The Arctic polar stratosphere and mesosphere during IPY

The International Polar Year (IPY) is an international scientific program focused on intensive observations in the Arctic and Antarctic between March 2007 and March 2009. As part of this effort, we have established a web site (http://research.iarc.uaf.edu/IPY-CTSM/index.php) to show near-real time monitoring of the Arctic troposphere, stratosphere, and mesosphere. A network of five Rayleigh lidars (i.e., Kühlungsborn, Germany (54°N, 12°E), Chatanika, USA (65°N, 147°W), Kangerlussuaq, Greenland (67°N, 51°W), Andoya, Norway (69°N, 16°E), and Eureka, Canada (80°N, 86°W)) has measured middle atmosphere temperature profiles at high vertical resolution. We combine these lidar data with satellite observations and meteorological re-analyses data to study the structure, evolution, and variability of the Arctic stratospheric vortex and Aleutian anticyclone during the winter of 2007-2008 and 2008-2009. The lidar measurements show considerable variation in the vertical temperature structure from night-to-night. Variability is directly related to whether the vortex or anticyclone is sampled. Three-dimensional animations of the Arctic vortex and anticyclones illustrate the evolution of the large-scale circulation and the structure of the stratopause during major stratospheric warming events in February 2008 and January 2009.