Wilfred Wollheim, an associate professor in the Department of Natural Resources and the Environment at UNH and a senior author of the study , published recently in the journal Ecology and Society, said he and his team linked climate scenarios with models of forest and aquatic ecosystems to make their predictions.

If carbon dioxide emissions continue at the same rate, by the middle of the 21st century, we could see fewer snowy winter days, hotter summers, and a drastic decline in the number of fish currently found in cold-water streams, the university said in a statement Thursday.

Researchers at the University of New Hampshire say major effects of climate change could be felt sooner than we think in New England — by mid-century.


“We made sure that the model was performing reasonably well before we predicted what’s going to change in the future,” he said.

When they applied their model to the area around the Merrimack River in New Hampshire, they found a number of environmental conditions will worsen because of climate change.

The number of hot days with temperatures of 90 degrees or more could rise to 70 per summer. Chances of flooding could increase. Fish used to living in cold water could die off not only because the water is warming, but also because water in coastal areas is taking in more nitrogen, which pollutes the water.

The biggest effect, however, will be in urban areas where people live, the university said, because land use and population growth interact with climate change to affect the environment. One effect of climate change could be a problem with supplying them with sufficient water, he said.

Wollheim said in order to prevent these predictions from coming true, we must act fast.

“If we don’t do anything about the greenhouse gas emissions, the effects will be even worse” in coming centuries, he said.


He suggested implementing policies that reduce greenhouse gas emissions, such as the Paris climate accord, as well as reducing land use and investing in storm and wastewater infrastructure.

“Even though we see evidence currently of climate change, it’s only going to get worse if we continue to emit greenhouse gases at the rate we’re going,” he said. “We ran a scenario where greenhouse gas emissions were limited early on, and in that scenario, we could keep the effects low.”



Alyssa Meyers can be reached at alyssa.meyers@globe.com. Follow her on Twitter @ameyers_.