The report does say scientists are "virtually certain" — 99 percent — that the world will have more extreme spells of heat and fewer of cold. Heat waves could peak as much as 5 degrees hotter by mid-century and even 9 degrees hotter by the end of the century.
Weather Underground meteorology director Jeff Masters, who wasn't involved in the study, said in the United States from June to August this year, blistering heat set 2,703 daily high temperature records, compared with only 300 cold records during that period, making it the hottest summer in the U.S. since the Dust Bowl of 1936.
By the end of the century, the intense, single-day, heavy rainstorms that now typically happen only once every 20 years are likely to happen about twice a decade, the report says.
The report said hurricanes and other tropical cyclones — like 2005's Katrina — are likely to get stronger in wind speed, but won't increase in number and may actually decrease. Massachusetts Institute of Technology meteorology professor Kerry Emanuel, who studies climate's effects on hurricanes, disagrees and believes more of these intense storms will occur.
And global warming isn't the sole villain in future climate disasters, the climate report says. An even bigger problem will be the number of people — especially the poor — who live in harm's way.
University of Victoria climate scientist Andrew Weaver, who wasn't among the authors, said the report was written to be "so bland" that it may not matter to world leaders.
But Masters said the basics of the report seem to be proven true by what's happening every day. "In the U.S., this has been the weirdest weather year we've had for my 30 years, hands down. Certainly this October snowstorm fits in with it."
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