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Abstract :
[en] Atmospheric rivers (AR) of high intensity occur rarely in the Polar regions but can play an important role in the regional climate-state extremes. In Antarctica, intense ARs have caused remarkable impacts during recent years, including record-high surface melt over the Antarctic Peninsula (AP) in February 2022 (Gorodetskaya et al., 2023) and the strongest heatwave ever recorded over East Antarctica bringing extreme inland snowfall and coastal surface melt in March 2022 (Wille et al., 2024). The AP event particularly demonstrated that an intense AR can induce a strong impact on the surface energy and mass balance in a short time (less than two days). Here we extend this analysis considering all AR events greater than category 3 (following classification described by Zhang et al, 2024) reaching the AP coast with a focus on 2022-2024. We analyse the time evolution of precipitation and surface melt using observations at the King Sejong station (northern AP) and Vernadsky station (northwestern AP) including thermodynamic structure of the troposphere measured with radiosondes and precipitation profiles from MRR-PRO radar. Further, we use highresolution model simulations (regional climate model MAR and Polar-WRF) forced by ERA5 reanalysis, along with surface melt derived from microwave satellite observations, to show the spatial scale of specific events over the entire AP, regarding both snowfall to rainfall transition and surface melt.
