Saturday, September 10, 2011

Muddy Waters

The flight from Connecticut to the DC area yesterday was thoroughly uneventful – the best kind! The adverse weather that came north with the remnants of Tropical Storm Lee had moved on leaving no trace aloft. But it's another matter at zero feet AGL.

Here (left) a look at the Hudson River from 8,000 feet, a few miles north of the Tappan Zee Bridge. Normally the entire river is the color of the waters seen at the lower left of the image, in Croton Bay. The bay is protected by the Croton Point peninsula. Outside this embayment, the river is a rich, silty brown from the massive upstream runoff that the rains of the past week generated. Upstate New York experienced almost as much flooding as Vermont and many small rural streams turned into raging torrents. Now, the Hudson is carrying the effluent to the sea.

About an hour later, this was the view of the Susquehanna from 6,000 feet. The stream flows from the bottom of the image toward the top and is usually a steely blue-gray. But with the upper Susquehanna reaching flood-stage and beyond at Binghamton and Wilkes-Barre, it isn't surprising to see it turned brown by a burden of silt headed for the Chesapeake. It may be a while before the region's rivers recover their accustomed colorations. Meanwhile, it's enlightening to see the changes induced by Mother Nature from the perspecive of a small aircraft a mile or so up.

And what happens to all that silt? Look at this NASA Landsat 5 image from 2 September. It shows (from a somewhat higher perspective) the Connecticut River depositing silt generated by runoff from Hurricane Irene into Long Island Sound. (Click here for a full description of the image.) That used to be a large part of Vermont, right there.

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