RUI: Solid/Liquid Phase Diagrams of Stratospheric and Upper Tropospheric Importance

Wisconsin Lutheran College, Milwaukee WI

Investigators

Abstract

This RUI project is an investigation of the thermodynamics of polar stratospheric clouds (PSC's). There is strong evidence that PSC's play an important role in the annual depletion of stratospheric ozone at the poles. The chemical activity of PSC particles changes as a function of their physical state (solid or liquid) and their chemical composition. This research project will investigate the solid/liquid phase diagrams of aqueous chemical systems that make up PSC's using differential scanning calorimetry and infrared spectroscopy. The systems to be investigated include the nitric acid/water binary system and the nitric acid/sulfuric acid/water ternary system. The results will have implications for understanding and modeling heterogeneous reactions that affect stratospheric ozone.