It’s late Friday night, 11/29/24, and snow is moving into the Great Lakes region. Hot off the press from AccuWeather.com at 10:48 pm Central is this:
“Dangerous, life-threatening conditions will develop in the snow belts downwind of the Great Lakes into early next week as lake-effect ramps up with white-outs, rapid accumulation and plunging temperatures.”
This is a familiar prediction for the Great Lakes region. Snowfall is the stuff of legends in Buffalo, NY, which sits on the eastern edge of Lake Erie. With global warming intensifying, can residents of Buffalo hope that someday soon the sky won’t be as cold and their snowstorms won’t be as devastating?
Not according to results of a recent multi-institutional study on future climate conditions and lake-effect snowstorms. It was led by Michigan Technological University climate scientist Miraj Kayastha.
A lake-effect snowstorm (LES) is created when frigid, dry air passes over a warm lake. Dry air has a huge capacity to absorb water. When the temperature differential between cold air and warm water causes lake water to evaporate, the moisture exchange between the lake surface and forming clouds destabilizes the atmosphere. Rough, higher ground surrounding the lake can also surrender water particles, adding to the moisture exchange and atmospheric instability. Ultimately, newly fattened clouds dump immense amounts of snow into a tempestuous sky.
In Kayastha’s study of the future of lake-effect storms, he and colleagues took what they call a “storyline” approach, using two modeling systems to examine and quantify the forces that created a single LES storm in November of 2022. That storm dropped 77 inches of snow onto Erie County, New York. (That’s Buffalo’s county.) With that information and using their modeling tools, the scientists projected how strongly those November 2022 forces might be at play in the Great Lakes region during the middle and late 21st century, when the climate is expected to be warmer (and then warmer still). In the 2022 storm, snowfall accounted for 89% of the total precipitation. The rest was rain. Kayastha and his team projected that, in the anticipated mid-century climate, snowfall from LES storms will make up about 78% of the precipitation. By the end of the century, almost half (54%) of the precipitation from LES storms will be rain.
Unfortunately, a relative increase in rain is not necessarily good news. Rain on snowpack presents a significant risk of flooding. What’s more, as the century progresses and both air and water warm and evaporation-blocking ice melts, there may be more precipitation altogether. Kayastha’s team predicted that, by the end of the 21st century, total LES storm precipitation will be enhanced by as much 14%.
AccuWeather.com’s forecast for the Great Lakes area this week is concerning. If history tells anything about the future, the predicted storm may be more of the terrible same-old same-old. Just under two years ago (December of 2022) dozens of people in Eerie County died in a LES storm. Atmospheric instability created by evaporation and precipitation contributed to windspeeds of 70 mph. Windchills fell to -30F and helped create the calamity.
At the time this article went online, Kayastha was not available for comment and the storm was closing in. The Great Lakes are the world’s largest unfrozen surface freshwater system. Lake-effect storms don’t happen every year, but they’re a common occurrence. Climate change doesn’t seem likely to bring relief.
