Sunburned woman wearing a droopy sunhat

The future of summer

Action needed to prevent nearly a month of 100+ degree weather in region 

July 29, 2019

Michael Rawlins and Ambarish Karmalkargeosciences, were quoted in a recent article in the Daily Hampshire Gazettegiving further context to a Union of Concerned Scientists’ report about future summers in our region. 


From “Killer heat could plague region if climate change left unchecked”: 

There might be more sweltering days in the not-too-distant future if no or little action is taken to cut greenhouse gas emissions and curb climate change, according to a report published by the Union of Concerned Scientists (UCS) titled “Killer Heat in the United States.” 

The report predicts how frequently temperatures will go above 90, 100 and 105 degrees Fahrenheit on the heat index — a National Weather Service measurement that combines temperature and relative humidity to estimate how hot it feels outside. 

The report calculates these statistics for every county in the country under several scenarios: no action is taken to cut emissions this century; some action is taken and greenhouse gas emissions decline midcentury; and swift action is taken to keep the average global temperature increase to 2 degrees Celsius or below, the same level the Paris Agreement set as a goal. 

As a baseline for comparison, researchers calculated the average number of extreme heat days between 1971 and 2000. Over that period of time, Hampshire County has had, on average, no days annually where the heat index topped 100 degrees Fahrenheit, according to the report. Without declines in greenhouse gas emissions, the county will have a predicted 10 days each year with the heat index topping 100 degrees by the middle of the century. 

“What we’ll experience this week, the hottest day, we’re expected to get that possibly 27 days each year by the end of the century,” said Michael Rawlins, associate director of the Climate System Research Center at the University of Massachusetts Amherst, echoing the findings of the report. 

Between 1971 and 2000, Hampshire County also had an annual average of no days with a heat index above 105, a level the National Weather Service says is likely to cause sunstroke, heatstroke or exhaustion with prolonged exposure. If current trends continue, the report predicts there will be 15 of those days each year on average late this century, but if greenhouse gases are seriously curbed, there will be only one. 

“Clearly, if we take no action, climate model projections indicate a substantial increase in the number of dangerously hot days throughout this century,” Ambarish Karmalkar, a UMass research assistant professor at the Northeast Climate Adaptation Science Center and Department of Geosciences, wrote in an email to the Gazette. “But there are clear benefits if we do act.”  

The report says that some groups will be more affected than others, including those who work outdoors, like on farms or construction sites, and low-income people, as they often have less access to air conditioning or transportation to a cooler space. 



Share this story: