Department of Atmospheric and Oceanic Sciences, University of Wisconsin-Madison
Assimilation of hyperspectral infrared sounder radiances under cloudy skies in a regional NWP model
Room 823 AOSS, April 25, 2016, 9:40 AM
Satellite measurements are an important source of global observations in support of numerical weather prediction (NWP). Good clear detection of satellite radiance assimilation could effectively remove the cloud contamination and keep the clear observations for assimilation. The clear pixel detection method is applied in this study. The clear pixel detection method is collocating the cloud mask from high spatial resolution imager data to help IR cloud detection. With the clear pixel detection, a cold bias and a wet bias are removed from the analysis fields. The cloud-clearing method extracts the clear portion of FOV and gets the clear equivalent radiances. The assimilation of cloud-cleared radiances is an alternative way to use the thermodynamic information under partially cloudy regions. Assimilating the cloud-cleared radiances adjusts the atmospheric environmental fields and improves the hurricane track forecasts substantially.