Did human activities cause the Mississippi River flood?

May 10, 2011

As the Mississippi River crested at near-record levels near Memphis, Tennessee, a nagging question surfaced at a Capitol Hill briefing: are people to blame? According to one expert on water and hydrology, the answer is closer to yes than no.

“I’m not suggesting these (floods) are caused by climate change, but there’s very clear scientific evidence that the risk of flooding on the Mississippi River is increasing because of human influence,” said Peter Gleick, president of the California-based Pacific Institute.

Human influence comes in at least two ways, Gleick told a briefing that drew congressional staff and personnel from U.S. agencies including the National Oceanic and Atmospheric Administration. (You can see the briefing slides here.) First, the carbon dioxide emitted by the burning of fossil fuels — cars, factories, power plants — loads the atmosphere with climate-warming greenhouse gas, pushing global mean temperatures higher.

Climate scientists have projected that this will make wet areas wetter and dry ones dryer, and this appears to be happening in the continental United States. In some parts of the Mississippi River basin, there has been as much as 20 inches (50 cm) of rain in the last 30 days, which is up to 600 percent of the normal amount, Gleick said.

Projections indicate there will be less winter snowpack — which locks water away until the spring melt — and more rain, which drains quickly into rivers like the Mississippi.

People also build levees that channel the river, packing it into a narrower, deeper space when waters rise, and they put houses, farms and factories behind the levees, putting themselves in the path of any potential flood, Gleick said.

Projections can be wrong, of course. Take the projections of flood severity along the Mississippi. When the “Father of Waters” swelled disastrously in 1993, it was called a 500-year flood — a rise in water expected only twice in a millennium. Then came the flood of 2008, the second 500-year flood in two decades. This frequency of severe floods has prompted the U.S. Army Corps of Engineers to re-evaluate their statistics on Mississippi River flooding, according to Gleick.

“Flood frequency along Mississippi River is not a constant,” he said. “That flood risk is growing.”

Photo credits: REUTERS/ERIC THAYER (A man takes a picture of a flooded mobile home park as floodwaters slowly rise in Memphis, Tennessee May 8, 2011)

REUTERS/John Sommers II (The Belle of Louisville steamboat at the Louisville River Front after being inundated by flood waters from the Ohio River in Kentucky, April 29, 2011)

4 comments

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Posted by Docrandyl | Report as abusive

I don’t think this flood just came out of nowhere – there was definitely a human influence behind it. I just hope that larger companies make the best of it; Immediate Response Group and other centrally located companies specialize in disaster response and asset recovery.

Posted by Joe6210 | Report as abusive

What a HOOT! This flood will break a 1927 record. And was that 1927 flood caused by man made global warming? Over thousands of years Louisiana was created as an alluvial delta for the Mississippi River. Every 100 years or so the main channel changed. Man comes along and decides to restrict the river to provide for his desires. Mom nature says… “Hey, you guys are fussing with the wrong river in the wrong spot.” Of course this flood is the result of man’s interference. Man’s interference with trying to control the river channel. Reminds me of the folks that build the million dollar beach front home in hurricane alley then cry Global Warming when the inevitable happens. Common sense is what was washed away when man built New Orleans 6 feet below sea level. “Those who ignore the flood lessons of history and doomed to repeat them”… Ma Nature, 2011

Posted by Bogsucker | Report as abusive

[...] Did human activities cause the Mississippi River flood? [...]

[...]  I’m judging; deal with it.)  What caused the flooding? A variety of factors including human activity and the Mississippi’s quest to change her course.  Amid the reports of preventative [...]

The 1927 flood was man made. It was an attempt by some New Orleans bankers to grab land. There is some anecdotal and documented evidence that suggest the levee was destroyed by work crews. None the less the destruction they caused was far greater than they had expected.

The fertile crescent(Mesopotamia) was the richest farm land the planet has seen in 10,000 years. Yet Sumerian and Babylonian societies set it firmly on the path to desertification over 4000 years ago. The need for firewood and lumber in Africa and South America has expanded the Sahara and created new deserts in Brazil. Looking at the Midwest of the U.S. by Satellite(Google Earth) will show just how much the Dakotas, Nebraska and Kansas are already desert. Water tiles for irrigation drainage has exacerbated flooding as well as inundate the Mississippi river systems with fertilizer that has spawned giant algae blooms in the Gulf of Mexico. These blooms prevent oxygen from entering the waters thus preventing marine life from living under them. Interestingly, the menhaden who feed on algae are a threatened species as most of them have been over fished for industrial fertilizer.

Mountain top removal for extracting coal and failed fly ash containment has devastated the Appalachian mountain region destroying whole towns and fresh water. The introduction by man of alien marine and land species has altered the environment around the world adversely affecting fishing and agriculture. Fresh water is also a resource that is in decline around the world.

No one talks about the ecological disasters caused by decaying WWII nuclear production facilities in Georgia, Tennessee and Washington State. These sites are impossible to clean up and are monitored by the federal government(NRC and EPA). It is simply not credible to believe the Congress is not aware. Still many of our elected representatives claim nuclear fission generated electricity is safe and necessary. Remember the nuclear reactors in Japan were designed by General Electric and these same designs are in use here in the States.

Perhaps if our government wasn’t in the business of lying to the People about such conditions(to protect corporate interests/re-election campaign donors), there would be overwhelming public consensus to move in a different direction regarding power generation. Clearly the activities of man have been changing the face of our planet in epic fashion.

Posted by coyotle | Report as abusive

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