Analysis of Low-Level Winds Over the Ross Ice Shelf, Antarctica: Barrier Winds Along the Transantarctic Mountains

Analysis of low-level winds over the Ross Ice Shelf, Antarctica: Barrier winds along the Transantarctic Mountains

M.A. Nigro, J.J. Cassano

Cooperative Institute for Research in Environmental Sciences, Boulder, USA; Department of Atmospheric and Oceanic Sciences University of Colorado, Boulder, USA

The steep topography surrounding the Ross Ice Shelf (RIS), Antarctica greatly influences the wind patterns in the region of the RIS. The topography provides forcing for features such as katabatic winds, barrier winds and barrier wind corner jets. These features, combined with forcing from synoptic and mesoscale cyclones that traverse the Ross Sea, can create strong, winds and contribute to a mean northward airflow across the RIS. This paper presents a wind climatology over the RIS using output from the Weather Research and Forecasting (WRF) model run within the Antarctic Mesoscale Prediction System (AMPS). The wind climatology shows the Ross Ice Shelf airstream (RAS), a dominant stream of air flowing northward from the interior of the continent over the western to central RIS to the Ross Sea, is present over the RIS approximately 34% of the time. The climatology indicates the RAS varies in both its strength and position over the RIS. This presentation will focus on the forcing mechanisms that drive the variation in the strength and position of the RAS, with an emphasis on methods to identifying barrier wind dynamics in the climatology. Future research will explore the dynamics of other forcing mechanisms responsible for the development of the RAS.