If you want to know how cold and snowy winter is here in most parts of the United States, look no further than remote Siberia, “the refrigerator of the Northern Hemisphere,” says meteorologist Judah Cohen.
In fact, the amount of October snow cover across that vast Russian province thousands of miles away is key to the winter forecasts Cohen makes for the United States each year through Atmospheric and Environmental Research, a subsidiary of Verisk Analytics.
He said the forecasts are used by private clients from the insurance and energy sectors. But readers of the free blog are more diverse, including people from sectors such as agriculture, emergency management, wildlife management, public works, snowplow operators, the media, and many others.
According to Cohen, the snow that falls this month in Siberia will help determine the severity of our winter weather, especially in the central and eastern United States. Forecasts including Siberian snow were correct 75% of the time over more than two years, Cohen says. Contracts.
Here's why Cohen's predictions are linked and when data for this winter will be available:
How will Siberian snow affect our weather?
Snow reflects about 70% to 80% of the Sun's warmth back into space, while bare Earth reflects only 20%. October is the time when Siberia and the entire Eurasian region experiences the greatest expansion of snow cover, sometimes increasing by as much as six million square miles, which is larger than the total land area of the United States, including Alaska.
How Siberia is covered in snow in the fall helps Cohen formulate his forecast because the icy cold air over the region will slowly flow into Europe and eventually North America by midwinter. Essentially, more snow in Siberia equates to colder air and the possibility of more snow than usual in the United States
What is the polar vortex?:An in-depth look at how this will affect winter weather in the United States.
The cycle also affects broad weather patterns, with more snow cover often causing the infamous polar vortex to drop unspeakably cold air into the eastern United States, or temperatures dropping even lower in a single cold snap.
It also tends to turn the Arctic Oscillation climate pattern “negative,” another sign of a colder winter in the East.
Cohen's research on these complex interactions continues to evolve. Recently, he's been researching what happens when the polar vortex becomes elongated, stretching like a rubber band. “When PV extends, the likelihood of severe winter weather in the United States increases dramatically,” he said.
Not the expectations of the Western United States
Siberian snow doesn't typically affect winter forecasts in the West, because the cold air that helps flow in from the Arctic tends to get blocked by the region's mountains, and doesn't play a role in precipitation there either.
Cohen, whose research is funded by the National Science Foundation, said he discovered the relationship between snow cover in Siberia and weather in the United States by chance. As a postdoctoral fellow, he conducted global climate modeling experiments to determine the impact of unusual snow cover in North America on other large-scale climate patterns.
Instead, he found the strong relationship that now forms the basis of his predictions, which he says have been 75% accurate since he started including Siberian snow cover as a factor in winter forecasts in 1999.
Last winter, he correctly predicted the mild winter most of the eastern United States would experience. “The only area we may have missed is the cooler temperatures in the southwestern United States,” he told USA TODAY.
Cohen's winter weather forecast will be posted on his blog in the last week of November.
