Topographic Effect of the Antarctic Peninsula on Strong Wind Event at the King Sejong Station

Abstract

The topographic effect on the strong wind event occurred on 7 January, 2013 at the King Sejong Station (KSJ), Antarctica was investigated using the Polar Weather Research and Forecasting (WRF) model. Numerical experiments applying three different terrain heights of the Antarctic Peninsula (AP) were performed to quantitatively estimate the topography effect on the selected strong wind event. The experiment employing original AP topography successfully represented observed features in strong wind, both in terms of peak wind speed by around 94% (~19.7m/s) and abrupt transitions of wind speed. In contrast, the experiment with a attened terrain height signicantly underestimated peak wind speeds by around 51% (~10.4m/s) of observations. An absence of AP topography failed to simulate both a strong discontinuity of sea-level pressure elds around the east coast of the AP and a strong southeasterly over the AP. As a result, the observed downslope windstorm, driven by a ow overriding a barrier, was not formed at the western side of the AP, resulting in no further enhancement of the wind at the KSJ station. This result demonstrates that the topography of the AP plays a critical role in driving strong wind at the KSJ station on 7 January, 2013, accounting for approximately 50% of the total wind speed.