Nature
PUBLISHED
5
Just a few weeks ago, a major report found that Antartica is losing six times as much ice each year than 40 years ago. It turns out, the situation isn’t much better in the farthest stretches of the northern hemisphere either.
The rest of this article is behind a paywall. Please sign in or subscribe to access the full content.New research has shown that Greenland’s ice is melting far faster than scientists previously thought and could become a major contributor to sea level rise around the world within just two decades.
Worse of all, it looks like it’s too late to do anything about it.
“The only thing we can do is adapt and mitigate further global warming – it's too late for there to be no effect," Michael Bevis, lead author of the paper, and professor of geodynamics at Ohio State University (OSU), said in a statement.
"This is going to cause additional sea level rise. We are watching the ice sheet hit a tipping point."
As reported in the Proceedings of the National Academy of Sciences this week, scientists led by OSU reached this grim conclusion by looking at satellite data revealing changes in ice mass in southwest Greenland, an area of the island once believed to be relatively stable as it doesn’t have many large glaciers.
They found that by 2012, ice was being lost at nearly four times the rate to that of 2003. Between 2002 and 2016, Greenland lost around 280 gigatons of ice per year – that’s enough to increase sea levels by 0.076 centimeters (0.03 inches) each year.
The leading cause of the big melt is – you guessed it – a rise in global temperature caused by climate change. However, this is being combined with an erratic natural weather phenomenon known as the North Atlantic Oscillation, which causes fluctuations in atmospheric pressure at sea level and can increase melting. Typically, these weather events can pass without too much bother, but climate change is now “supercharging” these phenomena, making their effects even more profound.
“These oscillations have been happening forever,” Bevis added. “So why only now are they causing this massive melt? It’s because the atmosphere is, at its baseline, warmer. The transient warming driven by the North Atlantic Oscillation was riding on top of more sustained, global warming.”
Summertime temperatures in Greenland are affecting parts of the country that were previously thought stable, and the North Atlantic Oscillation has given that extra shove, causing large areas of ice to melt.
Bevis argues that we're on a very slippery slope downwards – almost a point of no return – where irreversible changes have shifted the environment and cycles of weather, which will only continue to make Greenland's ice melt at an increasing rate. Now, it's all about damage limitation.
“We’re going to see faster and faster sea level rise for the foreseeable future,” Bevis grimly summed up. “Once you hit that tipping point, the only question is: How severe does it get?”
