The world is heading to add 57 superhot days a year, but study indicates it could have been worse

The world is on track to add nearly two months of dangerous superhot days each year by the end of the century, with poorer small nations hit far more often than the biggest carbon-polluting countries, a study released Thursday found.

- By SETH BORENSTEIN

But efforts to curb emissions of heat-trapping gases that started 10 years ago with the Paris climate agreement have had a significant effect. Without them Earth would be heading to an additional 114 days a year of those deadly extra hot days, the same study found.

The international collection of climate scientists World Weather Attribution and the US-based Climate Central teamed up to use computer simulations to calculate just how much of a difference the landmark accord has made in terms of one of the biggest climate effects on people: heat waves.

The report — which is not yet peer-reviewed but uses established techniques for climate attribution — calculated how many superhot days the world and more than 200 countries got in 2015, how many Earth gets now and what's projected in two future scenarios.

One scenario is if countries fulfill their promises to curb emissions and by the year 2100 the world warms 2.6 Celsius above preindustrial times. That adds 57 superhot days to what Earth gets now, according to the study. The other scenario is the 4 degrees C of warming that the world had been on track to hit before the Paris agreement. The study found that would double the number of additional hot days.

Pain and suffering coming

“There will be pain and suffering because of climate change,” said Climate Central Vice President for Science Kristina Dahl, a report coauthor. “But if you look at this difference between 4 degrees C of warming and 2.6 degrees C of warming, that reflects the last 10 years and the ambitions that people have put forth. And to me, that’s encouraging.”