2016 looks sure to go down as the hottest year on record, and the Arctic hasn't been spared. That region saw "unprecedented" warming air temperatures that delayed the fall freeze-up, according to a new report from the US National Oceanic and Atmospheric Administration (NOAA), which released its annual Arctic Report Card on Tuesday.
"We've seen a year in 2016 in the Arctic like we've never seen before," Jeremy Mathis, director of NOAA's Arctic Research Program, told journalists at the American Geophysical Union's fall meeting in San Francisco. "It clearly shows a stronger and more pronounced signal of persistent warming than in other previous year in our observational record."
That warming has had what he called a "cascading effect" through the Arctic environment, impacting its ecosystems and the people who call it home.
Arctic Report Card 2016. Video: NOAAPMEL/YouTube
Given President-elect Trump's controversial pick for Secretary of State—ExxonMobil CEO Rex Tillerson is keen to drill for more oil there—this peer-reviewed report on how the Arctic is changing comes at a critical time. When a reporter questioned the panel on whether the research could have an impact on the incoming administration, Mathis didn't take the bait. The Arctic Report Card is "for the American people," he said, adding that it's been produced for 11 straight years now, and gave every indication that would continue. This year, 61 scientists from 11 countries were involved in putting it together.
"This is the best possible science we can do," Mathis said.
What the science shows is alarming. For one thing, the average annual air temperature over Arctic land areas was the highest on record—an increase of 3.5℃ since 1900. (Arctic temperatures are rising at double the rate of global temperatures.) Spring snow cover set a record low in the North American Arctic, and the Greenland ice sheet continued to shed its mass, as it has each year since scientists started tracking this by satellite, in 2002.
"The melting season is stretched," explained Marco Tedesco, professor at Columbia University's Lamont-Doherty Earth Observatory. While this year's strong El Niño probably played a role in what scientists saw happening in the Arctic, there's still work to do to understand how big of a factor it was, Mathis continued.
Arctic sea ice is rapidly thinning. Multi-year ice, which is the hardier type, now makes up just 22 percent of the ice cover—compared to 45 percent in 1985, according to the scientists. The sea ice minimum from mid-October to late November was the lowest dating back through the entire satellite record, to 1979. Thinning ice can be catastrophic for animals that live in the North, and for Inuit communities, who rely on it for hunting and travel, a way of life.
Melting ice also speeds up the warming process, creating a dangerous kind of feedback loop. That's because white ice reflects some of the sun's energy back into space, Donald Perovich, adjunct professor of engineering at Dartmouth College, explained. "When it melts away, it goes from being a good reflector to a good absorber. [The exposed water] absorbs over 90 percent of sunlight."
The Arctic is warming faster than anywhere else on Earth. As scientists noted in the press conference, a cruiseship carried tourists through the Northwest Passage in 2016, a route that for a long time was considered impassable. No one can really say right now what the Arctic will look like in 10 or 20 years, but they agreed on this—not only is the region is changing, it's already unrecognizable from what it was just a few years ago.
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