The Great Lakes

The North American Great Lakes are seeing record low water levels — lower than at any time in the last 35 years. Since 1997, above normal temperatures have been increasing evaporation and decreasing the inflow from tributaries. In addition, below average winter precipitation has meant the lakes haven't received their normal "re-charging" from spring snowmelt, and higher winter temperatures have decreased ice cover, which normally prevents evaporation. Below average water levels have had a negative impact on shipping in the Lakes, with many carriers being forced to reduce the volume of goods they put in their ships.

This MODIS image from May 15, 2002, shows developed and undeveloped areas around Lake Huron (center), Lake Erie (below) and Lake Ontario (right). At the southwestern end of Lake Huron, the state of Michigan intrudes slightly, creating Saginaw Bay on the left. The pale areas rimming the Bay and extending down into the peninsula are wetland areas. Only a small percentage of the vast wetlands that existed around the Great Lakes before settlement remain today. Estimates range from two thirds to a full 90% of the region's original wetlands — marshes, swamps, bogs and fens — have been drained and filled to create land suitable for agriculture, development and recreation.

Several large cities are evident around the Lakes, including Detroit (between Lake Erie and the smaller Lake St. Clair), Toledo (western end of Lake Erie), Cleveland (southern shore of Lake Erie), and Buffalo (eastern tip of Lake Erie). On the northwestern shores of Lake Ontario, the city of Toronto is evident. Each of the cities appears as a grayish cluster of pixels because of the urban landscape.

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Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

Published May 22, 2002
Data acquired May 15 - 15, 2002

Source:

Terra > MODIS