Wild weather in a warming world
Rough winter weather is working its way across the United States, with bitterly cold air hitting the Northeast and snowstorms expected along the East Coast next week.
Forecasts predict Chicago can expect several inches of snow. And 6 to 8 inches of snow could fall along the I-95 corridor from Washington through New York and up to Boston on Monday and Tuesday.
“Finally, winter’s made an appearance here in the Northeast,” said Greg Carbin, chief of forecast operations for the National Weather Service’s weather prediction center.
Disturbances to the upper-atmosphere phenomena known as the polar vortex can send icy blasts from the Arctic into the middle latitudes, chilling Europe, Asia and parts of North America. The disturbance and its effects have persisted for an unusually long time this year, said Jennifer Francis, a senior scientist at the Woodwell Climate Research Center, with two disruptions of the polar vortex this year and potentially a third on the way.
Research into the interplay of the complex factors that bring on blasts 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 era of climate change could be ‘Go big or go home,’” said Judah Cohen, director of seasonal forecasting at Atmospheric and Environmental Research, a company that provides information to clients about weather and climaterelated risk.
The United States has already seen heavy snowfall in the Sierra Nevada and in the Great Plains in the last week. Earlier this month, Madrid was buried under a paralyzing foot and a half of snow, and parts of Siberia suffered an unusually lengthy cold spell with temperatures of 40 degrees below zero Fahrenheit — and one area recorded a temperature of nearly 73 below. (Last summer, some of the same areas experienced record heat.)
The wild weather has its origins in the warming Arctic. The region is warming faster than the rest of the planet, and research suggests the rising temperatures are weakening the jet stream, which encircles the pole and generally holds in that frigid air. In early January, a surge of sudden warming hit the polar stratosphere, the zone 5 to 30 miles above the surface of the planet.
When one of those “sudden stratospheric warmings” happens, it delivers a punch to the polar vortex that can cause the Arctic air to shift and make its way down through the atmosphere to people who suddenly need to layer up and break out their shovels.
Amy Butler, a research scientist at the NOAA Chemical Sciences Laboratory, offered an analogy: “Picture a bowl of swirling water or a mug of coffee you’ve just stirred. If you suddenly put a spoon in the water and block the swirling flow just at the top, it will start to slow or disturb the water underneath it.”
While the scientific evidence supporting climate change is indisputable, the connection between climate change and the disruptions in the stratosphere is not so settled.