophysical Research: Atmospheres, 129 (8) ...