[asa] Major Arctic sea ice melt is expected this summer

 This has a good explanation why the ice melt is a much bigger problem in
the Arctic than the Antarctic (and why even that bit of good news is
temporary).

http://www.physorg.com/news128960273.html

By RANDOLPH E. SCHMID, AP Science Writer (AP) -- The Arctic will remain on
thinning ice, and climate warming is expected to begin affecting the
Antarctic also, scientists said Friday. "The long-term prognosis is not very
optimistic," atmospheric scientist Jennifer Francis of Rutgers University
said at a briefing.
  <http://physorg.tradepub.com/?pt=cat&page=_INTL> Last summer sea ice in
the North shrank to a record low, a change many attribute to global warming.

<http://adms.physorg.com/openads/www/delivery/ck.php?n=a7080d51&cb=INSERT_RANDOM_NUMBER_HERE>
But while solar radiation and amounts of greenhouse gases in the atmosphere
are similar at the poles, to date the regions have responded differently,
with little change in the South, explained oceanographer James Overland of
the National Oceanic and Atmospheric Administration.

What researchers have concluded was happening, was that in the North, global
warming and natural variability of climate were reinforcing one another,
sending the Arctic into a new state with much less sea ice than in the past.

"And there is very little chance for the climate to return to the conditions
of 20 years ago," he added.

On the other hand, Overland explained, the ozone hole in the Antarctic
masked conditions there, keeping temperatures low in most of the continent
other than the peninsula reaching toward South America.

  "So there is a scientific reason for why we're not seeing large changes in
the Antarctic like we're seeing in the Arctic," he said.

But, Overland added, as the ozone hole recovers in coming years, global
warming will begin to affect the South Pole also.

The briefing covered data being reported in a paper scheduled for
publication next week in Eos, a journal of the American Geophysical Union.

Overland said he used to be among those skeptical about the effects of
global climate change. The new findings, which he termed "startling," were
developed at a recent workshop, he said.

There is agreement between weather observations, the output of computer
climate models and scientific expectations for what should happen, added
Francis.

All the evidence points toward human-made changes at both poles, she said, a
conclusion that "further depletes the arsenals of those who insist that
human-caused climate change is nothing to worry about."

Climatologist Gareth Marshall of the British Antarctic Survey said that
while the term global warming is widely used, things are more complicated at
the regional level.

In the Antarctic, he explained, climate change strengthened winds blowing
around the continent, helping trap colder air. But that will decrease in the
future, allowing warmer conditions to begin, he said.

And, Marshall added, all studies now show that human activities are the
drivers of climate change in the Antarctic.

Asked if this summer will match last year's record low sea ice in the North,
Overland that is likely.

"The tea leaves point to a minimal amount of sea ice next September, that
would be the same as we had last summer, 40 percent loss compared to 20
years ago," he said. Overland added that the winter freeze got a late start
last fall.

Francis added: "Over this entire fall, winter and right up 'till today the
ice concentration, the amount of ice that's floating around on the Arctic,
has been below normal every single day."

"All arrows are pointing towards, certainly not a recovery, something like
we had last summer and possibly worse," she said.

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Received on Fri May 2 17:08:43 2008