Dear Tom,
You indicated that the water level in Lake Michigan has risen 7 inches since July 2007, and that rise added 2.73 trillion gallons of water. What happens at the evaporation end? How much water evaporates from Lake Michigan?
— Carl Gaines
Dear Carl,
Atmospheric processes operate on a scale that boggles the mind, and the evaporation of water from Lake Michigan is no exception.
Lake Michigan’s 22,300 square miles of surface area loses 29.5 inches of water annually via evaporation. That loss works out to a staggering 11.51 trillion gallons of water per year, or a daily average of 31.5 billion gallons (this sentence as published has been corrected in this text).
Here’s the actual number: 31,500,000,000 gallons of water lost to the atmosphere from Lake Michigan daily via evaporation (this sentence as published has been corrected in this text).
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