Jan 7, 2018

Global warming may be driving the East Coast chill

The cold snap has nearly frozen over the American side of Niagra falls. Photo: Geoff Robins / AFP via Getty Images

This weekend could be the coldest on record for several areas across the Northeast, brought on by what several scientists say is a weakening polar vortex. Meanwhile, the rest of the world is currently experiencing warmer-than-average temperatures, including both the North and South poles. The connection between these seemingly contradictory weather patterns may be climate change.

The bottom line: The consensus among researchers is that the Arctic is warming faster than any other region in the world. The resulting loss of sea ice in the area could be weakening the polar vortex, allowing cold air from the North Pole to be misplaced over lower latitudes, like North America, and thus creating these cold snaps. But the extent of that link is debated.

The breakdown: Super cold air is usually trapped in the Arctic by the polar vortex, a massive circular weather pattern around the North Pole. Judah Cohen, Director of Seasonal Forecasting at Atmospheric and Environmental Research, described the polar vortex as acting like a dam that locks the frigid air up north. But Cohen says Arctic warming weakens the polar vortex — and bursts that dam. "Warm air then rushes up to the pole, and the cold previously located over the Arctic escapes ... to lower latitudes where it's not normally residing."

The debate: While there is increasing evidence Arctic warming and colder winters are related, "less consensus has been achieved so far about the mechanisms underlying the linkages between Arctic climate changes and atmospheric circulation changes over North America," said Doerthe Handorf, a climate researcher with the Alfred Wegener Institute.

Weather is a complex system driven by a lot of other factors — including ocean currents and atmospheric processes. Improved models and data have only recently uncovered direct links between some major weather anomalies and climate change. But the science is still new. "Existing knowledge gaps and controversy ... among the scientific community" have to be settled to understand the complex relationship between the polar vortex and climate change.

Why it matters: "These extreme [weather] events and their links to conspicuous climate change (such as the Arctic meltdown) are helping the public to understand that climate change is not a problem for the future. It's happening right now to all of us," said Jennifer Francis, Research Professor at Rutgers University's Institute of Marine and Coastal Sciences.

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Trump threatens to "assume control" of Minneapolis over unrest

Flames from a nearby fire illuminate protesters standing on a barricade in front of the Third Police Precinct in Minneapolis on Thursday. Photo: Kerem Yucel/AFP via Getty Images

President Trump threatened via Twitter early Friday to send the national guard to Minneapolis following three days of massive demonstrations and unrest in the city over George Floyd, a black man who died in police custody this week.

Details: "I can’t stand back & watch this happen to a great American City, Minneapolis. A total lack of leadership. Either the very weak Radical Left Mayor, Jacob Frey, get his act together and bring the City under control, or I will send in the National Guard & get the job done right," Trump tweeted after a police station was torched by some protesters. "These THUGS are dishonoring the memory of George Floyd, and I won't let that happen. Just spoke to Governor Tim Walz and told him that the Military is with him all the way. Any difficulty and we will assume control but, when the looting starts, the shooting starts. Thank you!"

Editor's note: This is a developing news story. Please check back for updates.

Updated 47 mins ago - Politics & Policy

In photos: Protests over George Floyd's death grip Minneapolis

Protesters cheer as the Third Police Precinct burns behind them on in Minneapolis on Thursday night. Photo: Stephen Maturen/Getty Images

Cheering protesters set a Minneapolis police station on fire Thursday night in the third night of unrest following the death of George Floyd, a black man who died in police custody in the city, per AP.

The state of play: Minnesota's governor on Thursday activated the state's national guard following violent outbreaks throughout the week, as the nation waits to see if the officers involved will be charged with murder.

Updated 6 hours ago - Health

World coronavirus updates

Data: The Center for Systems Science and Engineering at Johns Hopkins; Map: Axios Visuals

New Zealand has a single novel coronavirus case after reporting a week of no new infections, the Ministry of Health confirmed on Friday local time.

By the numbers: Nearly 6 million people have tested positive for COVID-19 and over 2.3 million have recovered from the virus. Over 357,000 people have died globally. The U.S. has reported the most cases in the world with over 1.6 million.