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Study Claims Searing Heat Waves In The Future

23.02.2016 17:58 Age: 2 yrs

Today's once in 20-year heat waves could become annual occurrences across more than half of the world's land areas by 2075, claims a new study. It also concluded that heat waves with a 1-in-20 chance of occurring during a future year will be much more extreme than heat waves with the same probability today

Click to enlarge. For large portions of the world's land surface, future heat waves with a 1-in-20 chance of occurring in any given year are projected to become more extreme than heat waves with the same chance of occurring today. Stringent efforts to mitigate human-produced carbon emissions would reduce the amount of land area at risk for these intense heat waves—defined as three days of exceptionally hot temperature. Courtesy: NCAR


by Laura Snider, National Center for Atmospheric Research

Sweltering heat waves that typically strike once every 20 years could become yearly events across 60 percent of Earth's land surface by 2075, if human-produced greenhouse gas emissions continue unchecked. 

If stringent emissions-reduction measures are put in place, however, these extreme heat events could be reduced significantly. Even so, 18 percent of global land areas would still be subjected yearly to these intense heat waves, defined as three exceptionally hot days in a row.

These are among the findings of a new study by Claudia Tebaldi of the National Center for Atmospheric Research and Michael Wehner of the Lawrence Berkeley National Laboratory. The study, funded by the U.S. Department of Energy and published in the journal Climatic Change, quantifies the benefits society would reap, in terms of avoiding extreme heat events, if action is taken now to mitigate climate change.

"The study shows that aggressive cuts in greenhouse gas emissions will translate into sizable benefits, starting in the middle of the century, for both the number and intensity of extreme heat events," Tebaldi said. "Even though heat waves are on the rise, we still have time to avoid a large portion of the impacts."

More frequent, more severe

A tool for cost-benefit analysis



Benefits of mitigation for future heat extremes under RCP4.5 compared to RCP8.5 by Claudia Tebaldi and Michael F. Wehner published in Climatic Change, doi:10.​1007/​s10584-016-1605-5

Read the abstract and get the paper here.


NCAR/UCAR news release here.