An assessment of the GOES-VISSR for determining lake ice breakup dates: Implications for operational monitoring
We analyzed 1830 visible band (0.54-0.70 -tm) Geostationary Operational Environmental Satellite Visible and Infrared Spin-Scan Radiometer (GOES-VISSR) scenes to derive lake ice breakup dates for 81 selected lakes and reservoirs from 1980 to 1994 in the U.S. upper Midwest and portions of Canada (60°N, l05°W to 40°N, 85 °W). This image processing was intrinsic to a study of lake ice breakup patterns as indicators of climate change in the mid- to high latitudes, the spatiotemporal domain in which temperature increases due to enhanced greenhouse wanning are generally predicted to be greatest. Visual interpretation was performed in a temporal context, in which ice-off dates were determined relative to ice conditions on proximate days. Major constraints were cloud cover, poor spatial resolution and spectral information of the GOES-VISSR, and difficulty in distinguishing bare ice from open water. Comparison to available ground-derived ice breakup dates revealed a mean absolute difference of3.2 days and a mean difference of -0.4 days. A metadata data base was compiled containing summary information and reduced versions of the GOES-VISSR images for future reference. Our results indicate that the date of lake ice breakup can be reliably determined from GOES-VISSR data and is inherently amenable to operational monitoring.