The North and South Poles both reported extreme warm temperatures over the weekend, reaching record highs that alarmed climate scientists.
The Concordia research base, a French-Italian research facility and the most remote research base in the world, reported a record -11.5 degrees celsius (11.3 degrees Fahrenheit) on Friday, climate researcher Stefano Di Battista tweeted that day. That’s about 70 degrees warmer than average, the Washington Post first reported—Eastern Antarctica, where Concordia is based, typically reports temperatures around minus-50 or minus-60 this time of year. Temperatures nearing zero or 10 degrees celsius constitute a “massive heat wave,” the Capital Weather Gang wrote in their report on Friday evening.
As this was happening, Weather stations in the Arctic—in Norway and Greenland—also saw temperatures more than 50 degrees warmer than average. Dr. Zachary Labe, a postdoctoral researcher in atmospheric sciences at Colorado State University had his eyes on this warming trend when he got news of warming on the other side of the globe.
“The Antarctic kind of caught me by surprise,” Labe told Motherboard over the phone. “Even more anomalous, even warmer, more warmer than average in the Arctic.”
The news sent the internet into a frenzy. Di Battista, who posted Antarctic temperature updates on Twitter over the weekend, called the warming event a “brutal heat wave.” Dr. Jonathan Wille, a postdoctoral researcher in polar meteorology at the Université Grenoble Alpes tweeted that temperatures like this are “never supposed to happen.”
“This Antarctic heat wave definitely changes what we thought was possible for Antarctic weather,” Wille tweeted on Saturday.
Dr. Julie Brigham-Grette, professor at the University of Massachusetts Amherst department of geosciences and past chair of the Polar Research Board of the US National Academy of Sciences attributed the warming to the movement of the jet streams: a meandering air current that flows from west to east across the globe. Climate scientists have long posited that a changing climate is making the jet streams “wavier,” bring cold currents southward and warm currents northward. That’s what happened over the weekend, Brigham-Grette said.
“The increase in waviness means much more extreme cold air will come way far south,” she said. “And then on the other side of these large swings, the warmth can penetrate way up north. And this is what we saw happening in both hemispheres, is these extreme high temperatures. I mean, really seriously extreme temperatures.”
Specifically, Brigham-Grette says Winter Storm Quinlan, a cold front that brought snow to the East Coast of the US last weekend, moved off the coast and into the North Atlantic ocean. As it did, it sent warm air north, toward the Arctic, causing temperature spikes. Brigham-Grette had her eye on satellite images of the streams all weekend.
“It makes your jaw drop looking at it,” she said.
Labe noted that with the movement of the jet stream, an atmospheric river, or a plume of moisture and heat, moved with it. This happens regularly in the Arctic, he says.
“But this one was particularly unusual,” Labe said, noting that warming events on this scale can have long term ecosystem impacts if they get warm enough to melt swaths of sea ice.
Labe is relatively certain that this weekend’s warming in the Arctic is attributable to climate change, noting that the unusual highs in both regions are in keeping with trends coming out of the north pole. A 2017 study in the peer-reviewed journal Geophysical Research Letters found that, since 1980, the number of warming events has grown in the region—on the scale of an extra six per year, which have grown from fewer than two days in length to two and a half days.
“Climate change is loading the dice for these types of warmer and more moisture events to occur,” he said. “Certainly, it aligns with the idea that climate change would make more of these warmer and wetter events likely to occur in the future.”