Study: Climate change altering Great Lakes water levels

Muskegon Chronicle (Michigan): A new study blames a post-1998 plunge in upper Great Lakes water levels on changing climate patterns -- not a manmade "drain hole" sucking lake water out the St. Clair River. So there's no need to plug the leak ... for now. But global warming might make a St. Clair fix necessary in the future. Those are the preliminary conclusions of a draft report published recently as part of a massive study of Great Lakes water levels.

West Michigan residents will have a chance to hear scientists present their findings, and to ask questions and offer comments, at a public meeting Tuesday in Muskegon. "We'd like to see a broad range of people come out ... property owners along the lake, boaters, people who are concerned about the environment, people whose livelihoods may depend on the lakes," said John Nevin, spokesman for the agency that sponsored the study.

…The report is the first fruit of a five-year study by the International Joint Commission, a U.S.-Canadian panel that mediates Great Lakes issues and recommends governmental actions. The $15 million International Upper Great Lakes Study is examining whether actions are needed to stabilize water levels in lakes Michigan, Huron and Superior.

…The just-released study examines one of the major lake-level issues: Whether earlier dredging in the St. Clair River led to the post-1998 plunge by creating an excessively large "drain hole," possibly requiring construction of a structure in the river to control water flow. Lakes Michigan and Huron drain into the St. Clair River, which flows into the Detroit River and Lake Erie.

…A much bigger factor was a change in climate patterns, with warm, dry weather prevailing in the Michigan-Huron basin starting in the 1990s, the scientists found. …

North shore of Lake Superior