The report, which has taken 100 scientists two years to produce, provides some of the starkest evidence yet that extreme weather is linked to global warming, with experts saying it was "very likely" man-made emissions had led to an increase in daily maximum temperatures.
Scientists judged there was a 90-100% probability that the entire world will see hotter, longer and more frequent heat waves, reported the Guardian.
Heavy rains are also likely also become more common, they predict, while droughts may intensify in vulnerable areas such as southern Europe, central North America, Central America, and southern Africa.
In the US, hurricanes are likely to become stronger, though scientists are unsure whether they would be more frequent.
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The report does not conclusively state that man-made emissions increase extreme weather, however, which the Guardian says is due to "the difficulty of the difficulty in tying specific extreme weather events to human-induced global warming":
As such events occur naturally, there will always be a variability in where and how frequently they occur, and scientists must attempt to cancel out that "noise" in detecting an underlying trend.
The effects of the new extreme weather are set to hit developing countries particularly hard, according to USA Today's map of the panel's forecast. Pacific islands will be subject to coastal erosion and flooding as sea levels rise, while West Africa will face severe droughts and East Africa heavy flooding.
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As well as the loss of lives and habitats, economic losses from weather disasters are increasing everywhere, the IPCC said.
2011 is already a record year for billion-dollar disasters in the US, the Washington Post reported, citing National Climatic Data Center figures that show there have been at least 10 such disasters this year, including Hurricane Irene on the East Coast, flooding on the Mississippi, and tornadoes in the Midwest. They are aimed to have cost the US economy $50 billion in total.