Asynchronous Assimilation of High Temporal Infrared Imaging for Wind Profile Retrieval – A Pilot Study

High temporal infrared satellite observations not only provide three dimensional temperature and moisture; they also provide information of wind through humidity tracer advection from high temporal coverage. Adjustments of mass fields of the atmosphere can also influence wind field through balance constraints build into the data assimilation system. Direct assimilation of these radiance observations over a time window in a 4DVAR assimilation system can have both direct and indirect impacts on the wind analysis. The assimilation system can adjust the wind field of the initial conditions during minimization to derive an optimal analysis Peubey and McNally (2009) investigated the impact on wind analyses from assimilating clear sky radiances from two water vapor channels on Meteosat-9 using the ECMWF 4DVAR system. They found positive impact on wind analysis throughout the troposphere with best results at 300 and 500 hPa. The advection of humidity tracer, which provides information of flow, is the main mechanism for improvement of wind analyses from assimilating clear sky radiances. In this early stage of a pilot study, different permutations of assimilation experiments for 4DVAR wind profile retrieval using different WRF DA model spatial resolution, assimilation window, and AHI, the ABI proxy, infrared data frequency are to be demonstrated.