What do you know about Lake Michigan?. "Michi-gama" "large lake”

What do you know about What do you know about Lake Michigan?Lake Michigan?

"Michi-gama" "Michi-gama" "large lake” "large lake”

How were the Great Lakes How were the Great Lakes formed?formed?

• The Great Lakes were formed nearly 20,000 The Great Lakes were formed nearly 20,000 years ago when the earth's climate warmed years ago when the earth's climate warmed and the last glacial continental ice sheet and the last glacial continental ice sheet retreated. The glacier, up to 2 miles thick, retreated. The glacier, up to 2 miles thick, was so heavy and powerful it gouged out the was so heavy and powerful it gouged out the earth's surface to create the lake basins. earth's surface to create the lake basins. Meltwater from the retreating glacier filled Meltwater from the retreating glacier filled the newly created basins. Approximately the newly created basins. Approximately 3,500-4,000 years ago, the Great Lakes 3,500-4,000 years ago, the Great Lakes attained their modern levels and area.attained their modern levels and area.

What a Relief!What a Relief!

• With the weight of the heavy glaciers With the weight of the heavy glaciers gone, the bed of the Great Lakes gone, the bed of the Great Lakes continues to rise at a rate of 7.5 cm continues to rise at a rate of 7.5 cm every 100 years!every 100 years!

Lake Michigan Water LevelsLake Michigan Water Levels• http://www.doorcountyadvocate.com/article/20130109/ADV01/301090304/Lake-Michigan-sets-new-record-low

Great Lake FactsGreat Lake Facts

• The Great Lakes have 90% of US fresh water, The Great Lakes have 90% of US fresh water, and 18% of the worlds fresh water (and 18% of the worlds fresh water (only the polar only the polar ice caps hold more of the worlds fresh waterice caps hold more of the worlds fresh water).).

• Provides drinking water for 40 million people. Provides drinking water for 40 million people. Provides 56 billion gallons of water per day for Provides 56 billion gallons of water per day for municipal, agricultural, and industrial use. municipal, agricultural, and industrial use.

• Spread evenly across the contiguous 48 states, Spread evenly across the contiguous 48 states, the lakes' water would be about 9.5 feet deep. the lakes' water would be about 9.5 feet deep.

Great Lakes Watershed

Covers an area the size of France

The The Lake Lake Michigan Michigan basinbasin is the is the area of land area of land where rivers where rivers and streams and streams all drain into all drain into Lake Michigan. Lake Michigan.

• 37 million people live in this area37 million people live in this area• Chicago processes almost a billion Chicago processes almost a billion

gallons of Great Lakes water each gallons of Great Lakes water each DAY! DAY! Wastewater is sent to the Gulf of MexicoWastewater is sent to the Gulf of Mexico

• Only 1% of the water in the Great Only 1% of the water in the Great Lakes system is replenished each Lakes system is replenished each year; the remaining is a one time gift year; the remaining is a one time gift from the glaciers.from the glaciers.

• The Chicago Sanitary & Ship Canal The Chicago Sanitary & Ship Canal drains 2.1 billion gallons of water drains 2.1 billion gallons of water from the Lakes into the Gulf of from the Lakes into the Gulf of Mexico every day!Mexico every day!

Lake Michigan FactsLake Michigan Facts

• Lake Michigan is the third largest of Lake Michigan is the third largest of the Great Lakes and ranks as the the Great Lakes and ranks as the fifth largest lake in the world. fifth largest lake in the world.

• Deepest Point is 923 feet Deepest Point is 923 feet

• Lake Michigan beach closingsLake Michigan beach closings– 2003 – 1,4732003 – 1,473– 2002 – 9192002 – 919– 1996 – 182 1996 – 182

• Deepest Point Deepest Point – 923 feet 923 feet

Lake Effect WeatherLake Effect Weather• Keeps Chicago Keeps Chicago

– Cool in the summerCool in the summer– Warm in the winterWarm in the winter

• Lake Effect SnowLake Effect Snow

Invasive SpeciesInvasive Species• Since the 1800s, more than 160 Since the 1800s, more than 160

aquatic invasive species have aquatic invasive species have become established in the Great become established in the Great Lakes.Lakes.