Yes, I know you’ve all heard we’ve had “record” refreezing of Arctic ice. Big shock, there. We had record melting followed by a temporary cooling La Niña event. What those denier/delayer-1000 talking points don’t tell you is that the refrozen ice is very thin and still at record low levels following the staggering ice loss this summer.
To set the record straight, on Wednesday, the National Snow and Ice Data Center and NASA had a teleconference to show the surprising and alarming new data from NASA’s ICESat satellite, which revealed over the past year “the steepest yearly decline in perennial [i.e. old, thick] ice on record” (click to enlarge):
The key point is that ice volume is ice area times ice thickness. The seasonal ice (1 year or less old) is thinner and will quickly melt away and disburse in the wind. This is global warming, folks:
On March 18 the scientists said they believe that the increased area of sea ice this winter is due to recent weather conditions, while the decline in perennial ice reflects the longer-term warming climate trend and is a result of increased melting during summer and greater movement of the older ice out of the Arctic.
The Washington Post has a must-read story on this today:
“Because we had a cold winter, the public might think things have gotten better,” said Walter Meier of the National Snow and Ice Data Center at the University of Colorado at Boulder. “In fact, the loss of the perennial ice makes clear that they’re not getting better at all.“
The surprising drop in perennial ice makes the fast-changing region more unstable, because the thinner seasonal ice melts readily in summer….
Flying over the Arctic, one might perceive the sea ice cover as broad, Meier said, but that apparent breadth hides the fact that the ice is so thin. “It’s a facade, like a Hollywood set,” he said. “There’s no building behind it.”
All of this thinning data comes comes on the heel the February data reported from NOAA’s National Climactic Data Center, which pointed out that the area of Arctic ice is still historically small: