Scorching summer days to sizzle more by 2100: study | Reuters

"The extremes warm faster than the averages," said Rob van Dorland, a spokesman for the Royal Netherlands Meteorological Institute which wrote the study with scientists at Utrecht University.
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Dorland said it was unclear why extreme temperatures would rise so fast -- a theory was that warmer soils dry out, reducing the amount of heat they can absorb from the sun. "If the soil is drier, then solar energy goes more to heating the air," he said.