Great Lakes Fluctuations Sometimes Extreme **
Aug 24th, 2007 · All week, forecasters have been warning about the possibility of a phenomenon known as seiches along Lake Michigan. They are a common occurrence on the Great Lakes -- continuous oscillations that shift the water level, usually minutely. But in extreme cases, they can cause a huge water level drop-off -- like in July 1995, when a seiche in Lake Superior caused the water to rise and fall in the lake by 3 feet in 15 minutes, or in June 1954, when a 10-foot seiche hit Chicago's lakefront, sweeping away eight fishermen who drowned. Dr. Stephen Bortone, the director of Minnesota Sea Grant, part of the University of Minnesota, talks with Robert Siegel.