Science Source

Trends in Weather Extremes

The author's trend analysis shows that almost everywhere heat extremes (defined as the highest daily average temperature of the year) are now warmer than a century ago, following the obvious first-order connection with global average temperature
- One exception is in the eastern U.S. where heat extremes are now roughly as warm as they were during the Dust Bowl of the 1930s
Finds that cold events (the daily average temperature of the coldest day of the year) heat up even faster than the heat extremes, up to a factor of five times the global mean temperature
Looks at the highest daily precipitation of the year as a measure of extreme precipitation and finds that the highest daily mean of the year has increased at more stations than it has decreased
Finds that the average global increase in precipitation is similar to the increase of the amount of water the atmosphere can hold at higher temperatures (the Clausius–Clapeyron relation), about 7% per degree Celsius, but local trends are often different from the global average
Finds that even if the theoretically expected increase in the most intense tropical cyclones is not yet detectable, their physical impacts have increased substantially already
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