Southern Annular Mode, Foehn Wind, and Larsen C Ice Shelf
Dr. Jing Zhang
The Antarctica Peninsula (AP) has undergone a rapid increase of temperature within the recent decade. One of the leading factors that causes the warming is known as Southern Annular Mode (SAM). SAM is described as the north to south movement of a westerly wind belt that circles the Antarctica. Forced by the westerly wind belt, the local mesoscale winds, known as Foehn winds, are frequently occurring on the east side of AP, where the Larsen ice shelves are attached to the ice sheet over AP. Once the Foehn wind event occurs, it is creating significant warming to the leeward side of AP slope due to adiabatic heating. The data we used to quantitatively explore the warming impacts of SAM and Foehn winds on the Larsen C ice shelf is the newly released ECMWF reanalysis-5 (ERA5). For the study period of 1979-2018, our study indicates that when SAM is in strong positive phase, surface temperatures over Larsen C ice shelf increase along with an increase in the Foehn wind events.
Bush, Mariah, "Southern Annular Mode, Foehn Wind, and Larsen C Ice Shelf" (2019). Undergraduate Research and Creative Inquiry Symposia. 188.