Retrieval of Lake Bulk and Skin Temperatures Using Along-Track Scanning Radiometer (ATSR-2) Data: A Case Study Using Lake Tahoe, California

In 1999, four monitoring stations were permanently moored on Lake Tahoe, California-Nevada. Each monitoring station provides near-real-time measurements of the surface skin temperature and bulk temperature on a near-continuous basis. Day and night data, acquired over Lake Tahoe from March to August 2000 with the second Along-Track Scanning Radiometer (ATSR-2), have been analyzed, and sets of coefficients for recovering the skin temperature and bulk temperature of the lake have been derived. The field measurements indicate that there is a noticeable difference between the bulk and skin temperatures (skin effect), which varies over the diurnal cycle. At the time of the ATSR-2 daytime overpass, the skin temperatures are on average 0.11C cooler than the daytime bulk temperatures. At the time of the nighttime ATSR-2 overpass, the skin temperatures are on average 0.46C cooler than the nighttime bulk temperatures. The smaller skin effect during the day is attributed to strong solar heating and low wind speeds at the site in the morning.