HANOVER — With heavy rains punctuated by heat waves, the Upper Valley is already seeing the impacts that the International Panel on Climate Change projects for the region. The expansive report that the UN panel published on Monday describes accelerating global warming and devastating extreme weather, and it definitively ties climate change to human activity.
The report stressed the effects of differences in warming above pre-industrial levels — 1.5 degrees Celsius as opposed to 2 degrees Celsius — would mean to life on Earth. The IPCC reports that the world is on track to reach 1.5 degrees of warming over pre-industrial levels by the 2030s, but that there is still time to avoid the larger increase.
While the difference of a half-degree may seem insignificant, Justin Mankin, a Dartmouth geography professor, said “that average of a half a degree really belies some of the risks that get baked into it.”
“A 2-degree world is considerably worse than a 1-degree world,” Mankin said. “That half-degree could mean a several-degree change in the hottest day of the year, for example, or a 10% to 20% increase in the heaviest downpour that occurs in the Green Mountains.”
The IPCC projects that the northeastern U.S. will see a marked uptick in heavy rain events and heat waves. Mankin said the “drastic oscillations between wet and dry” that the region has seen in the last few years are consistent with predicted impacts of climate change.
Jonathan Winter, a geography professor at Dartmouth, studies extreme rain events. He said that warming surface temperatures on the Atlantic Ocean give storms more energy to tropical storms. Warmer air can hold more moisture, effectively increasing the size of the “bucket” that pours out rain in a heavy storm.
“Since 1996, we’ve been getting, in an average year, about 50% more extreme precipitation than previous to that — so 1901 to 1995,” he said.
“The more greenhouse gases go up, the worse off we are, the worse those floods and the worse those heat waves get,” Winter added, “and anything that we can do to reduce the amount of greenhouse gases, that takes down the amount of heat waves and flooding.”
The changing climate will force the region’s economy to adapt, not least because the New England winter is already changing fast.
“What has really stood out in New Hampshire is the high rate of change during our winter season particularly. That’s been driving the majority of our warming,” said Mary Stampone, the Granite State’s climatologist.
She went on to detail a range of ways the state is already seeing the impact of a changing climate: Thanksgiving ski weekends will likely become confined to history, and wildlife is moving farther north and to higher ground. Peaches are growing well in orchards that were once too cold, and invasive species — once kept at bay by long winters — are gaining against native species in forests.
Mankin explained that “very small changes in temperature can drastically alter the fraction of precipitation that falls as snow versus as rain.”
The outdoor activities and ski resorts that attract tourists to the region will have to adapt to unpredictable winter conditions and, likely, less snow. With more rain likely to fall on frozen soil, Mankin also warned that winter flooding may also become more common as runoff hits land and has nowhere to drain.
Policy solutions The 234 scientists who authored the report conclude that people can still determine just how bad climate change will get, and local residents are already pushing their states to take more aggressive action.
“Any kind of excuse for hand-wringing around policy action, like, ‘Oh let’s wait for better scientific information’ — that argument couldn’t hold much water before, and now it holds absolutely no water,” Mankin said. “There’s no justification, from a science perspective, for inaction. All the uncertainty as to how bad climate change is going to be is dominated by us.”
The IPCC warns that even if the current pledges made under the Paris Agreement were met and supplemented with “very challenging increases in the scale and ambition of mitigation after 2030,” global warming would still surpass the 1.5-degree threshold. According to the IPCC’s models, aggressive action including a “high price on emissions” and a significant shift in investment patterns, as well as “rapid and far-reaching transitions in energy, land, urban and infrastructure (including transport and buildings), and industrial systems.”
“We’re talking about a total reconfiguration of the global economy and the energy on which it relies. It is a necessary, a possible path, but there are some massive (challenges) for the labor and technology transfer, all those things,” Mankin said.
In both Vermont and New Hampshire, residents are advocating for more aggressive policies to limit carbon emissions.
John Gage, a former computer scientist, volunteers his time to lead New Hampshire’s chapter of the Citizens’ Climate Lobby. The group, which includes 108 residents of the Upper Valley, advocates for the Carbon Fee and Dividend, a bill that would establish a price on carbon that would put dividends in the pockets of families.
From his perspective, New Hampshire is falling behind on climate policy.
“Other states are incentivizing solar deployments and doing things like net-metering to help deploy renewable energy by individuals and by businesses and by municipalities. That’s helping lower their carbon footprint,” he said.
He argues that there will be a price on carbon by 2030, and that “states with a lower footprint will be naturally more competitive than states like New Hampshire that have been delaying this.”
350Vermont, a nonprofit, advocates for an aggressive response to climate change in its namesake state.
“For everybody who’s paying attention, the IPCC report is not a surprise, but it’s downright scary,” said Andrea Stander, who serves on the organization’s board. “This hopefully lights a fire under some of the people who have been dragging their feet or not taking this seriously.”
In Vermont, the Legislature passed the Global Warming Solutions Act over Gov. Phil Scott’s veto in 2020. Now, a state climate council is developing a plan that it will present to the Legislature after a period for public comment.
Stander said 350Vermont is advocating speedy action that prioritizes the people on the front lines of climate change in the state — whether that’s laborers working in hotter weather, the elderly living in apartments without air conditioning or farmers struggling with heavy rains.
“Vermont is in a really good position to show the way,” said Stander, who envisions Vermont as a potential model for other states and even countries.
“This IPCC report has underlined — we need (to act) fast,” she said. “And that’s probably going to mean a bigger level of investment and a real eye towards what we need to get out of that investment.”
Claire Potter is a Report for America corps member. She can be reached at cpotter@vnews.com or 603-727- 3242.