The Variability and Predictability of the Amundsen / Bellingshausen Seas Low and its Connection to the Regional Antarctic Climate

Ohio University, Athens OH

Investigators

Abstract

Abstract This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The West Antarctic Peninsula (WAP) is the one region of the Antarctic continent that is unequivocally warming, and as such is associated with the mobilization and loss of major ice shelves, as has been recently observed for the Larsen B (2002) and Wilkins Ice Shelf (2008). The Amundsen/Bellingshausen Seas Low (ABSL) is a sub-synoptic, often persistent low-pressure weather system that leads to sustained west-northwesterly airflows across the WAP region. Long term changes in the strength and position of the ABSL, its teleconnection with large scale climate modes such as the Southern Annular Mode (SAM) and the El-Nino Southern Oscillation (ENSO), and its interaction with the polar vortex are suspected to be important factors in attribution of Antarctic climate change currently being dramatically observed in the WAP. Because of the paucity of reliable observations in this extremely remote area of the continent, much remains that is uncertain Existing satellite-era observational data (since 1979), along with reanalysis sets, will be examined to shed better definition of the variability in position and intensity of the ABSL as a weather feature. Several modeled data sets, from a range of mesoscale and climatological models (e.g. Polar MM5, AMIP, CCM CAM3, HadAM3, ECHAM4.5) will also be examined at the regional scales appropriate to the ABSL to better describe the large scale influences of climate patterns such as ENSO and SAM. Finally an assessment of the effects variability in the ABSL may have on the regional West Antarctic climate will be made.