Great Lakes
Category: Geology
The Great Lakes that we know today were formed at the end of the last Ice Age, approximately 12,000 years ago. The Great Lakes are all linked via various rivers, canals and locks.
The total surface area of the Great Lakes is around 92,000 square miles. They hold a whopping 5439 cubic miles of water. There are around 35,000 islands in the Great Lakes. The largest island in the Great Lakes is Manitoulin Island of Lake Huron, the largest island located in any inland body of water. Manitoulin Island has several lakes itself, like Lake Manitou; that lake is the largest lake located on a freshwater island.
What’s In a Name?
The Great Lakes are sometimes called the Great Lakes of North America or the Laurentian Great Lakes. The latter name comes from the Laurentide ice sheets from which they were formed as the melt water of the glaciers filled the massive crags in the Earth.
They are so large that they are sometimes called inland seas. Their large surface area and depth means that the winds cause regular water level shifts of several feet, though they do not actually have tides. The Great Lakes do see waves of ten to thirty feet, though the record on Lake Superior was 51 feet.
The Great Lakes Basin eventually pours out the water from the Great Lakes to the St. Lawrence River.
Lake Superior
Lake Superior is the greatest of the Great Lakes. It has the largest surface area of any lake in North America and ranks third in that dimension in the world. The Great Lakes contain one fifth of the world’s readily available fresh water, meaning the fresh water in lakes and streams but not locked up in the polar ice caps and glaciers. Of the massive amount of water in the Great Lakes, half of it is in Lake Superior.
Lake Superior has the highest elevation of any Great Lake (about six hundred feet above sea level), greatest depth (1300 feet), best visibility and least pollution.
Lake Michigan
Lake Michigan is the largest freshwater lake contained in a single country. The rest of the Great Lakes are bi-national, with least part of each being in Canada’s jurisdiction.
Lake Michigan has the second greatest depth and second highest elevation of the Great Lakes.
Green Bay is part of Lake Michigan, separated from the lake by the Door Peninsula. Green Bay is best known for being the home of the Green Bay Packers, the only community owned major sports franchise in the United States.
Lake Michigan’s name comes from a local tribe’s word for great sea.
Lake Huron
Lake Huron is sometimes called Michigan-Huron. Lake Michigan and Lake Huron are essentially one lake except for the dividing line humans have drawn on maps at the Straights of Mackinac. Lake Huron is also connected to Lake St. Clair via the St. Clair River.
Lake Huron is connected to Lake Superior by the Soo Locks along St. Mary’s River.
Lake Huron has a very large fishing industry, and the area along the Saginaw River that drains into Lake Huron is heavily farmed.
Lake Erie
Lake Erie has the smallest water volume of the five Great Lakes. It has a shallow average depth of 62 feet. Lake Eerie is connected to the Lake St. Claire via the Detroit River.
Lake Erie’s name comes from the Erie tribe; that name comes from the word meaning long tail in Iroquois.
Lake Ontario
Lake Ontario has the smallest surface area of the five Great Lakes and is the second smallest by volume. It also has the lowest elevation at 246 feet above sea level. Lake Ontario is so much lower than the others that it is separated by the Niagara Escarpment, which limited natural navigation from there to the other Great Lakes. The Welland Canal now connects Lake Eerie to Lake Ontario.
The lakes other than Ontario are sometimes called the Upper Great Lakes.
Lake Ontario drains into the St. Lawrence River that eventually empties into the Atlantic Ocean.
Lake Ontario comes from a Huron word for lake of shinning waters.
Trivia
The Great Lakes together hold over 80% of North America’s surface fresh water.
While the Great Lakes region only accounts for 7% of American Farm production, it accounts for 25% of Canadian agricultural production.
About one in ten Americans lives around the Great Lakes, mostly on the southern side in cities like Chicago and Milwaukee. Almost a third of the Canadian population lives on their northern shore.