| Theory Investigation: | Studies of Water Vapor Sources for the Lowermost Stratosphere and Meteorological Field Support for the SAGE III Ozone Loss and Validation Experiment (SOLVE) |
| Principal Investigator: | Henry B. Selkirk |
| Organization: | Space Physics Research Institute Mail Stop 245-5 Ames Research Center National Aeronautics and Space Administration Moffett Field, CA 94035-1000 |
| Co-Investigator: | Leonhard Pfister |
| Organization: | Mail Stop 245-5 Atmospheric Chemistry and Dynamics Branch Ames Research Center National Aeronautics and Space Administration Moffett Field, CA 94035-1000 |
Investigation Description: The central scientific focus of our theoretical investigations is the origin and evolution of the water vapor content of near-tropopause air parcels along the flight paths of the DC-8 and the ER-2 during the SOLVE field mission. We will also contribute to the SAGE-III validation effort by using trajectory analyses to translate airborne platform observations of water vapor into the SAGE-III flight path. During the SOLVE field campaign, we will provide full-time meteorological support to each of the three DC-8 field with forecasting and scientific data products.
Our approach in our investigations of lower stratospheric water vapor content is to use mixing line analyses and convective history calculations to determine the convective or isentropic exchange processes by which water vapor values are set upon entry to the lowermost stratosphere upstream of the ER-2 and DC-8 flight paths. Particular attention will be paid to unusually elevated levels of water vapor which play a role in recent theories of chlorine activation on lower stratosphere ice clouds as well as wave cloud cooling events far downstream from stratospheric parcel entry points. Such studies will contribute to several scientific issues of direct relevance to SOLVE. These include understanding the initial state of trace constituents as the polar vortex sets up in the early winter, the processes by which chlorine is activated and leads to ozone loss, and the influence of water vapor levels on aerosol formation near the tropopause.