GOES-VAS Simultaneous Temperature-Moisture Retrieval Algorithm

Abstract

Vertical soundings of temperature and moisture derived from the GOES VISSR Atmospheric Sounder (VAS) measurements have been produced operationally since summer 1987 at the VAS Data Utilization Center (VDUC). The algorithm which was developed for the VDUC is described here in detail. Tunable features are identified, and their sensitivities are shown. The algorithm is used to process a case study for 6 March 1982 to examine its capability in a rapidly evolving weather pattern. Weaknesses are exposed, in particular the bias errors in the retrievals and the dependence on first guesses, but strengths are also evident, namely, the capacity to refine gradients and patterns in a manner which improves the first guesses.