Surface Temperature Fronts in the Great Lakes

摘要: The distribution and variability of surface temperature fronts in the Great Lakes is studied using an 11 year time series (1985 to 1995) Advanced Very High Resolution Radiometer (AVHRR) images. After removal cloud contaminated pixels as well those potentially ice covered, edge detection algorithm identifies each image. probability detecting a front highly variable from lake seasonally. Fronts during winter months generally have cold water on their shallow side appear progressively deeper progresses. properties are consistent with formation mechanism involving strong cooling over sloping bottom. A spring transition occurs, whereby these disappear replaced by nearshore thermal bar warm found side. this depends upon lake, occurring first Lake Erie, next Ontario, Huron, Michigan, finally Superior. These also observed progress slowly into waters warm. classical (4°C) seen all lakes but most peak frontal activity temperatures greater than 4°C, suggesting that marks offshore more extensive zone. Frontal declines summer except