Following one of the warmest Augusts on record since 1895, climate scientists are expecting western Massachusetts’ climate to get hotter and wetter over the next century.
The average temperature in August was 74.1 degrees, which is the warmest on record and is 6.5 degrees warmer than the average monthly temperature, according to data published by the National Oceanic and Atmosphere Association (NOAA) on Sept. 9. The previous hottest August was in 2018 at 73.5 degrees. The meteorological summer, from June to August, was the second-hottest on record at 71 degrees.
This warming trend, however, is not a recent development, as the average mean temperature in the Connecticut River Valley has increased by approximately 2.5 degrees since 1895, according to NOAA data compiled by scientists at the University of Massachusetts Amherst.
“We’re experiencing more frequent occurrences of intense heat … and we’re seeing a wetter climate here; annual total precipitation has been increasing,” said Michael Rawlins, the associate director of the Climate System Research Center at UMass. “We’re seeing a reduction in cold, essentially.”
A 2.5-degree difference may feel and seem like nothing to the average person, but Rawlins said it takes an incredible amount of energy to warm up the climate enough to make a difference in a yearly average. Over time, these small temperature changes can have a huge effect on seasons, too.
“Two to 3 degrees doesn’t sound like much of a difference if we’re talking about the temperature of a room over the course of a day,” Rawlins said. “But for the environment, consistently being 2 to 3 degrees above historical averages, there is a great deal of energy change involved.”
As temperatures increase, so does the chance for greater amounts of precipitation to fall throughout the year, according to Ambarish Karmalkar, an assistant professor in the Department of Geosciences at the University of Rhode Island.
“As we warm the atmosphere more and warm our oceans more, that leads to more evaporation from the oceans,” Karmalkar said. “That puts more moisture in the atmosphere and at the same time, as the air gets warmer, it can contain more moisture … if you combine those effects together you can imagine that in a warmer world, you might get more precipitation.”
Rawlins and Karmalkar said winter will be the season when most people will notice change in western Massachusetts.
“If we have higher temperatures in winter, you might get more precipitation that might come down as rain instead of snow,” Karmalkar said. “That has implications for flooding, that has implications for storing water in winter and releasing that in spring.”
And with the average winter temperature hovering around 30 degrees, according to NOAA, Rawlins said any temperature change could significantly affect snowfall and freezing. In the last decade, Rawlins said, winters here have been getting increasingly mild.
“Amherst has seen three winters that have averaged over freezing — think about that for a moment,” he said. “More days that are above freezing in the winter, that has profound implications for our ecosystems and recreation.”
While temperatures around the world are also increasing — the global average temperature change has risen 1 degree since 1895 — New England has, and will continue to see its climate get warmer at a greater rate due to warmer air being pushed in by the Atlantic Ocean, as well as amplified warming that can happen when there is no snow to reflect the sun’s radiation, according to Karmalkar.
Karmalkar said that snow can keep temperatures lower as sunlight is bounced back into the atmosphere, but if the region begins to get less snow due to a warming climate, that heating process begins to compound itself.
“If you have snow on the surface, that might actually keep temperatures lower, but with warming, that snow begins to disappear and as a result, you have a slightly darker surface that absorbs radiation,” Karmalkar said. “Higher latitudes, like us in the northeastern U.S and Canada, face much higher warming in the future compared to other parts of the globe, especially in winter … it’s a positive feedback loop; it amplifies warming.”
While recreational opportunities like skiing will be affected by a lack of snow, warmer temperatures and increased precipitation could upend several industries such as maple syrup production and agriculture as a whole, according to NOAA’s Fourth National Climate Assessment, which was published in 2018.
“Studies suggest that northeast agriculture, with nearly $21 billion in annual commodity sales, will benefit from the changing climate over the next half-century due to greater productivity over a longer growing season,” the report reads. “However, excess moisture is already a leading cause of crop loss in the Northeast. Recent and projected increases in precipitation amount, intensity, and persistence indicate increasing impacts on agricultural operations.”
By 2035, the average temperature could be 3.5 degrees higher than in the preindustrial era, according to the NOAA’s report. By 2070, temperatures across the state could increase by 6 degrees, according to projections created by UMass.
“There are a lot of impacts of warming we can expect to see,” Rawlins said. “More warming in this century, until such a time we start to really seriously mitigate these conditions.”
Chris Larabee can be reached at clarabee@recorder.com or 413-930-4081.
Climate Change at Home is sponsored by Whalen Insurance in Northampton.