Since late May 2003, the GOES-9 satellite has been operating over the western Pacific ocean, centered over the equator at 155 degrees east longitude. Each hour, radiances from both the Imager and Sounder instruments are received and utilized to produce meteorologically-useful products. From the Imager (visible band plus four infrared bands ranging from 3.9µm to 12.0 µm), Clear Sky Brightness Temperature (CSBT) imagery is generated. The GOES-9 Imager CSBT information is being offered to numerical modelers at both the National Center for Environmental Prediction (NCEP) and the European Centre for Medium Range Weather Forecasts (ECMWF). From the Sounder (visible band plus 18 infrared bands ranging from 3.7µm to 14.7µm), several different experimental products are/can be produced: retrieved atmospheric temperature and moisture profiles and retrieved cloud parameters, various derived product images from both the retrievals and cloud-top information, as well as derived ozone imagery. In terms of sounding the atmosphere from geostationary orbit, GOES-9 provides a unique opportunity never before available over this portion of the globe.

This paper will present examples of the derived data available from GOES-9. In addition, the quality of some of the data and products will be evaluated, and an effort will be undertaken to quantitatively examine the impact of the GOES-9 Sounder radiances on the corresponding retrieval first guesses, compared to the same for GOES-12 and –10 over the continental United States. More precise, albeit limited, site verifications will focus on collocated GOES-9 retrievals and radiosondes, and comparisons of GOES-9 retrievals with collocated, in-situ information provided by the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) instrument site on Nauru Island, located near the GOES-9 subpoint at 0.52 degrees south latitude, 166.91 degrees east longitude. Finally, examples of CSBT data impact on numerical forecasts will be shown, when results are available.