flooding.jpgThe British and the Chinese understand global warming has driven their record flooding. The United States? Not so much.

Although you wouldn’t know it from most U.S. media coverage, the record “once-in-a-hundred-year flooding” the Midwest now seems to be getting every decade or so is precisely what scientists have been expecting from the warming.

A 2004 analysis [PDF] by NOAA’s National Climatic Data Center found an increase during the 20th century of “precipitation, temperature, streamflow, heavy and very heavy precipitation and high streamflow in the East.” They found a 14 percent increase in “heavy rain events” of greater than 2 inches in one day, and a 20 percent increase in “very heavy rain events” — best described as deluges — greater than 4 inches in one day. These extreme downpours are precisely what is predicted by global warming scientists and models [PDF].

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In fact, 2007 saw the second most extreme precipitation over the United States in the historical record, according to NCDC’s Climate Extremes Index. Here is a plot of the percentage of this country (times two) with much greater than normal proportion of precipitation derived from extreme 1-day precipitation events (where extreme equals the highest tenth percentile of deluges):
Climate Extremes Index

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Didn’t know that our government kept a Climate Extremes Index? Why would you? The media never writes about it.

The U.S. Climate Extremes Index was explicitly created to take a complicated subject (“multivariate and multidimensional climate changes in the United States”) and make it more easily understood by American citizens and policy makers. As far back as 1995, analysis by the National Climatic Data Center showed that over the course of the 20th century, the United States had suffered a statistically significant increase in a variety of extreme weather events, the very ones you would expect from global warming, such as more — and more intense — precipitation. That analysis concluded the chances were only “5 to 10 percent” that this increase was due to factors other than global warming, such as “natural climate variability.” And since 1995, the climate has gotten much more extreme.

I follow this subject of the connection between climate change and extreme weather very closely — and yet, until 2006, I had not seen a single mention of the Index in the media or even in a scientific paper since its original introduction more than a decade ago. Global warming may be a hot subject, and 2006 was the second most extreme year ever, but just try a Google News search of “Climate Extremes Index” (in quotation marks) — I get no matches at all.

Story after story after story appear in the mainstream media with no link whatsoever between extreme weather and global warming, uncoupled from the man-made trend that will ultimately transform all our lives. The media must do a better job.

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This post was created for ClimateProgress.org, a project of the Center for American Progress Action Fund.