Washington, Oregon, California and British Columbia are in the midst of a brutal heat wave that has broken records with 115-degree temperatures and widespread highs above 100 degrees.
It seems unthinkable to imagine Vermont, land of snow and frigid winters, experiencing such a once-in-a-lifetime event. But data and interviews with experts suggest that while Vermont may not become Oregon anytime soon, it is vulnerable to extreme heat waves — and it may not be ready for them.
The National Weather Service defines a heat wave as three consecutive days of temperatures 90 degrees and higher. But state climatologist Lesley-Ann Dupigny-Giroux said research from one of her team members suggests that Vermont’s standard should be 87 degrees or higher.
“Ninety degrees is fine [as a threshold] for some parts of the country and the nation,” she said. “Because of Vermont’s location, because of our population not being as acclimated to these really, really high temperatures, 87 is a better threshold for us.”
It’s unclear whether Vermont is experiencing more 87-and-higher days because of climate change. While the number of hot days has increased since 2000, Vermont experienced a long period of heat and drought in the 1940s that makes our heat look milder by comparison.
What is clear is that Vermont is just as susceptible to the forces that caused extreme heat out West. There, a high pressure system trapped hot, dry air closer to the ground.
“If you don’t have a lot of moisture, then whatever moisture is there, it’s going to lessen even more, and then those heat conditions just tend to self-perpetuate,” Dupigny-Giroux said.
That interaction happens in Vermont, too: In April, drought conditions combined with hotter-than-normal temperatures to drive heat up even further, creating what seemed like freakishly hot days.
“Dry conditions, high temperatures, low humidities [and] heat waves kind of go together, because it's that sort of positive feedback loop that’s going on,” she said.
Those conditions can occur in summertime in Vermont, too. She gave the example of 1999, when the state had two nearly back-to-back heat waves in July and another heat wave in early September.
“You couldn’t hike for too long, because the temperatures were so high, right? And then it was so dry, it was also dangerous to be outside,” Dupigny-Giroux said.
She called the West’s heat wave a “teachable moment” for Vermont, bringing focus to the possibility of extreme heat in typical cold, wet regions.
Preparing Vermont for heat
The situation out West is also a reminder of the need for Vermont to prepare to protect its most vulnerable populations, Dupigny-Giroux said, and for the state to use a systematic approach that captures everyone.
“How are we doing this so that we’re not forgetting some people, we’re not forgetting some health impacts or health conditions? How are we doing this, that we’re not forgetting parts of the state? How are we doing it so that we’re not forgetting to reach everybody?” she said.
People who are less mobile, people with disabilities, and older people are particularly susceptible to heat illnesses, like heat exhaustion or heat stroke, according to the Vermont Department of Health.
That risk is even higher for low-income people in that demographic because they may not have cooling systems, or be able to afford cooling their home, VDH said.
Data from the Department of Public Service suggests very few Vermonters have extensive cooling systems. A 2015 study of new construction found that only a third of new homes had installed air conditioning, and an additional 13% had room air conditioners (like window units).
A smaller study by DPS from the same year also found very few multi-family residences had room air conditioners. Most newly constructed apartments had central air conditioning, but the majority of older apartments did not.
Official cooling centers throughout the state are housed in municipal shelters that typically open during emergencies, or when there are multiple-day stretches of bad weather, like high heat.
Erica Bornemann, director of Vermont Emergency Management, said the state requires each town to create an emergency management plan, usually updated on Town Meeting Day, that lists the location of shelters and whether they provide services like warming and cooling.
When a heat wave hits the state, emergency management directors at the town and state level will begin reaching out to the public, encouraging people to take precautions and advertising cooling center locations.
A page on the state’s website, titled, “municipal cooling locations,” hosts a link to a list of public libraries in Vermont and says staff will update the page as they become aware of other open cooling centers.
“We don't usually use it unless we're actually pointing people to the page or to the site to find locations,” Bornemann said.
When hot weather lasts only one or two days, Bornemann said the agency suggests people go “to libraries that have air conditioning or going to take a walk through a mall that has air conditioning, and just generally, locations that are open and available to the public.”
Those looking to cool off can also call 2-1-1 for information about shelters, cooling centers and transportation options.
When shelters are open, Bornemann said Vermonter’s aren’t always flocking to them.
“That’s the other challenge, especially in Vermont and New England — people don't like to go to shelters,” she said. “So we’ll open them and they won’t come.”
Vermonters are good at getting ready for cold snaps, she said, and people can benefit from thinking about heat in a similar way.
“Frankly, the most important piece here is individual preparedness,” she said, adding that planning is particularly important for people who are most vulnerable to the impacts of heat.
“We can negate the impacts of extreme heat and go a long way if we just check on our neighbors,” she said.
How to cool your home
Richard Faesy, co-founder of Energy Futures Group in Hinesberg, said Vermont’s rank as having the oldest housing stock in the nation posed a challenge for protecting homes — both from hot and cold weather.
“We have a lot of weatherization work to do on those homes to reduce our winter energy usage, and a lot of the same applies for the summers, as well,” he said.
That includes insulating homes to help them maintain a steady and constant temperature year-round, he said. In the summer, preventing sunlight coming in from West-facing windows is important as well.
One promising new technology can help with both hot and cold weather: Heat pumps, increasingly installed as a heating method in Vermont, can be reversed to remove heat from your house in summer, Faesy said.
Efficiency Vermont and local utilities offer incentives to make heat pumps cheaper, although they’re still “not cheap,” at about $4,000-5,000, he said.
“It’s two to three times as efficient [to cool] your house with heat pumps, as with a window air conditioner,” he said. “And they also have much higher capacity — instead of doing a full room, they could do a floor of a house.”
Hot water
Prolonged heat also affects Vermont’s natural environment, and Oliver Pierson, who manages the state’s lakes and program, said water temperatures in Lake Champlain have increased over time, particularly in the shallow sections of the lake.
“We’re projecting now that Lake Champlain will freeze over, from only once every four years right now, to, perhaps by 2050, freezing over only once a decade,” he said.
Pierson said heat causes a number of impacts on lakes, including reducing the amount of oxygen in the water, and changing the way it handles nutrients. Higher temperatures also create optimal conditions for harmful algae blooms.
All of these factors impact the lake’s ecosystem, and create “additional risks for both water quality and freshwater species living in a lake,” he said.
Pierson said it’s possible with planning to mitigate some of the harmful effects of heat on aquatic ecosystems. It will be important to reduce the amount of nutrients flowing into water bodies, he said. Planting trees and shrubs that provide shade can keep temperatures low along shorelines.
On a broader scale, he said, the best way to affect the escalating water temperatures is to address climate change.
“How do we reduce contributions of heat-trapping greenhouse gases to the atmosphere?” he said. “That’s something that we think about as well.”
Correction: Heat pumps can be reversed to remove heat from your house in summer. An earlier version of this story used an incorrect word to describe the process.
