Antarctic Climate Variability and Tropical Teleconnections

Ohio State University Research Foundation -Do Not Use, Columbus OH

Investigators

Abstract

This study will combine observational analyses and three-dimensional global climate model (GCM) experiments to gain insight to the tropical teleconnections and decadal variability of the Southern Hemisphere Annular Mode (SAM). Observations show an increasing positive polarity to the SAM in recent decades denoted by an increase in intensity of the circumpolar vortex. The study will test two hypotheses: that the teleconnection of the El Nino-Southern Oscillation (ENSO) to the Antarctic region is modulated by the zonal wind structure over the Southern Hemisphere extratropics, or alternatively, that different tropical forcing leads to decadal variability in the teleconnection. As a corollary, the SAM and ENSO in turn influence precipitable water transport over the Antarctic continent, and hence the ice mass balance. A new level of understanding of the SAM and ENSO linkages to global teleconnections and global climate change will be achieved by use of both observations and GCM simulations. The observational research includes a dynamical study of the role of momentum, moisture and heat transports during the modern satellite era, and the modeling study includes GCM simulations with the National Center for Atmospheric Research (NCAR) Community Atmosphere Model version 4 (CAM4). Broader impacts of this study include contributions to the goals of the International Polar Year, as well as career development for a graduate student and a research scientist. Material for university lectures will be developed, and lectures and field trips for students from the Columbus Public Schools will be facilitated. The project will produce a webpage developed by high school students, and will archive publicly-available results at the Byrd Polar Research Center (BPRC) and the National Snow and Ice Data Center. Collaboration with BPRC's outreach coordinator will yield data and visualization activities for middle and high school students to be used by a local science-oriented public high school and by summer programs at Ohio State University.