A new report predicts New Jersey — like much of the world — will see a growing number of dangerously hot days by mid-century unless aggressive steps are taken now to decrease heat-trapping emissions.

“The last five years have been the warmest five years on record in the U.S., so it’s only getting warmer,” said Erika Spanger-Siegfried, lead climate analyst for the Union of Concerned Scientists, which today issues "Killer Heat in the United States."

She said the study focused on changes we can expect in the heat index, the National Weather Service’s “feels-like" temperature rating. It combines levels of humidity with actual degrees to produce a “real-feel” temperature.

The analysis found between 1971 and 2000 in New Jersey, there were an average of three days a year where the real-feel temperatures rose above 100 degrees.

But Spanger-Siegfried said if we continue to follow a pattern where no real meaningful action is taken to cut heat-trapping emissions, “this would increase to about 24 days a year by mid-century, and about 50 days a year by century’s end.”

She stressed this means by the end of the century, NJ residents would be exposed to heat indexes about 100 for two months or more each year.

“It causes people to change their plans, how they’re going to spend their day, whether they’re even going to venture outside or stay in the safety of air conditioning," she said.

She said many Garden State residents look forward to the summer because it gives them a chance to enjoy activities outside, but with a growing number of real-feel temperatures rising above 100 degrees “these are the kind of conditions that would force people to stay indoors in the warmer months, in the safety of air conditioning to avoid exposure to dangerous heat.”

To stop this dangerous and dramatic heat increase, she said, we need to begin to decrease “heat-trapping emissions from human activities like powering our electricity system, driving our vehicles, deforestation.”

The union offers an "Extreme Heat and Climate Change" tool to estimate how many days per year any given area might experience by mid-century and late century.

You can contact reporter David Matthau at David.Matthau@townsquaremedia.com

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