2 May 2010

Amazing Flood Event In Tennessee. Climate Related??

Posted by Dan Satterfield

Estimated rainfall from the Nashville NOAA Doppler radar over the past 48 hours. Nashville smashed it's two day rain record with over 13 inches. Click image for full resolution.

Mobile homes floating down I-24 in Tennessee on Saturday. That is something you don’t see every day. It was an amazing and tragic event. Five deaths and many people are homeless and many more have flooded homes and businesses. This was a lot more than a 100 year flood. Nashville weather records go back over 120 years and there has been nothing like this before. (Update: Chris Darden of the NWS once worked in Nashville and tells me the records go back to 1871!)

I am usually the first to cringe when I see extreme weather events blamed on climate change. You cannot blame ANY single weather event on climate change. That does not mean it did not play a role however.

Weather is what you get and climate is what you expect.

Estimates of Ocean heat content. Click for full sized image. From EPA

The temperatures have warmed about 1 degree C over the past century and to assume that this will not have an affect on our day to day weather would be a claim that is not easy to back up scientifically.

That increase in temperature means the air can hold about 7% more water vapor. That means you can expect more rain. It’s basic physics and it has been understood for much longer than weather records have been kept in Nashville.

Last week the EPA released a very well done report on climate change impacts in the U.S. There are a couple of graphics that caught my eye. They are especially interesting since there are still so many people who believe the myth that the planet is getting cooler.

If anyone tells you this they are either lying to you or ignorant of the basic science.

The heat energy stored in the Oceans is really the planet’s thermometer. We named our planet EARTH.

The planets real thermometer. Something to remember next time someone tries to tell you the planet is not warming up.

Aliens would name it OCEAN.

The oceans control everything on our planet.  Most of all the weather.

So was the flooding in Nashville climate related? Would it have occurred if the air was not holding more water vapor?


Did climate change exacerbate it?


One of the core predictions of the future warmer world is more extreme rainfall events. There are some studies that show 100 year floods happening every 40 or 50 years. Even more frequently than that in many areas.

Just some things for thought on a rainy dark night in Alabama….