Surface and vertical temperature data will be obtained from several large lakes with surface areas large enough to be effectively sampled with AVHRR imagery. Yearly and seasonal patterns of surface and whole water column thermal values will be compared to estimates of surface temperature obtained from NOAA Coast Watch Imagery for those lakes for the period of time where concurrent imagery and in situ data exist. The lakes chosen for this study will include lakes with a varying surface area to depth ratios, salinities, and geographic locations. Large shallow lakes are relatively well mixed and are more likely to be isothermal over their depth. Lakes with relatively smaller surface area to depth ratio (very deep lakes) are expected to be highly stratified and heterogeneous in temperature. Salinity and geographic location are also important factors in determining the thermal regime of a lake. Examples of large shallow lakes include Oneida Lake, New York; Lake Okeechobee, Florida; and the Salton Sea, California. Examples of very deep lakes include Pyramid Lake, Nevada and Lake Tahoe, California. The Salton Sea and Pyramid Lake are examples of high salinity systems. The comparison of seasonal values of surface temperature derived remotely from AVHRR imagery with surface and whole water column values will allow for an assessment of the ability of AVHRR imagery to accurately estimate changes in lake thermal values over time.

"July 2000." Includes bibliographical references-p. 32-37." "EPA 600-R-00-012." Cover title.