A new study published this week in the Proceedings of the National Academy of Sciences has found that Greenland is melting four times faster than it has in the past 15 years. Using data from the Gravity Recovery and Climate Experiment (GRACE), which were two satellites launched by Germany and NASA back in 2002, researchers discovered that between 2002 and 2016, Greenland lost 280 gigatons of ice every year, and that resulted in the addition of .03 inches of water annually to the world’s oceans.
“We’re going to see faster and faster sea level rise for the foreseeable future,” study lead author and Ohio State University geodynamics professor Michael Bevis said in a press release. “Once you hit that tipping point, the only question is: How severe does it get?”
Bevis explained that they knew there was a significant problem with the increasing rates of ice discharge from the large outlet glaciers. But what they didn’t expect was ice melt from Greenland’s southwest region. That area does not normally have breaking glaciers like the southeast and northwest, yet the southwest is where the most consistent ice loss happened between 2003 and 2012.
There was also a noticeable pause in melting back in 2013, at the same time that warm air was brought to Greenland by a reversal in North Atlantic Oscillation. Bevis said that is concerning, because in the past, the cycle of warm and cool temperatures didn’t have such a dramatic impact on the region. If the base-level temperature is so warm that the natural temperature cycles are accelerating the ice melting, then this could be a “tipping point.”
However, the authors of another study from December 2018 cautioned using such language. They found that Greenland was melting at the fastest rate in more than three centuries, but that doesn’t mean we have passed “the point of no return,” according to the study authors.
Woods Hole Oceanographic Institute scientist Sarah B. Das said that there are still meaningful actions humans can take. If we limit greenhouse gas emissions, we can limit global warming. This will make a big difference in how quickly the ice melting in Greenland will affect the rise of sea levels.
Image via Christine Zenino