[AAS08-06] Investigating the missing gravity wave drag in the Southern Hemisphere via satellite observations
★Invited Papers
Keywords:gravity waves, ozone, satellite observations
Recent assessments of chemistry-climate models (CCMs) reveal biases in temperatures and winds in, especially but not limited to, the Southern Hemisphere stratosphere, where winds are generally too strong and temperatures too cold. The reasons for these biases are not completely understood, but it is thought that missing gravity wave drag in models is a major culprit. Understanding the sources of the missing drag and correcting the deficiencies in modeled gravity wave effects is a high priority since the resulting model biases in wind and temperature hinder our ability to realistically model the ozone hole and its recovery, which also has implications for our ability to model tropospheric climate change. However, observational constraints on gravity wave parameterizations have remained difficult to establish. In this presentation we show results using the High Resolution Dynamic Limb Sounder (HIRDLS) to investigate the missing drag in the Southern Hemisphere. We derive detailed gravity wave properties and obtain new observational estimates of the gravity wave drag in the stratosphere to guide gravity wave parameterizations in CCMs.