Coupled whole atmosphere-ionosphere data assimilation in WACCM-X

The recently developed Whole Atmosphere Community Climate Model eXtended version (WACCM-X) extends from the surface to the upper thermosphere (~400-700 km), including a fully coupled ionosphere with self-consistent electrodynamics. WACCM-X enables the study of ionosphere-thermosphere variability due to both lower atmosphere as well as solar processes within a self-consistent framework. To study, and possibly predict, the upper atmosphere variability we have added the data assimilation capability to WACCM-X using the Data Assimilation Research Testbed (DART) ensemble Kalman filter. The initial development of WACCMX+DART has focused on the assimilation of observations up to the lower thermosphere (~100 km). Despite only assimilating lower-middle atmosphere observations, we demonstrate that WACCMX+DART is suitable for generating analyses of the ionosphere variability during the 2009 sudden stratosphere warming (SSW) time period. Preliminary results illustrating the use of WACCMX+DART to forecast the ionosphere variability during the 2009 SSW, and the incorporation of COSMIC electron density profile observations into the assimilation will also be presented.