Tuesday, May 10, 2011

One Hundred Year Flood

The Mississippi River crested today at the highest level since the Great Flood of 1937. Swollen by melting snow in northern regions and heavy spring rains, North America’s largest river rose to within a foot of its all-time record. I took today’s photo from atop Chisca Mound in Memphis, Tennessee, a city built on high ground known as the fourth Chickasaw Bluff. Trunks of massive trees drift in the fast-moving current. The tops of tall cottonwood trees can be seen one mile away, marking the river’s west bank and the Arkansas Delta. Seven miles, straight ahead, beyond the river’s main earthen levee, sits the city of West Memphis, Arkansas; fifteen miles ahead is Peace Bee Farm. This year’s flooding along the Mississippi River has had an effect upon both managed and natural honey bee colonies. The Memphis Area Beekeepers Association lost several hives when its bee yard was flooded by waist-deep waters of the Wolf River, a tributary of the Mississippi. Swarms that I captured this week near the Mississippi River in Arkansas may have been driven from natural nests in the cavities of trees by rising waters. Some of the honey bee colonies clearly perished, but many of the resilient bees seem to have escaped flooded trees and floating hives.

Humans, like honey bees, are social beings. We accomplish more as a community than could be possible as individuals. Designing and building a levee system to protect from powerful forces like a once in a hundred year flood requires the combined efforts of many. Viewing the Mississippi River above flood stage is humbling. Another thing comes to mind: All of this water draining from 31 states was carried by clouds and deposited as rain or snow. As the climate warms, one of the effects will be increases in mighty floods. Native Americans, like the Chisca, moved into the rich river bottom lands to hunt and farm, and then retreated to high ground when the Mississippi floods each spring.

1 comment:

  1. It's actually a cooling event in the Pacific, La Nina, that has caused so much snow and rain to fall this year. Last year was one of the strongest El Nino events recorded in the Pacific, and although we didn't set a record here in North America, the scientists have recorded it as the warmest Average Global Temperature year on record, since they've been able to calculate such things. Having it immediately followed by what may be the strongest recorded La Nina event (Pacific cooling), while not unprecedented, is a bit surprising. The affect of a cold Pacific is that it allows the "Arctic Vortex", as they call it (cold air swirling around the North Pole), to send out cold tentacles of air that swirl down over us. They have kind of a counter clockwise motion as they fold back on themselves sometimes. That rotation is distinctive when you look at satellite cloud pictures on the evening weather. If you follow the jetstream, you can usually see the full depth of the Arctic Vortex tentacles. I saw a decent post on it over at melisseus.com http://www.melisseus.com/2011/04/science-la-nina-weather.html