Modeling Circumpolar Deep Water intrusion onto the Bellingshausen Sea continental shelf

Shuntaro Hyogo, Graduate School of Environmental Sciences, Hokkaido University, Sapporo, Japan and Yoshihiro Nakayama, Institute of Low Temperature Science, Hokkaido University, Sapporo, Japan
Abstract:
The ice shelves and glaciers of the West Antarctic Ice Sheet are thinning rapidly in the Amundsen and Bellingshausen Seas. The high basal melt rate of these ice shelves is caused by warm Circumpolar Deep Water (CDW) that mainly intrudes via submarine glacial troughs located at the continental shelf break. Here, we conduct ocean simulation for a regional Amundsen and Bellingshausen Sea configuration of the Massachusetts Institute of Technology general circulation model (MITgcm). Model simulation is conducted between 2001-2016. The regional MITgcm configuration includes dynamic/thermodynamic sea ice and static thermodynamic ice shelf representation. Horizontal spacing is about 3 km and there are 70 vertical levels ranging thickness from 10 m near the surface to ~450 m near the bottom. Although previous studies focused on the ocean circulation in the Amundsen Sea, no analysis has been conducted for the Bellingshausen Sea using this ocean simulation. In this poster presentation, we evaluate our model by comparing with exiting observations (ship-based and seal CTDs). We further investigate pathways of CDW intrusion as well as spreading of glacial meltwater.