Saturday, August 18, 2007

The Shrinking Lake Superior

About a month ago, I read this story about the declining water levels in Lake Superior. The water has been going down for years, and as noted in the article, locals believe the government is stealing the water to aid in the expansion in the southwest. This view seems to be held by locals in Canada as well. Scientists and the Army Corps. of Engineers dispute this theory.

However, the water keeps going down as reported by the National Oceanic & Atmospheric Administration (NOAA) yesterday:
NOAA hydrologists indicate that Lake Superior is nearing record lows for the month of August, a trend that if continued could break past record lows for the months of September and October.
The big lake they call Gitche Gumee going dry? How can this be? Well, the NOAA provides their answer:
The lake has been decreasing by a rate of 10 mm every year since 1978, and has dropped a dramatic two feet during the last decade. The Great Lakes region has been experiencing warmer winters since 1997, and the combination of warmer air temperatures and less ice cover leads to increased evaporation rates during the winter. Also, with less snow pack, there is less spring runoff to replenish the lakes.

[snip]

Lake Superior’s record low of 182.69 meters was set in April 1926, the same year the lake reached an averaged annual record low of 182.90 meters as a result of a major climatic event that led to the dust bowl. Sellinger said that dramatic water level changes are generally caused by major climatic events.
The dust bowl caused the widespread economic and environmental hardship that inspired both The Grapes of Wrath and the song "My Oklahoma Home", which was recently covered by Bruce Springsteen and the Seeger Sessions Band. Not a pleasant time by any stretch of the imagination.

A few years ago, NASA scientists published their findings about how the "major climatic event" causing the dust bowl and drop in Superior happened.
The study found cooler than normal tropical Pacific Ocean surface temperatures combined with warmer tropical Atlantic Ocean temperatures to create conditions in the atmosphere that turned America's breadbasket into a dust bowl from 1931 to 1939.

[snip]

"The 1930s drought was the major climatic event in the nation's history," Schubert said. "Just beginning to understand what occurred is really critical to understanding future droughts and the links to global climate change issues we're experiencing today."
Part of those global climate change issues the folks at NASA are talking about is not just the evaporation of Lake Superior, but the melting ice caps. Yesterday, the AP reported that Arctic Ice is about to set a record low as well.
Sea ice is particularly low in the East Siberian side of the Arctic and the Beaufort Sea north of Alaska, the center reported
Yep, that's basically the Pacific Ocean side. Anyone who has ever stuck their finger in a glass of ice water knows, by it's very nature, the ice cools the water it melts into. This poses a pretty serious question, are we as a nation capable of dealing with another dust bowl type event?

Whether you believe Al Gore and the vast majority of the scientific community, or the well funded deniers campaign, when it comes to severe climate change we have to be prepared for the consequences. We weren't prepared for Katrina, even though we knew she was coming and thought she would be stronger than she was, and we still haven't recovered.

Lake Superior's previous record low happened four years before the dust bowl. Is that enough of a warning? While the signs are there that we may be heading into another situation like the dust bowl, as a public it doesn't seem like we're talking about preparing for it. We should be, as a nation. There's no excuse not to.

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