Here are some clues that Arctic climate change no longer moves at a glacial pace:
- The Arctic Ocean is losing its sea ice faster, with September recording the smallest extent in modern history. It beat the previous minimum seen in 2005 by 23 percent — losing an area as large as Texas and California combined.
- This loss of ice is moving faster than predictions, accelerating beyond the pace suggested by rising greenhouse gas concentrations.
- The remaining ice is thinner, more fragile, more vulnerable to melting in future summers.
- Get ready polar bears and Native hunters: An ice-free Arctic Ocean could arrive by 2030 — about half a century ahead of previous worst-case, nightmare scenarios.
These startling details came out during a Nov. 26 panel discussion at the Dirksen Senate Office Building Washington, D.C., called Arctic Sea Ice Melt and Shrinking Polar Ice Sheets: Are Observed Changes Exceeding Expectations?
The forum — which included the senior research scientist Mark Serreze from the National Snow and Ice Data Center — was part of the Environmental Science Seminar Series sponsored by the American Meteorological Society.
Among other things, the presentation detailed how Alaskan glaciers, western and peninsula Antarctic ice and the Greenland ice sheet have both been thinning, losing mass and melting back faster than scientists predicted.
“The gravity observations show the Greenland ice sheet is losing significant mass at the low elevation coastal regions that is not compensated for by gains in the high elevation interior,” the summary states at one point.
(And this loss) “has most likely been accelerating since the mid 1990s. Although Greenland has been thickening at high elevations, because of the predicted increase in snowfall, this gain is more than offset by an accelerating mass loss, with a large component from rapidly-thinning and accelerating outlet glaciers.”
A highlight of any web-based followup to the seminar would be to cruise through the PDF version of Serreze’s presentation. It’s a series of graphics detailing the incredible loss of ice extent and thickness and the consequences. “Are we reaching a tipping point?” one slide asks, with the 2007 ice extent trend line plunging like a rock in comparison to the much slower and irregular decline of supercomputer projections.
Konrad Steffen presented on the Greenland Ice Sheet. And here is a presentation on changes in ice mass detected by satellites, by Scott B. Luthcke, from NASA’s Goddard Space Flight Center.
For media coverage of the seminar, check out this radio dispatch by APRN’s Joel Southern, which includes lively remarks by Serreze.
For those with one of those new-fangled highspeed Internet connections, as well as 102 minutes to spare, C-span also archived the forum for download and web replay.