I propose to provide comprehensive microphysical modeling and analysis of polar stratospheric clouds (PSCs) in support of the CALIPSO satellite, and to be a member of the CALIPSO science team. The multiwavelength backscatter and depolarization observations made by the CALIOP lidar on board CALIPSO will provide a unique and valuable set of measurements of PSC characteristics. Comparisons of CALIPSO measurements with model results will enable analyses of the microphysics responsible for the observed PSC characteristics. The Integrated MicroPhysics and Aerosol Chemistry on Trajectories (IMPACT) model has a proven ability to reproduce observed PSC characteristics, and its ability simulate winter-long vortex-wide evolution and test multiple PSC formation scenarios is ideal for the large-scale statistical intercomparison necessary for comprehensive interpretation of the CALIPSO PSC dataset. The proposed research will determine the overall mechanisms responsible for PSC formation, and furthermore quantify the parameters that control these mechanisms. Improved simulations of denitrification, dehydration, and ozone loss will be enabled, all of which will be validated by comparison with the simultaneous measurements made by other instruments in the A-train suite of satellites.
The proposed PSC modeling and analysis directly responds to the research announcement�s request for "scientific investigations in support of modeling and analysis of CALIPSO and CloudSat data toward a goal of improved understanding of clouds and aerosols in the Earth System." The CALIPSO web site specifically requests scientific data analysis of polar stratospheric clouds, in particular "studies to characterize the distribution, properties, and lifecycles of polar stratospheric clouds." Through the proposed intercomparisons with other PSC-related measurements made by A-train satellites, this proposal also responds to the announcement�s request for multiinstrument, multiplatform investigations. This research supports the NASA strategic objective of "Conduct a program of research and technology development to advance Earth observation from space, improve scientific understanding, and demonstrate new technologies with the potential to improve future operational systems." The improved understanding of PSCs that will result from the proposed research will allow assessment models to better predict the recovery the Earth's ozone layer, specifically addressing NASA's goal of being able to "predict global distribution of stratospheric and tropospheric ozone to within 25% by 2014."
