Extreme Snowstorms Still Occur in a Warming World: Climate Change's Impact on Snow

You'd think that a warming world would cause milder winters. But that isn't the case, according to new research. Scientists have found that even though average snowfall will decrease, extreme snowfall events will likely still occur in the Northern Hemisphere.

"Many studies have looked at average snowfall over a season in climate models, but there's less known about these very heavy snowfalls," said Paul O'Gorman, one of the researchers, in a news release. "In some regions, it is possible for average snowfall to decrease, but the snowfall extremes actually intensify."

In order to better understand these events, the researchers studied daily snowfall across the Northern Hemisphere using 20 different climate models. Each of these projected climate change over a 100-year period, given certain levels of greenhouse gas emissions. In addition, they examined both average seasonal snowfall and extreme snowfall events under current climate conditions, and also under projected future warming.

So what did they find? Under relatively high warming scenarios, low-elevation regions with winter temperatures initially just before freezing experienced a 65 percent reduction in average winter snowfall. Yet in these same areas, heavy snowstorms became only 8 percent less intense. More surprisingly, in higher-latitude regions, these snowstorms became even more intense and deposited 10 percent more snow.

"You might expect with a warmer climate there should be major changes in snowfall in general," said O'Gorman. "But that seems to be true to a greater extent for average snowfall than for the intensities of the heaviest snowfall events."

The findings reveal a bit more about what might happen with snowfall as our climate warms. More specifically, it shows that we'll continue to have snowfall, despite the warming weather.

"We often hear people claim that a big snowstorm is evidence that the climate is not warming, but these results make it clear that such storms do not provide much evidence about a changing climate," said Anthony Broccoli, professor of environmental sciences at Rutgers University, who did not contribute to the study.

The findings are published in the journal Nature.