Arctic Is Warming Twice As Fast As World Average
The latest word from scientists studying the Arctic is that the polar region is warming twice as fast as the average rise on the rest of the planet. And researchers say the trend isn't letting up. That's the latest from the 2014 Arctic Report Card — a compilation of recent research from more than 60 scientists in 13 countries. The report was released Wednesday by the National Oceanic and Atmospheric Administration.
Jackie Richter-Menge, a polar scientist with the U.S. Army Corps of Engineers who collaborated with NOAA on the analysis, says the findings demonstrate the "power of persistence" in the Arctic — "persistence in the warming air temperatures and the impact that is having on this icy environment."
That's largely because of arctic amplification. Here's how it works: Normally, snow and ice cool the surface by reflecting a lot of the sun's energy back up into the atmosphere. But warming air temperatures melt snow and ice. "And when they melt," says Richter-Menge, "they expose darker regions."
Darker regions, once covered in snow and ice, now absorb more heat, like a dark shirt does on a hot, sunny day. The same thing happens when sea ice melts — the exposed water is darker and warms up.
So what happens as a result of this amplification? Well, warmer water affects what lives in it. Apparently, plankton like the warmer conditions; they're thriving. Scientists say they don't know whether that's good or bad for the rest of us. But unlike plankton, polar bears don't like the warmer water and having less sea ice around.
"There's a strong connection between what's going on with the sea and polar bears," says Richter-Menge. In regions where the sea ice is holding steady, bears are doing OK, according to the report card. Where the ice is gone, bear numbers are down.
Then there's Greenland. The giant land mass is covered in ice that's a mile thick. Geophysicist Beata Csatho at the University at Buffalo has just completed the most comprehensive satellite survey of that ice cover.
"There are some places," she says, "where in the last 20 years the ice surface is just lowering, lowering, lowering very uniformly."
Csatho, whose research appears separately in the Proceedings of the National Academy of Sciences this week, says she has noticed something else about Greenland's blanket of ice: Because the ice melts from the top down, the surface elevation gets lower over time. And at lower elevations, the air generally is warmer.
"As Greenland is losing ice, it gets more and more irreversible," Csatho explains, "because you get the ice into lower and lower elevations."
The research shows some exceptions to the warming trend — places where ice is building back up or temperatures are cooling. But overall, warming is winning in the Arctic.
9(MDE1MTIxMDg0MDE0MDQ3NTY3MzkzMzY1NA001))
Transcript
RENEE MONTAGNE, HOST:
Scientists studying the Arctic say it is warming twice as fast as the rest of the planet. And they warn there are no signs of that trend letting up. NPR's Christopher Joyce has the story on the government's annual Arctic report card.
CHRISTOPHER JOYCE, BYLINE: There are no grades for the Arctic in this report card. It's more of a progress report.
JACKIE RICHTER-MENGE: We really see the power of persistence in the Arctic.
JOYCE: Jackie Richter-Menge is a polar scientist with the U.S. Army Corps of Engineers.
RICHTER-MENGE: In this particular case, persistence in the warming air temperatures and the impact that that's having on this icy environment.
JOYCE: Richter-Menge is one of more than 60 researchers from over 13 countries who collaborated with the National Oceanic and Atmospheric Administration on the report. Their conclusion...
RICHTER-MENGE: It's warming in the Arctic faster than it is anywhere on the globe.
JOYCE: That's because of Arctic amplification. Here's how it works. Normally, snow and ice cool the surface by reflecting a lot of the sun's energy back up into the atmosphere. But warming melts snow and ice.
RICHTER-MENGE: And when they melt, they expose darker regions.
JOYCE: Darker regions underneath absorb more heat, like a dark shirt on a hot, sunny day. Same thing when sea ice melts; the exposed water is darker and warms up. So what happens as a result of this amplification? Well, warmer water affects what lives in it. Apparently, plankton like it warmer. They're thriving. Unlike plankton, though, polar bears need cold water and sea ice.
RICHTER-MENGE: There's a strong connection between what's going on with regard to the sea ice cover and the polar bears.
JOYCE: Where the sea ice is holding steady, bears are doing OK. Where the ice is gone, bear numbers are down. Then there's Greenland. The giant landmass is covered in ice that's a mile thick. Geophysicist Bea Csatho at the University of Buffalo has just completed the most comprehensive satellite survey of that ice cover.
BEA CSATHO: There are some places where, in the last 20 years, the ice surface is just lowering, lowering, lowering very uniformly.
JOYCE: Csatho, whose research appears separately in the Proceedings of the National Academy of Sciences, says she's noticed something else about Greenland's blanket of ice. Because the ice melts from the top down, the surface elevation gets lower over time. And at lower elevations, the air generally is warmer.
CSATHO: As Greenland is losing ice, it gets more and more irreversible because you get the ice into lower and lower elevations.
JOYCE: The research shows some exceptions to the warming trend - places where ice is building back or temperatures are cooling. But overall, warming is winning in the Arctic. Christopher Joyce, NPR News. Transcript provided by NPR, Copyright NPR.
300x250 Ad
300x250 Ad