Greenland’s glaciers held 75% of the world’s freshwater before humans started pumping greenhouse gases into the atmosphere in high volumes, at the beginning of the Industrial Age. Since then, Greenland has been melting, but the melting has sped up considerably now. The New York times produced an in-depth multi-media report on Greenland’s ice sheets.
Now, a massive glacier in Greenland is on the very verge of collapse, researchers have found. From 1996 to 2010, the edge of the glacier lost 2.2 miles into the ocean. But over just the next five years, it lost another 2.2 miles. The rapidly diminishing ice block, Zachariae Isstrom, has enough mass to raise the level of sea by nearly two feet.
“The destabilization of this marine-based sector will increase sea-level rise from the Greenland Ice Sheet for decades to come” the researchers write in their report, published Thursday in Science.
The depletion of Greenland’s glaciers is due largely to warming ocean waters, the researchers said. According to earlier studies, 90 percent of global warming is taking place in the ocean. Because Greenland’s glaciers extend deep into the ocean, they are particularly exposed to changing temperatures. (Hot tip: When you’re trying to defrost a frozen steak, putting it in water will massively speed up the process. The same process is at work here.)
“North Greenland glaciers are changing rapidly,” lead author Jeremie Mouginot, an associate project scientist in the Department of Earth System Science at the University of California, Irvine, said in a statement. “The shape and dynamics of Zachariae Isstrom have changed dramatically over the last few years. The glacier is now breaking up and calving high volumes of icebergs into the ocean, which will result in rising sea levels for decades to come.”
There are actually two glaciers rapidly depleting in the northeast section of Greenland: the Zachariae Isstrom and Nioghalvfjerdsfjorden. Combined, they represent more than three feet of sea level rise. There are also glaciers melting on the west side of the country. Altogether, the ice sheet of Greenland holds enough water to raise sea levels by 20 feet.
“If you see Greenland as a boat, it’s like we’re taking water from every side now,” Jeremie Mouginot, an author of the report from the University of California-Irvine, told the Washington Post.
A century’s worth of data analyzed in a study over the summer showed that the world’s glaciers are melting faster than now they ever have before. Even if global warming stopped today, they would continue to melt, the researchers found.
That is obviously bad news for sea level rise. It’s amazing to think that glaciers up in Greenland hold enough water to inundate our entire coastline, but it’s true. A mapping tool released in September gives users an opportunity to see what their city will look like under different sea level scenarios. The project posits that without global action, carbon pollution cause sea level to rise 14 to 33 feet — but even at smaller numbers, U.S. cities such as New Orleans and Miami are likely to be threatened, and it could be too late to stop it.