Sub-zero windchills, heavy snow, and ice storms have paralysed most of the country over the Christmas weekend. As President Biden urged people to take the arctic blast seriously and follow local weather warnings, experts warned that the winter storm could put animals and ecosystems at risk.

A “once in a generation” winter storm has paralysed large parts of the US over the Christmas weekend, bringing strong winds, heavy snow, and below-freezing temperatures across at least 45 states. 

The “bomb cyclone” – as forecasters dubbed it – caused extremely rapid and dramatic declines in temperatures across several states. In less than a day, temperatures in Wyoming dropped 70 degrees and reached -70F (-57C) in eastern parts of the state, the lowest seen so far during this historic arctic blast. Texas went from 41F (5C) to -1F (-18C) in just six hours and in the same time span, Missouri also recorded a 30-degree drop. 

Speaking from the White House on Thursday, US President Joe Biden warned everyone planning to travel for Christmas to do so immediately. “It’s dangerous and threatening,” he said. “It’s really very serious weather. And it goes from Oklahoma all the way to Wyoming and Maine, so I encourage everyone to please heed local warnings.”

At least 50 people have died of weather-related incidents and hypothermia so far, Sky News reported. Airlines cancelled more than 6,000 flights from Wednesday throughout Friday and nearly 7,000 more were cancelled over the weekend, according to the tracking website FlightAware. On Christmas Eve, more than 1.8 million homes and businesses had no electricity. As of Monday night, about 60,000 people were still without power, as data from the tracking site Poweroutage.us showed.

“We haven’t seen this in a long time,” said climate scientist Daniel Swain, explaining that such sudden temperature drops can cause a “shock to the system, whether that’s human bodies or power grid.”

But experts have also warned of the dramatic impact that the arctic blast can have on animals, plants and ecosystems, even those that are typically able to cope with cold temperatures. Migratory birds including the chipping sparrow, Carolina wren, American robin and northern cardinal, who typically move north to escape the milder winters brought on by global warming in recent years, may find themselves unable to cope with the extreme chill.

“When conditions are this cold, birds need to use more energy and require more food,” Brooke Bateman, director of Climate Science at the National Audubon Society, told The Guardian. “[This conditions put] them at risk of not being able to sustain themselves.”

Aquatic species are also at risk, as the quick temperature drops don’t allow them to retreat into deeper, warmer waters in time. 

Meanwhile, the extreme weather presents a temporary challenge for food production, too. Ranchers across the US raced against time over the weekend to bring their cattle to shielded areas and provide them with more food that will make them more resilient to the freezing temperatures, while farmers said they were worried that the frigid temperatures may damage dormant wheat crops that lack a protective layer of snow.

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