SATELLITE MEASUREMENTS OF SURFACE-WATER TEMPERATURE IN THE GREAT-LAKES - GREAT-LAKES COASTWATCH

This paper describes the NOAA CoastWatch program for the Great Lakes and discusses the applications and limitations of satellite-measured surface water temperature images received as a result of this program in mapping and analyzing physical features of the Great Lakes environment. The initial product of the Coast Watch program is a set of surface water temperature images derived from NOAA AVHRR (Advanced Very High Resolution Radiometer) data. These temperature maps are produced on a routine basis (usually 2-3 sufficiently cloud-free images per week) and are made available within hours of acquisition. The satellite-derived water temperatures from images acquired during the period May 1990 to May 1991 were compared to temperatures measured at NOAA weather buoys and found to be highly correlated. We found the satellite-derived temperatures were consistently 1-1.5C-degrees cooler than buoy temperatures. Root mean square deviations between buoy and satellite temperatures ranged from 0.8 to 1.6C-degrees. There was also a consistent pattern to the geographic registration errors of the images, ranging from 8.4 km westward for the NOAA 10 nighttime pass to 8.3 km northeast for the NOAA 11 nighttime pass. Potential application of the imagery to detection and location of thermal fronts, analysis of circulation patterns, and ice and snow mapping are also discussed.