Cooperative Institute for Research in Environmental Sciences
Monday, July 11, 2011

CIRES Graduate Student wins first prize at CEDAR workshop

Chihiko Yamashita, a CIRES graduate student, won the student poster competition at the 26th CEDAR (Coupling, Energetics and Dynamics and Atmospheric Regions) workshop held June 26-July 1. Yamashita’s poster was titled “Physical Mechanisms of Gravity Wave Variations and Their Impacts on the MLT (mesosphere and lower thermosphere) during the 2009 Stratospheric Sudden Warming.” Coauthor, CIRES Fellow Xinzhao Chu, advises Yamahita in her graduate research. The most dramatic phenomenon in the winter polar stratosphere—the layer of air that lies approximately between 10 km and 50 km above the surface of the Earth—is a stratospheric sudden warming. In a single week, the temperature can increase over 25 degrees and the polar jet stream can reverse. Yamashita’s poster describes the use of models to investigate the subsequent changes that take place in the atmosphere, during this sudden warming.