River rage: Why Iowa's flood risk is rising

[Strelnikov_]

Des Moines Register
January 2, 2011
http://www.desmoinesregister.com/article/20110102/NEWS/101020341/1001/NEWS/River-rage-Why-Iowa-s-flood-risk-is-rising

Army Corps hydrologists are not convinced that climate change - or anything else - has permanently changed the natural variation in rainfall patterns, said Fournier, the agency's spokesman.

But Gene Takle, an atmospheric scientist at Iowa State University who models climate change, disagrees. While rainfall can vary widely from year to year, the trend in Iowa toward wetter weather is clear, he said.

Not only is the state getting more precipitation than it did just 60 years ago, according to annual rainfall records studied by Takle, it is getting more intense rains. In Cedar Rapids, for example, there's been a five-fold increase in the number of times that more than 1.25 inches of precipitation have fallen eight or more days annually. That's important, because such rains are not absorbed by Iowa soil and result in significant runoff to rivers and streams.

Perhaps more troubling for flood-fighters: Most of the rain is falling in the first six months of the year, when spring floods loom. Takle said ISU researchers believe increased precipitation forecasted to occur by the 2040s could result in 50 percent more flow in the Upper Mississippi River system.

[rurallib]

1. I live in iowa and have seen a drastic change in weather patterns

over the past twenty years.
We used to have rains that would last all day. Now we have downpours that last for a half an hour and dump a couple inches of rain.
We used to have rain through out the year. Now we have tons of rain from April til the middle of June, followed by a couple months of total dry.
Weather patterns have really changed here. I'd like to say it is temporary but it seems to be a set pattern now.