Collaborative Research: Atmospheric Data Assimilation Techniques for Antarctic Applications

Ohio State University Research Foundation -Do Not Use, Columbus OH

Investigators

Abstract

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)." The paucity of conventional meteorological observations over the Antarctic continent represents a major challenge to both weather forecasts and climate analysis. This puts a premium on the productive use of satellite data, including non-traditional approaches such as is exemplified by the GPS radio occultation (RO) soundings, currently available from the joint Taiwan/US COSMIC/FormoSat-3 mission. This polar orbiting constellation of 6 low earth orbiting platforms (LEOs) uses RO limb sounding of the atmospheric refraction of the global positioning satellite network signals to yield, amongst other things, atmospheric soundings of temperature, pressure and moisture content of the atmosphere at high spatial and temporal resolution. Given the virtual total lack of radiosonde data over the Southern Ocean and the Antarctic continent, methods to most productively utilize this powerful observing system are of interest to researchers and observational groups alike. Investigators from NCAR and the Ohio State University propose to develop effective and efficient data assimilation approaches to incorporating COSMIC RO soundings into Antarctic weather prediction and other atmospheric (e.g. climate and atmosphere system variables) data records. Existing 3 or 4 dimensional variational (3/4D-Var) and ensemble based (i.e. probabalistic) data assimilation schemes will be used in conjunction with the Weather Research and Forecast (WRF) model in order to specify which data assimilation scheme is best suited to weather analysis, and reanalysis, in the Antarctic and Southern Ocean atmospheric environments.