The ongoing destruction of the Arctic sea ice appears to be in full swing this summer. So any relief due to a cold continental winter turns out to be non existent.
As i predicted in 2007 even
before the perfect storm that gave us the record low, the sea ice is on a
downward spiral that will be much shorter than even these predictions here. The thick ice is already mostly gone and is
into the last stages and await the right wind conditions to produce a dramatic
reduction.
My normal monitoring source has
not been up this year so I am lagging behind, but this will be big news once
everyone wakes up to what is now happening.
Spring breakup is under way in
the Arctic , although the past three years
masked it all because the ice loss was ongoing but the surface cover was
maintained. That is now collapsing.
It has been clear for some time
that total ice mass is a terribly suspect science. If we are actually losing as much as
suggested by earlier work, then we are in the final laps and the seas will be
quite clear beginning as early as next year and certainly over the next several
years. As usual no one understands the nature of a non linear decay.
Arctic may be ice-free within 30 years
From the
Guardian
Jul 13, 2011
Sea ice in the Arctic is melting at a record pace this year, suggesting warming at the north pole is speeding up and a largely ice-free
The area of the Arctic ocean at least 15% covered in ice is this
week about 8.5 m sq kilometres – lower than the previous record low
set in 2007 – according to satellite monitoring by the US National Snow and Ice Data Centre (NSIDC)
in Boulder, Colorado. In addition, new data from the University of Washington
Polar Science Centre
In the past 10 days, the Arctic ocean
has been losing as much as 150,000 square kilometres of sea a day, said
Mark Serreze, director of the NSIDC.
"The extent [of the ice cover] is going down, but it is also
thinning. So a weather pattern that formerly would melt some ice, now gets rid
of much more. There will be ups and downs, but we are on track to see an
ice-free summer by 2030. It is an overall downward spiral."
Global warming has been melting Arctic sea ice for the past 30 years at
a rate of about 3% per decade on average. But the two new data sets suggest
that, if current trends continue, a largely ice-free Arctic
in summer months is likely within 30 years. That is up to 40 years earlier than
was anticipated in the last Intergovernmental Panel on Climate Change (IPCC)
assessment report.
Sea ice, which is at its maximum extent in March and its lowest in
September each year, is widely considered to be one of the "canaries in
the mine" for climate change, because the poles are heating up faster than
anywhere else on Earth. According to NSIDC, air temperatures for June 2011 were
between 1 and 4 °C warmer
than average over most of the Arctic Ocean.
The findings support a recent study in the journal Science that
suggested water flowing from the Atlantic into the Arctic ocean is warmer today than
at any time in the past 2,000 years and could be one of the explanations
for the rapid sea ice melt now being observed.
Computer simulations performed by Nasa suggest that the retreat of
Arctic sea ice will not continue at a constant rate. Instead the simulations
show a series of abrupt decreases such as the one that occurred in 2007, when a
"perfect storm" of weather conditions coincided and more ice was lost
in one year than in the previous 28 years combined. Compared to the 1950s, over
half of the Arctic sea ice had disappeared.
What concerns polar scientists is that thicker ice which does not
melt in the summer is not being formed fast as the ice is melting. On
average each year about half of the first year ice, formed between September
and March, melts during the following summer. This year, says Jeff Masters,
founder of the Weather Underground climate monitoring website, a high pressure
system centred north of Alaska has brought clear skies and plenty of
ice-melting sunshine to the Arctic.
"The combined action of the clockwise flow of air around the high
and counter-clockwise flow of air around a low pressure system near the western
coast of Siberia is driving warm, southerly winds into the Arctic that is
pushing ice away from the coast of Siberia, encouraging further melting."
Sea ice has an important effect on the heat balance of the polar oceans, since it insulates the
(relatively) warm ocean from the much colder air above, thus reducing heat loss
from the oceans. Sea ice also has a high albedo – about 0.6 when bare, and
about 0.8 when covered with snow – compared to the sea – about 0.15 – and thus
the loss of sea ice increased the absorption of the sun's warmth by the sea.
This article was shared by our content partner the Guardian. environmentalresearchweb is
now a member of the Guardian
Environment Network.
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