RUI: Gravity Waves and the Stratospheric Polar Vortex

Coastal Carolina University, Conway SC

Investigators

Abstract

Gravity waves provide important coupling between the lower atmosphere and the stratosphere. Intense wintertime synoptic disturbances that significantly enhance the jet stream curvature and promote suitable flow over topography can excite strong gravity waves that propagate into the stratosphere, where they can modify the strength of the polar vortex. Thermal perturbations induced by gravity waves can trigger the formation of polar stratospheric clouds in the lower stratosphere - such clouds participate in the catalytic destruction of ozone. This project will characterize the sources and properties of wintertime gravity waves in the polar regions and their propagation into the stratosphere and will assess the interactions between gravity waves and the polar circulation. Numerical simulations of gravity-wave events up to the stratopause will be performed using a high-resolution weather forecasting model that has been modified for this study. Simulated gravity waves will be compared with satellite observations will allow the characterization and improved understanding of wave properties, sources and propagation. Gravity-wave influences on the polar vortex will be estimated and the roles of gravity waves in the formation of polar stratospheric clouds will be explored. These studies will help constrain how gravity-wave effects can be incorporated into global climate models, thereby improving the effectiveness of these models for assessing climate evolution and ozone variability. Activities carried out under this Research at an Undergraduate Institution (RUI) project will enrich undergraduate education inside and outside the classroom. Newly obtained project results and model experiments will be incorporated into courses. Undergraduate researchers will work with collaborating scientists, conduct modeling experiments, analyze model output and observational data, and present research results. In so doing, they will participate in cutting-edge geophysical research that is generally unavailable at similar state-supported liberal arts institutions and that will be unique within the region.