From the Center for American Progress Action Fund via Maggies Farm:

This tragic, deadly, and destructive weather -- not to mention the droughts in Georgia, California, Kansas, North Carolina, Florida, Tennessee, North Dakota, and elsewhere across the country -- are consistent with the changes scientists predicted would come with global warming. Gov. Chet Culver (D-IA) called the three weeks of storms that gave rise to the floods in his state "historic in proportion," saying "very few people could anticipate or prepare for that type of event." Culver is, unfortunately, wrong. As far back as 1995, analysis by the National Climatic Data Center showed that the United States "had suffered a statistically significant increase in a variety of extreme weather events." In 2007, the U.N. Intergovernmental Panel on Climate Change (IPCC) concluded that it is "very likely" that man-made global warming will bring an "increase in frequency of hot extremes, heat waves and heavy precipitation." The Nobel Prize-winning panel of thousands of scientists and government officials also found, "Altered frequencies and intensities of extreme weather, together with sea level rise, are expected to have mostly adverse effects on natural and human systems." In 2002, scientists said that "increased precipitation, an expected outcome of climate change, may cause losses of US corn production to double over the next 30 years -- additional damage that could cost agriculture $3 billion per year." Scientists have also found that the "West will see devastating droughts as global warming reduces the amount of mountain snow and causes the snow that does fall to melt earlier in the year."

Beyond the fact that these folks could profitably learn about a writing concept called a "paragraph break,"  this analysis is hilariously bad.  The key fact not mentioned is that the first five months of 2008 have been the coldest in decades, both in the US and worldwide, and have been far colder than 2007, which saw much milder weather and fewer tornadoes this time of year (more here).  In fact one could easily, but probably incorrectly since it is such a short period of time, posit that warming would reduce tornadoes, since this year's cold weather has increased them so much.

Because we have not seen any global warming trend over the last 10 years, alarmists have switched to "climate change" as their bogeyman.  In particular, they argue that global warming will increase severe weather frequency.  There is a lot of evidence that this statement is incorrect, but lets accept it for a minute.  Their theory still requires an intermediate step of warming.  There is no mechanism anyone has ever described where increasing CO2 directly yields increases in severe weather without passing through warming first. 

But this is exactly what they are trying to claim, at least with the masses:  They are in effect claiming that somehow CO2 causes severe weather directly.  But this is simply impossible.  If the world has been colder this year, then severe weather, if it results from temperature change at all, is resulting from the cold weather, not warming.

In fact, the article goes on to imply that crop problems this year are due to man-made effects, that somehow global warming is causing these failures.  But crop problems this year are almost entirely due to cold spring tempertures and late frosts.  You have really got to be a master PR spinner to convert frost and cold issues into a global warming problem.

The whole thing is pretty funny.   More on tornadoes and warming here.

Update:  I could post a zillion of these, but here is one example of what is ailing crops:

Wheat, durum and barley crops are currently one to two weeks behind normal due to cold weather so far this spring, with temperatures 3° to 5°C below normal.

"A continuation of cool weather could lead to delayed development and increased risk of frost damage this fall," said Bruce Burnett, the CWB's director of weather and market analysis, in the board's release Thursday.

Update #2:  US Tornado fatalities graphed for the last 100 years:

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