This year's record ice melts in
Greenland and the Arctic ocean aren't flukes, but confirmation that
the Arctic is racing ahead into a new and unknown climate state, said
top US climate scientists today.
The announcement came with the release
today of the 2012 Arctic Report Card, which calls on the expertise of
140 scientists from 15 countries to summarize the state of the
Arctic.
“If we are not already there, we're
clearly on the verge of seeing a new Arctic,” said Martin Jeffries
of the Office of Naval Research. Jeffries and other scientists spoke
at a press conference today at the meeting of the American
Geophysical Union in San Francisco.
Highlights from the 2012 report include
low snow coverage in June and record
low sea ice extent in September, a longer
growing season with greener tundra, record
high permafrost temperatures in northernmost Alaska,
melt season ever seen on the Greenland ice sheet and a
nearly ice sheet-wide melt event in July.
What's more, the thinner sea ice is
letting more light through to the water, which is leading to masssive
phytoplankton blooms in the summer that could mean the
productivity at the bottom of the food chain of those waters is ten
times what was previously thought. On land the arctic
fox is close to extinction in Fennoscandia — the region that includes the Scandinavian Peninsula, Finland, Karelia, and the Kola Peninsula — and falling
prey to the larger Red foxes moving north with warmer temperatures.
The Arctic fox is also suffering as a result of changes in the
lemming cycle, which is an important food source for the small
predator.
There were even severe
weather events including extreme cold and snowfall in
Eurasia and two major storms off western and northern Alaska.
“2012 has been an astounding year,”
said Jason Box, who studies Greenland at the Byrd Polar Research
Center at Ohio State University. It was the warmest summer in 170
years, he said, and the vast extent of melting ice seems to indicate
something has fundamentally changed. “This year Greenland crossed a
threshold. We can expect Greenland to be melting across its entire
surface from now on.”
The loss of all this ice in the Arctic
is not simply a consequence of global warming, however, it also adds
to the problem. Ice and snow are terrific reflectors that keep a lot
of solar energy from being trapped in Earth's atmosphere. When ice
melts, darker ground and waters are exposed and absorb that sunlight.
“The Arctic is one of the Earth's
mirrors and that mirror is breaking,” said researcher Donald
Perovich of Dartmouth College.
