Conservation and Biodiversity

North American winters are losing snow and ice

As we recently reported, climate change is coming for autumn, making falls shorter and less colorful. Unfortunately, a new report warns that autumn isn’t the only season at risk. In North America, dreams of a winter wonderland are also under threat.

Over the last century, northern U.S. and eastern Canada have been losing cold, snowy and icy conditions over the winter, according to a study published in the journal Ecological Applications. And a frost-free winter can hurt everything from tourism to ecosystems to human health.

Though we typically look at climate change through the lens of longer summers, shorter autumns and earlier springs, we often overlook the big impacts a warming world has on winter, said Alexandra Contosta, lead author of the study.

“Some of the biggest changes that we may see, especially in our parts of the world, with regards to climate, may actually be during the winter,” Contosta, a research assistant professor at the University of New Hampshire, told Earth Day Network.

For the study, Contosta and her team analyzed 100 years of weather data across northeastern North America, roughly from Minnesota to north of Maine. What they found doesn’t bode well for what we consider a traditional North American winter.

In general, the researchers saw a decrease in frost, ice and extreme cold days and an increase in thaw days. Milder temperatures may feel welcomed — for example, less money spent on heating bills and less time shoveling show — but snow and ice directly influences ecosystems and the communities that rely on them.

“I think people, especially the average public, rarely stop to think about how important the cold temperature and snow are,” Contosta said.

As snow cover and ice decrease, insect pests increase. The southern pine beetle is one of the “most aggressive tree-killing insects in the world,” said the study, and when frigid winters aren’t around to kill them, these beetles can spread and attack forests. With less snow cover and ice, mammals and birds may also be forced to adapt, causing migrations and throwing off food chains.

For residents of this region, less snow and ice can cause more problems. Though hypothermia and other cold-related diseases may decrease, ticks, mosquitoes and other pests can increase, which put people at risk to more vector-borne diseases, like Lyme disease and West Nile virus.

What’s more, local economies can expect to take a hit from less snowy winters. New England states and Canadian provinces have built economies around snowy, icy winters — in the U.S. and Canada, winter sports are hundred-million-dollar industries. Less snow-covered days, however, may put these businesses in jeopardy.

Climate change drives these warmer, wetter winters. And as the world continues to warm, we don’t just have different ecosystems and less money from tourism or recreation, Costosta said. We’ll have a totally new landscape, both across the globe and in local communities.

“I really hope that [this study] helps people understand how climate change is happening in their own backyard,” said Contosta. “[These changes] affect everything, from public health to our culture and history, and to the wildlife that we love.”

To slow human-caused climate change, we need to curb greenhouse gas emissions and pressure leaders to take bold action. April 22, 2020 is the 50th anniversary of Earth Day. Now is the time to mobilize for collective action on climate change. Join the movement.