Will the rising ocean levels affect the Great Lakes?

This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated.

Dear Tom,

Will the rising ocean levels affect the Great Lakes?
— William Stolley, Burlington, Wis.
Dear William,
The world’s oceans have been rising at an average rate of 0.13 inches per year during the past 20 years, a rate about twice the rate of the preceding 80 years. The rise occurring now is expected to increase in future years because of thermal expansion of water as it warms (the oceans are gradually warming, and warming water expands slightly as its temperature increases) and because of increasing amounts of water collecting in the oceans as a result of land-based ice melting.
The Great Lakes, however, are land-locked bodies of water (that drain via the St. Lawrence River into the Atlantic Ocean) and are not influenced by the rising oceans. The levels of the Great Lakes fluctuate a few feet in cycles that are independent of ocean levels.

Notice: you are using an outdated browser. Microsoft does not recommend using IE as your default browser. Some features on this website, like video and images, might not work properly. For the best experience, please upgrade your browser.