Harsh winter weather is making its way across the United States, with bitterly cold air in the northeast and blizzards on the east coast next week.

Forecasts assume that Chicago can expect several inches of snow. Six to eight inches of snow could fall Monday and Tuesday along the I-95 corridor from Washington to New York to Boston.

“Winter has finally shown up here in the northeast,” said Greg Carbin, director of forecast operations for the National Weather Service’s Weather Forecast Center.

Disruptions to the upper atmosphere phenomenon known as the polar vortex can send icy explosions from the Arctic to mid-latitudes, deterring Europe, Asia, and parts of North America. The disruption and its effects have lasted an unusually long time this year, said Jennifer Francis, a senior scientist at Woodwell Climate Research Center, with two polar vortex disruptions this year and possibly a third on the way.

Research into the interplay of the complex factors causing explosions from the polar vortex is ongoing, but climate change appears to be part of the mix. While warming means milder winters overall, “the motto for snowstorms in the age of climate change could be: go big or go home!” Said Judah Cohen, director of seasonal forecasting at Atmospheric and Environmental Research, a customer information company provides information about weather and climate-related risks.

The United States has seen heavy snowfall in the Sierra Nevada and Great Plains for the past week. Earlier this month, Madrid was buried under a crippling foot and a half of snow, and parts of Siberia suffered an unusually long cold spell, with temperatures below 40 degrees Fahrenheit – and one area recorded temperatures nearly 73 degrees below. (Record heat was seen in some areas last summer.)

The wild weather has its origin in the warming Arctic. The region is warming faster than the rest of the planet, and research suggests that the rising temperatures weaken the jet stream that surrounds the pole and generally holds it in that cold air. In early January, a wave of sudden warming hit the polar stratosphere, the zone five to thirty miles above the surface of the planet.

When one of these “sudden stratospheric warming” occurs, it strikes the polar vortex, shifting arctic air and moving through the atmosphere to people who suddenly have to pile up their blades and break out.

Amy Butler, a scientist at the NOAA Chemical Sciences Laboratory, offered an analogy: “Imagine a bowl of swirling water or a cup of coffee that you just stirred. If you suddenly put a spoon in the water and block the swirling flow at the very top, it will slow down or disrupt the water below. “

While the scientific evidence for climate change is undisputed, the link between climate change and the disturbances in the stratosphere is not as clear. Dr. Cohen was the author of an article in Nature Climate Change last year that looked at winter data from 2008 to 2018. The team has seen a sharp increase in winter storms in the northeast over the past decade. “Severe winter weather is much more common when the Arctic is at its warmest,” said Dr. Cohen.

Dr. However, Butler said that throughout the historical record, dating back to 1958, “there is no evidence of a long-term trend” in polar vortex perturbations. The weather patterns affecting the eddy occur “naturally, even without climate change,” with some decades uninterrupted and other decades almost every year.

For Dr. Francis, a senior scientist at Woodwell Climate Research Center, the influence of climate change on these phenomena is inevitable, if somewhat mysterious. “We are changing the planet in such dramatic and irreversible ways,” she said. “The atmosphere is different now. The earth’s surface is different now. The oceans are different now. So there must be some connections that have yet to be discovered when we do more research on the stratospheric polar vortex. “

However, what will happen in the next few days, especially in the northeast, is becoming clear, although it is difficult to predict exactly where exactly the snow will fall and how deep it will be.

“Still, the cold comes,” said Dr. Cohen, “and someone gets snow.”