Late-September heat wave leaves climate experts stunned
"Never been a heat wave of this duration and magnitude this late in the season," reports NOAA
27 September, 2017
Century-old records across the Midwest and East Coast are being shattered by a monster late-September heat wave — the kind of extreme weather we can expect to get much worse thanks to President Donald Trump’s policies to undermine domestic and global climate action.
From Wednesday through Tuesday, for example, Chicago sweltered through “the only occurrence on record of 7+ consecutive 90°[F] days entirely within September.” Every day of the heatwave was 92°F or above, and every one set a new record high for that date.
“It’s perhaps obvious that global warming means more frequent and intense heat waves,” climatologist Michael Mann noted in an email to ThinkProgress. “But what is less obvious is how climate change may be impacting the behavior of the jet stream in way that causes more persistent weather extremes, giving us even more extreme and longer-duration heat waves than we would otherwise expect.”
“Many of the worst heat waves in recent history, including the 2003 European heat wave and the 2011 Texas/Oklahoma heat wave, were associated with this effect,” Mann said.
The latest science makes it very clear that stronger heat waves are becoming far more likely, thanks to global warming — and that the warmer it gets the worse the heat waves will get.
Indeed, the new Nature Scientific Reports study finds that for each additional 1.8°F of global warming during the summer, there would likely be:
- 15 to 28 more heat wave days each year
- Heat waves would last 3 to 18 days longer
- The peak intensity of heatwaves will increase 2.2°F to 3.4°F
But while the rest of the world is working to limit additional warming as much as possible, Trump’s policies would take us to upwards of 5.4°F or more additional warming. In the worst case, we can see as many as 80 more heat wave days, heat waves could be 50 days longer, and the peak intensity could be as much as 10°F higher than it is now.