Print Email Facebook Twitter Atmospheric Triggers of the Brunt Ice Shelf Calving in February 2021 Title Atmospheric Triggers of the Brunt Ice Shelf Calving in February 2021 Author Francis, Diana (Khalifa University) Fonseca, Ricardo (Khalifa University) Mattingly, Kyle S. (University of Wisconsin-Madison) Marsh, Oliver J. (British Antarctic Survey) Lhermitte, S.L.M. (TU Delft Mathematical Geodesy and Positioning) Cherif, Charfeddine (Khalifa University) Date 2022 Abstract The calving of Antarctic ice shelves remains unpredictable to date due to a lack of understanding of the role of the different climatic components in such events. In this study, the role of atmospheric forcing in the calving of the Brunt Ice Shelf (BIS) in February 2021 is investigated using a combination of observational and reanalysis data. The occurrence of a series of extreme cyclones around the time of the calving induced an oceanward sea-surface slope of >0.08° leading to the calving along a pre-existing rift. The severe storms were sustained by the development of a pressure dipole on both sides of the BIS associated with a La Niña event and the positive phase of the Southern Annular Mode. Poleward advection of warm and moist low-latitude air over the BIS area just before the calving was also observed in association with atmospheric rivers accompanying the cyclones. Immediately after the calving, strong offshore winds continued and promoted the drift of the iceberg A-74 in the Weddell Sea at a speed up to 700 m day−1. This study highlights the contribution of local atmospheric conditions to ice-shelf dynamics. The link to the larger scale circulation patterns indicates that both need to be accounted for in the projections of Antarctic ice shelf evolution. Subject atmospheric riverscircumglobal wave trainice shelf calvingocean slopepolar cycloneszonal wavenumber 3 (ZW3) To reference this document use: http://resolver.tudelft.nl/uuid:baee657b-c19d-44da-8da5-4ba19be765c1 DOI https://doi.org/10.1029/2021JD036424 Embargo date 2022-11-18 ISSN 2169-897X Source Journal Of Geophysical Research-Atmospheres, 127 (11) Part of collection Institutional Repository Document type journal article Rights © 2022 Diana Francis, Ricardo Fonseca, Kyle S. Mattingly, Oliver J. Marsh, S.L.M. Lhermitte, Charfeddine Cherif Files PDF JGR_Atmospheres_2022_Fran ... y_2021.pdf 4.31 MB Close viewer /islandora/object/uuid:baee657b-c19d-44da-8da5-4ba19be765c1/datastream/OBJ/view