Donald Wuebbles, a professor of atmospheric sciences at the University of Illinois at Urbana-Champaign, is going to do the thing the IPCC wishes people would not do; attribute local weather events to climate change.

The hurricanes and droughts like we had in 2012 will be more frequent in future U.S. five-day forecasts, as will other extreme weather events, and it's because of human-driven climate change he argues today at the AAAS meeting in Boston. In the 1950s, the number of days that set record high temperatures was equal to the number of days that set record low temperatures. By the 2000s, the United States was twice as likely to see a record high as a record low.

While the IPCC would prefer that the media not attribute such things to climate change - after all, the situation in the 1930s was worse than today - the AAAS meeting is a safe audience. In his 2009 keynote speech at the AAAS meeting, former Vice-President used a projection of sea level rises that was far more aggressive than climate science estimates but few objected. It turned out to have been drawn from insurance company estimates rather than science, and he withdrew that slide after an outcry from outside the meeting noted it was not evidence-based.

"Human-driven climate change is in fact driving changes in severe weather, and that leads to a lot of potential impacts in both humans and wildlife that end up being costly in many different ways," Wuebbles said in his statement about the talk.

As global climate changes, weather patterns are altered. This is because the increasingly warmer atmosphere holds larger amounts of water vapor, which energizes storms, Wuebbles said. Weather-related disasters incur huge expenses, taxing both public funds and private equity. He cites National Oceanic and Atmospheric Administration claims that 11 extreme weather events cost more than $1 billion each occurred in 2012. And the US Midwest, which had been immune to warming until 2012, finally had a drought.

"What we've seen in general is that the number of billion-dollar events has increased over the last three decades," Wuebbles said. "It's not just hurricanes, it's really a number of different types of weather extremes that are increasing, and that's what the worry is."

In his talk, Wuebbles will discuss the current understanding of severe weather in relation to the science of climate change, as well as speak about the issues and uncertainties that will affect the U.S. and world in the coming years.