Not all of the wetland drying up in Michigan is drought related. Michigan used to be covered with up to a mile of ice during the Pleistocene glaciation period. When the ice melted a lot of weight was removed and the entire lower peninsula has since then been rebounding at a rate of approximately 1/8" per year, which is quite a lot in geologic terms. The hinge line is along the Michigan-Ohio border; everything north of that is slowly rising, with the rate of rise increasing as you go north. I'm told there is a now a lot of land between the road and the water near Mackinaw bridge. At some point there may be no need for the bridge. There are numerous old sandy beach lines visible in the black organic potato fields in the thumb that used to be beach 'cliffs' but have now rotated enough to form ridges. Some of the wetlands are simply being elevated above the water tables that have kept them wet. There is nothing that can be done about this, of course; it's just the planet at work. Some of the drying is also a result of simple eutrophication caused by the decay of organic matter into soil or muck, as it were, that slowly fills in wetlands and kettle lakes left behind by the glaciers. This is an annual cycle as vegetation grows and dies with the seasons. Some of this could also be a result of the lowering of water table levels resulting from the removal of water for agriculture and domestic and industrial use, as in the Central Valley in California, where it has interestingly enough resulted in the lowering of the landscape by 20ft or more. Don't even get me started on the sad situation in New Orleans, where they will at some time in the future need dikes 200ft high to keep the city, which will be in a giant trench, dry; it's a lost cause caused by channelization of the river system to enhance shipping that has caused the sediments that would normally be deposited in the naturally sinking delta to continue on into the Gulf. They can't win that one. Get used to it as these processes will continue for some time to come.
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