As climate change raises sea levels, intensifies weather patterns and prolongs heat waves across the planet, it will also create complex challenges for mountainous regions — and for those who recreate in them.
The global average temperature has increased about 1 degree Celsius since the Industrial Revolution. But some locations — including high elevations — are warming even faster, said McKenzie Skiles, an assistant professor in the University of Utah’s geography department. The effects are seldom straightforward, but the bottom line is that the world’s snow cover is shrinking.
At the recent Wyoming Snow and Avalanche Workshop, before an audience of backcountry snow sports enthusiasts, Skiles presented the best prognosis science can offer for long-term climate trends in Earth’s high mountains.
“This is not projected to stop any time soon,” she said. “Even if we totally shut off the emissions of greenhouse gases, the mountain snowpack would continue to change.”
It’s far from obvious exactly what that change will entail, especially in any given environment. Rather than simple and indiscriminate warming, the essence of climate change is variability.
For example, in many cases snowfall may even increase at higher elevations, because a warmer atmosphere can hold more moisture (Skiles said the process may have played a role in last winter’s historic avalanches across the West).
At lower elevations, though, where the air is warmer, precipitation is more likely to fall as rain. At all elevations, snow is closer to melting temperature from the moment it falls, and therefore prone to recede earlier each year. Snow cover isn’t changing much in, say, March, but Skiles said the decrease is evident later in the spring and early summer.
That melt is coming earlier, she said, at an average of five days each decade. She said that rate will likely accelerate as the global temperature rises.
Skiles drew much of her presentation from a recent report she contributed to, in which researchers with the Intergovernmental Panel on Climate Change outlined the effect of climate change on mountainous regions, and other parts of the cryosphere (essentially, places where water is frozen).
The decrease in snowpack seems to be taking a toll on the ski industry, according to the report, though mostly at low-elevation resorts, like those in eastern states. Some strategies that resorts have used to combat these changes, like snowmaking, are expected to become less effective.
Such climatic changes will come with ups and downs for skiers, snowboarders and snowmobilers. Less snow obviously means less accessible terrain, but Skiles noted that it could also mean fewer and smaller avalanches over time (though likely more wet avalanches).
Hoesung Lee, chair of the IPCC, explained in a news release that the consequences of climate change in these parts of the world aren’t limited to those who live and play in them.
“The open sea, the Arctic, the Antarctic and the high mountains may seem far away to many people,” he said. “But we depend on them and are influenced by them directly and indirectly in many ways — for weather and climate, for food and water, for energy, trade, transport, recreation and tourism, for health and wellbeing, for culture and identity.”
Skiles emphasized that “we’re not just going to lose snow instantly … Ultimately what’s going to happen in our lifetimes is just more variability.”
But taken as a whole, evidence from the Himalayas to the Andes to the Rockies shows that alpine areas are warming, and that’s a strong indicator that snow cover will keep retreating throughout the 21st century.
“If we look at stations all over the world,” Skiles said, “the story is the same.”