Validation and Use of GOES Sounder Moisture Information

Abstract

The Geostationary Operational Environmental Satellite (GOES) sounders have provided quality hourly radiances and derived products over the continental United States and adjacent oceans for more than five years. The products derived from the radiances include temperature and moisture profiles; total precipitable water vapor (TPW); atmospheric stability indices, such as convective available potential energy (CAPE) and lifted index (LI); cloud-top properties; total column ozone; and midlevel motion. This paper focuses on validation and use of moisture profiles derived in clear regions. Validations are made with respect to collocated radiosondes, a microwave radiometer, and parallel runs of the regional Eta Model system. The ground-based microwave radiometer enables comparisons throughout the day, instead of only at conventional radiosonde launch times (0000 and 1200 UTC). The validations show that the sounder products provide unique information about the state of the atmosphere. The GOES sounder moisture data add information with considerably higher spatial and temporal resolution than is available from conventional radiosondes. Assimilation of three layers of moisture information retrieved from GOES sounder measurements has improved Eta Model precipitation forecasts even out to 48 h. Moreover, National Weather Service (NWS) forecasters are using GOES sounder products for a range of applications, with positive results.