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Cleanups planned for Coastweeks
The News-Messenger (9/2)
Ohio's 2008 Coastweeks observance will again focus on the preservation and protection of Lake Erie and its watershed through a variety of cleanup events along the shoreline and throughout its watershed.
Maritime Academy may hike maritime tuition up to 57%
Traverse City Record-Eagle (8/27)
Some of next year's students at the Great Lakes Maritime Academy could face tuition rate hikes of 50 percent or more.
Students build wind turbines
WTVG-TV Toledo (8/27)
Science students at Clay high school will soon have a way to measure the wind and how much power it can produce. This grant-funded project will provide data on how well turbines produce power in the changeable wind environment near the lake.
What's going on in your neighborhood this month? Meet other people and learn together at recreational and educational events! Our new dynamic calendar is updated daily with current educational events.
2 | Prehistoric glacial movements
Early drainage from these lakes flowed southward through the present Illinois River Valley toward the Mississippi River, through the Trent River Valley between present lakes Huron and Erie and through the Lake Nippissing-Ottawa River Valley from Georgian Bay on Lake Huron downstream to the present Montreal, Quebec, area.
Without the immense weight of the glaciers-thousands of feet thick in places- the land began to rebound. Even today, virtually all of the land in the Great Lakes basin continues to rise. Southern parts of the basin are rising slightly, less than 3 inches per century. The northeastern corner of the Lake Superior basin, however, is rebounding in excess of 21 inches per century.
Graphic: Prehistoric glacial movements and lake shapes
Since the retreat of the glaciers, water levels continued to undergo dramatic fluctuations, some in the magnitude of hundreds of feet. These extremes were caused by changing climates, crustal rebound and natural opening and closing of outlet channels. Within the last 1,000 years, evidence suggests that lake levels exceeded the range of levels recorded since 1865 by an additional five feet on lakes Michigan and Huron. As a consequence of these recent fluctuations, shoreline position and environments have dramatically changed. Dunes, baymouth barriers, embayments and river mouths have all been modified by the forces of water. Many dune formations-some hundreds of feet thick-were established during glacial periods. The tops of these dunes have been continuously sculpted by winds to form the majestic structures now visible.
Today, rebounding of the earth's crust, erosion, and changes in climate continue to alter the shapes and sizes of the Great Lakes. As one of the youngest natural features on the North American continent, the lakes remain a dynamic, evolving system.
