Progress towards implementing an improved GOES Sounder retrieval algorithm for operations

1. Ma version is easily the poorest. OPDB Li version improves upon guess (for SD). CIMSS Li version has best SD, but does not improve on guess. All retrieval versions show a moist bias of 1 mm. CIMSS Li vers | guess OPDB Li vers | guess CIMSS Ma vers | guess Progress towards implementing an improved GOES Sounder retrieval algorithm for operations Bulk statistics over the last half year have shown that the Li version outperforms the Ma version (with improved standard deviations compared to coincident match-ups with GPS (Global Positioning System) TPW measurements). The GPS data are provided by NOAA/OAR/ESRL in Boulder (S. Gutman, D. Birkenheuer, K. Holub); close collaboration is maintained by a weekly tele-con between CIMSS-ASPB, NESDIS OPDB and OSPO, and, NOAA ESRL as monitoring of implementation and quality continues. This effort to improve the usefulness and applicability of the current GOES Sounders remains relevant, as (1) the GOES-R “legacy sounding” products will be based substantially on the (current) Li retrieval algorithm, and (2) current GOES Sounder data may continue to be available for well onto the rest of this decade. “To dream the impossible dream…” … to sound the clear atmosphere from a geostationary perspective with an infrared, limited filter wheel radiometer and provide useful profile information on moisture, stability, and/or temperature that would correct first-guesses, when poor, and positively impact weather forecasts. GOES-13 Sounder retrieval and first-guess TPW compared to GPS TPW for 01 Sep 2011 through 27 Mar 2012 The real-time GOES Sounder products that are provided to the National Weather Service (NWS) today (April 2012) are derived from the retrieval algorithm of Ma et al (1999). An improved algorithm developed at CIMSS (Coop Inst for Meteorological Satellite Studies) following the work of Li et al (2008) was provided to NOAA/NESDIS/STAR/SMCD/OPDB. Products derived from this retrieval algorithm, such as total precipitable water (TPW) and Lifted Index, have been generated at both CIMSS and OPDB for a couple years, and were monitored through 2011 to establish correct implementation at OPDB. In the fall of 2011, the OPDB code was provided (by A. Allegrino) to the NOAA/NESDIS/OSPO SPB (A.K. Sharma and team) to implement for NESDIS Operations, and thus, provide to the NWS, in AWIPS, replacing the old Ma version products. Presentation to the SPSRB (Satellite Products and Services Review Board) is planned for June 2012. Although the Li version is a clear improvement, over the Ma version, for the NWS, the improvement of the Li version with respect to the first-guess remains a difficulty. Statistics continue as one measure of success, but more effort must also be put into case studies, where the temporal and spatial advantages of GOES data may be more readily realized.