Tuesday, 24 January 2012: 11:15 AM
Whole Atmosphere Model (WAM): Connecting Terrestrial and Space Weather
Room 252/253 (New Orleans Convention Center )
A new generation of numerical weather prediction models connecting terrestrial and space weather has emerged over the last decade. With applications to space weather prediction in mind, WAM is built on National Weather Service's operational weather prediction Global Forecast System (GFS) extended from its nominal top altitude of 62 km to about 600 km. The model extension into a domain of highly variable composition, high temperatures, and very low density requires certain generalization of the common meteorological model framework. It incorporates relevant physical processes including those responsible for the generation of tidal and planetary waves in the troposphere and stratosphere. In the absence of artificial boundaries within the model domain these waves freely propagate into the upper atmosphere, exponentially growing in amplitude to eventually dissipate by ion drag, viscosity, and heat conduction. Interactions of tides with ion drag in particular play an important role in the formation of long observed space weather phenomena such as the midnight temperature and density maxima (MTM and MDM) and the attendant wind variability. Model diagnostics and simulations will be presented and compared with recent observational climatologies.