NH CHAT - June 2025
NHPR’s By Degrees Climate Summit: Healthy Connections
In early May, a handful of NH Healthy Climate staff and members attended NHPR’s third annual By Degrees Climate Summit, thanks to a generous donation from Bob Dewey and Pam Van Arsdale.
Our organization and mission was well-represented during the event’s panel discussion, which featured members of our Board of Directors and Advisory Board Kaitlynn Liset and Semra Aytur as panelists.
Watch their wide-ranging discussion on climate change in New Hampshire below.
We were proud to sponsor By Degrees Climate Summit, and we were grateful to be a part of these community conversations. Outside of the engaging speaker portion of the summit, we hosted a table where we made connections with community partners and met 18 new supporters who signed-up for our email list.
For more By Degrees Climate Summit content, watch the fantastic keynote address from Dr. Jola Ajibade.
Pollen Levels and Climate Change: A Growing Public Health Concern
For anyone living with seasonal allergies, asthma, or chronic lung or heart disease, pollen season can pose serious health risks. Symptoms may range from mild, such as itchy eyes, to severe, including asthma attacks that require hospitalization. Unfortunately, these problems are becoming more common, as studies show that pollen levels are rising globally. One study, which analyzed data from over 800 sites across North America, found a 21% increase in pollen levels since 1990(1).
Scientists widely agree that human-caused climate change is the primary driver of this increase. Greenhouse gases like carbon dioxide (CO2) and methane, produced mainly by burning fossil fuels, have warmed the planet by approximately 1.4°C. In New Hampshire, for example, the growing season—the time between the last frost in spring and the first frost in fall—has lengthened by 35 days since 1980. A longer growing season allows plants more time to grow larger and release more pollen.
In addition to warmer temperatures, rising CO2 levels directly effect plant growth. As many of us may remember from middle school biology, CO2 is essential for photosynthesis. More CO2 means faster and larger plant growth—and more pollen. Before the industrial era, atmospheric CO2 levels were around 220 parts per billion (ppb). By 1950, they had risen to 310 ppb, and today they exceed 430 ppb—a dramatic increase driven by fossil fuel consumption.
Numerous studies have shown that plants grown in high-CO2 environments release significantly more pollen(2). A 2021 study published in The Journal Nature warned that, if current trends continue, pollen levels could increase by up to 200% by the year 2100(3).
While many people think of pollen as a seasonal nuisance—covering our cars and sidewalks in green dust—it represents a serious health hazard for a large portion of the population. And without action, this problem is only going to get worse. Reducing atmospheric CO2 will require a coordinated global export to move away from fossil fuels.
The challenge is clear—and the time to act is now.
Bob Dewey, MD
(1) PNAS Feb. 2021
(2) International Journal of Biometerology May 2018
(3) Nature Communications March 2022
Please Sign Our Petition to Defend our National Climate Assessment
We, the members and supporters of NH Healthy Climate, are deeply concerned with the Trump Administration’s dismantling of the Congressional mandate for a periodic National Climate Assessment. By first cancelling the contract for technical support and staffing (April 8), and subsequently dismissing the hundreds of volunteer scientists and experts who work to compile this critical bi-decade report (April 28), the Administration is not only disobeying the will of Congress (Global Change Research Act of 1990), the Administration is threatening our national security, safety, and public health.
Can we count on your continued support?
As Summer temperatures rise, pollen lingers, and heavy rain persists, our mission to increase public awareness of climate change’s human health impacts only becomes more important.
We rely on donors like you to sustain critical programs, like the CHICKs program which aims to protect our youngest generations of Granite Staters’ physical and emotional health in the face of a warming climate. You can help sustain CHICKs and all of our Climate and Health programs by donating today.
Joan Widmer
Treasurer, Board of Directors
‘Zombie moose’: As climate change shortens winters, ticks ravage New Hampshire’s moose population
Every fall, winter ticks in New England sit on shrubs or other plants waiting for a large animal to pass by so they can latch on and begin sucking out blood. This has a huge impact on the area’s moose, wildlife biologists say.
“They basically become zombies and die,” Eric Orff, a New Hampshire-based wildlife biologist, said. “We have zombie moose.”
According to estimates from New Hampshire Fish and Game, the Granite State’s moose population peaked in the late 1990s at around 7,000 to 8,000 moose. It has since declined to roughly 3,000 to 4,000.
Most tick species move from host to host frequently, but winter ticks find a moose, deer, or other animal around November and extract their blood for the entirety of winter. And it’s not just one or a couple ticks on each host. Rather, hundreds or thousands of ticks often latch onto a host. This is a process called questing and it has a huge effect on moose, particularly calves.
“April is the month of death for calves,” Orff, who works as a field biologist at the National Wildlife Federation and serves as vice president of the New Hampshire Wildlife Federation, said. “The adult ticks are feeding one more time before they fall off and they basically drain the moose’s supply of blood.”
Around April, the female ticks fall off their hosts to lay their eggs. If they land on snow as opposed to dry land, the eggs are less fruitful. However, as climate change represses winter weather, tick populations have boomed.
“Over the last 20 years, instead of one winter out of six or eight or 10 being truncated, now, a majority of them are,” Orff said. “So what has been found in more recent moose studies, including those done in New Hampshire and in Maine and Vermont the last two decades, is that it really significantly impacts the moose calves born that previous spring.”
While adult moose are better able to fend off the tick infestations, he said, 70% of calves don’t make it to 1 year old. And this also affects adult female moose. Orff, who has been studying moose and other wildlife for decades, said that when he and his colleagues began this research in the 1980s, nearly all older female moose gave birth to two calves. Now, he said, less than half the females even become pregnant. He said this is a result of being underweight from the ticks, but also because climate change is making summers warmer, which results in them eating less. Underweight moose are less likely to give birth.
“It’s really a double whammy,” he said.
A third factor, he said, is that south of the White Mountains brain worms have proliferated. While moose populations have plummeted, white-tail deer populations have nearly tripled from about 40,000 in the early 1980s to around 100,000 to 120,000 in the southern half of the state due to milder winters, he said. Brain worms are common in deer, and while those brain worms don’t harm the deer, they can be fatal to moose.
Orff noted the economic costs of lower moose populations. He said people used to travel to the North Country specifically to see the moose.
“Moose viewing in New Hampshire for a period of years was a $10-million-a-year industry,” he said. “I don’t know if there’s any companies that still do it. I think there are. But you used to be able to go out and, in a night, see a dozen or a half dozen moose at least. Now they may go several hours and see no moose.”
These die-offs also cause ecological issues. Henry Jones, moose project leader for Fish and Game, said moose carcasses serve as a food source for scavengers, which are seeing rising numbers in the wake of this population collapse. Jones said the past two years have been particularly severe for tick infestations.
To address this, the state is issuing more hunting permits. Jones said tick populations rise when the moose population has high density. By killing off moose, the survivors fare better, he said. The state is also working with the University of New Hampshire to study the conditions in which ticks proliferate best. Jones said this is all about “keeping them from getting really high density and causing this kind of cyclic relationship of lots of tick mortality.”
However, the hunting strategy still results in dead moose and low populations. Orff noted the conundrum.
“I guess that’s the debate,” Orff said. “Is it better to have far fewer moose and less sickly moose? … Baby moose who drop dead from no blood in April or taking some of them out that will be utilized by hunters eating them?”
Jones said the state is acting based on the wishes of citizens.
“We did a public survey to understand what the residents want with the moose population in 2024,” Jones said. “People want there to be the same or more moose, but they don’t want there to be more moose if they’re unhealthy.”
Still, Orff said none of these are a true solution to the overall problem. Moose will continue dying, he said, until we put an end to humans’ warming of the planet.
William Skipworth
New Hampshire Bulletin
