A 20-year study of melt processes over Larsen C Ice Shelf using a high-resolution regional atmospheric model: Part 2, Drivers of surface melting

Abstract

Atmospheric drivers of surface melting were implicated in the collapse of the Larsen A and B ice shelves that previously neighbored Larsen C-the largest remaining ice shelf on the eastern side of the Antarctic Peninsula and which extends north of the Antarctic circle-by increasing firn densification, meltwater ponding, and ultimately hydrofracturing and disintegration (Bell et al., 2018;Scambos et al., 2000). In particular, the large-scale circumpolar westerly circulation is known to have an important role in the Antarctic Peninsula region by influencing local atmospheric conditions via its effect on foehn winds. Foehn winds cause leeside warming and associated melting over these ice shelves (

The importance of cloud phase when assessing surface melting in an offline coupled firn model over Ross Ice shelf, West Antarctica

“…The relatively high temperatures that are associated with Antarctic ice shelf melting are usually in response to local and mesoscale circulations such as barrier winds, katabatic winds, and foehn winds (Orr et al, 2004(Orr et al, , 2023Coggins et al, 2014;Lenaerts et al, 2017a;Heinemann et al, 2019;Zou et al, 2021Zou et al, , 2023Carter et al, 2022;Gilbert et al, 2022), as well as synoptic scale circulation patterns that facilitate the incursion of warm maritime airmasses, such as atmospheric rivers (Nicolas and Bromwich, 2011;Nicolas et al, 2017;Bozkurt et al, 2018;Scott et al, 2019;Wille et al, 2019Wille et al, , 2022Turner et al, 2022;Orr et al, 2023;Zou et al, 2023). Therefore, to realistically capture local climate variability and simulate ice shelf melt patterns, it is essential to utilize regional atmospheric models at high spatial resolution, i.e., grid box sizes of the order 10 km or less.…”