How The Great Lakes Formed

GBF is partnering with CurrentCast to share information that they develop with other partners about water stewardship and sustainability in the Great Lakes and surrounding watersheds. CurrentCast is a project of the Center for Transformative Action based at Cornell University. CurrentCast content is owned by ChavoBart Digital Media, Inc. The Atkinson Center for a Sustainable Future at Cornell University provides scientific content support and reviews all editorial idea for the initiative.
Why Michigan’s lower peninsula is shaped like a mitten…on this CurrentCast..

Let’s go back about 14,000 years to what’s now the Great Lakes region. Back then, the entire area was covered with a sheet of ice that averaged a half-mile thick, but was up to four times that in some places.

Great Lakes

As temperatures warmed, the melting glacier moved slowly toward Canada, its massiveness gouging the land beneath it, leaving behind a handful of deep depressions.

Meltwater filled those newly created basins and…voila! The Great Lakes were born—although they didn’t take their final form for a few thousand more years.

So thanks to a glacier, we have five fantastic freshwater lakes and the familiar Michigan “mitt,” a hand-y landmark that is easily recognizable from space.

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Biodiversity & Georgian Bay

Georgian Bay Forever is working with the University of Guelph to create a library of all the aquatic species in Georgian Bay. This library will be an important tool for protecting the ecosystems in the future. Learn more.