A Multidecadal Analysis of Fohn Winds over Larsen C Ice Shelf from a Combination of Observations and Modeling

作者：Wiesenekker Jasper M^*; Munneke Peter Kuipers; van den Broeke Michiel R; Smeets C J P Paul

来源：Atmosphere, 2018, 9(5): 172.

DOI：10.3390/atmos9050172

• Fohn
• Antarctic Peninsula
• Larsen ice shelf
• multidecadal analysis
• automatic weather station
• regional climate model

The southward progression of ice shelf collapse in the Antarctic Peninsula is partially attributed to a strengthening of the circumpolar westerlies and the associated increase in fohn conditions over its eastern ice shelves. We used observations from an automatic weather station at Cabinet Inlet on the northern Larsen C ice shelf between 25 November 2014 and 31 December 2016 to describe fohn dynamics. Observed fohn frequency was compared to the latest version of the regional climate model RACMO2.3p2, run over the Antarctic Peninsula at 5.5-km horizontal resolution. A fohn identification scheme based on observed wind conditions was employed to check for model biases in fohn representation. Seasonal variation in total fohn event duration was resolved with sufficient skill. The analysis was extended to the model period (1979-2016) to obtain a multidecadal perspective of fohn occurrence over Larsen C ice shelf. Fohn occurrence at Cabinet Inlet strongly correlates with near-surface air temperature, and both are found to relate strongly to the location and strength of the Amundsen Sea Low. Furthermore, we demonstrated that fohn occurrence over Larsen C ice shelf shows high variability in space and time.

• 出版日期2018-5