Monday, August 22, 2011

Some Discoveries of the International Great Lakes Study

Communities across the Great Lakes shorelines are meeting to discuss falling water levels as part of a new International Upper Great Lakes Study. Apparently there's some public commentary thing going on.

I've been watching this group from afar for a while: The International Upper Great Lakes Study.

I admit, though, that I haven't done a great job of following exactly, precisely what they've been doing, and I admit I have only skimmed their reports.

For example, I know that their original goal was to see if and to what degree the St. Claire River was responsible for lower water levels in the Upper Great Lakes. For those not in the know, the St. Claire River is between Lake Huron and Lake Erie. Lake Huron flows into Lake Erie via the St. Claire River.

Years ago there was some concern that a widening St. Claire River was draining the upper Great Lakes faster, so a group got together to find out.

The answer..."sort of"

From the 1980s the St. Claire River water outflow from Huron to Erie increased by 5.8%.

The group didn't recommend any type of remedies.

Now the group wants to study two things: possible remedies AND the OTHER causes of dropping water levels in the upper Great Lakes. One such cause is climate change and a resulting reduction to tributary contributions to the upper Great Lakes. Another cause of falling water levels: something called "isostatic rebound". Apparently, that's when earth that was compacted by glaciers slowly, slowly springs back up, like wet moss after you step on it. isostatic rebound would creation the ILLUSION of falling water levels, since it's actually the land that's RISING. Crazy stuff.

Of course, all this begs the question, are the water levels in the upper Great Lakes falling? I guess the answer is: Yes. What's the big deal? Well...lots of things, from vanishing wetlands to barges having to carry less cargo due to a lower draft.

Anyway...stand by.

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