Climate Chage

The Great Lakes have been a bastion of stability, with water hovering at about the same level for as long as anyone can remember. But, according to a report in Discovery News, a new study shows that climate change once pushed lake levels far below where they are now. That opens up the possibility that future climate change might do the same thing. More than 33 million people depend on the Great Lakes for water, hydropower and work in industries ranging from shipping to recreation. During the past event, about 8,500 years ago, water ceased to flow between the lakes. Today, going from interconnected bodies of water to isolated basins could be catastrophic.

For decades, scientists have been working to reconstruct the aqueous history of the Great Lakes. Those reconstructions showed that, for thousands of years, lake levels have only varied by a couple of meters up or down, mostly due to the advance and retreat of glaciers, which alternately trap and release water. As they move, glaciers also cause land underneath them to rise and fall slightly.