Extreme arctic temperatures become the new norm
A group of scientists studying a broad range of Arctic systems — from sea ice to permafrost to the Greenland ice sheet — gathered in D.C. Wednesday to lay out just how extreme a year 2016 has been so far for the northern cap of the planet.
“We’ve lost about twice the size of the state of Alaska in terms of area,” said Walt Meier, a scientist with NASA who studies Arctic sea ice, referring to the long-term trend in Arctic sea ice over the past several decades. “It’s also thinning as well, we’ve lost about 50 percent of the thickness. And this is happening more rapidly than even the most aggressive climate models.”
A series of researchers covering other Arctic systems then proceeded to tell very similar tales:
* For Greenland, April through June temperatures were about 3 degrees Celsius above the long-term average—a new high. The surface temperature set new records for April to June 2016.
* For Northern Hemisphere snow cover, the spring of 2016 set a new record low, losing snow earlier than any time in record … throughout the Northern Hemisphere.
* For thawing permafrost — carbon-packed soil layers that have the potential to spill even more greenhouse gases into the atmosphere as they warm — 2015 showed record high temperatures in measuring sites in Alaska and 2016 is shaping up as a new record year.
* For the Northern Hemisphere jet stream, which appears to be becoming more wavy and loopy in nature as the Arctic warms faster than the mid-latitudes, the difference in the temperature change between the Arctic and the mid-latitudes is at an all-time record high.
The most troubling aspect of all of this, and a recurrent theme of the talks, was the researchers’ emphasis on how changes in the Arctic are not necessarily linear in nature as global warming grows — once you cross the freezing point, notes Robinson, it’s a total phase change for water, plain and simple — and that the system is laden with feedback processes, which amplify themselves.
All of this, and yet as the researchers repeatedly acknowledged, the truth is that 2016 is just one of several years showing extraordinary change in the fastest-warming part of the planet — 2012 still holds the record for the all-time low in Arctic sea ice extent and the all time maximum for Greenland melting, for instance. So it’s not so much that 2016 is so completely outside of all prior experience — but rather, that it’s yet another indicator of a new reality.
“The extraordinary years have become the normal years,” said NASA’s Meier.
For more on this story go to: http://www.thecarbonwars.com/extreme-arctic-temperatures-become-the-new-norm/