Adam Norfolk9 Column Grid

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DefrostsFreezerThe

Dramatic melting of sea ice due to global warming is having a major impact on the polar regionjohn vidal

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environmentalist

With the melt happening at an

unprecedented rate of more

than 100,000 sq km a day, and

at least a week of further melt

expected before ice begins to

reform ahead of the northern

winter, satellites are expected to

confirm the record – currently

set in 2007 – within days.

“Unless something really unusual happens we

will see the record broken in the next few days.

It might happen this weekend, almost certainly

next week,” Julienne Stroeve, a scientist at the US

National Snow and Ice Data Centre (NSIDC) in

Boulder, Colorado, told the Guardian.

“In the last few days it has been losing 100,000

sq km a day, a record in itself for August. A storm

has spread the ice pack out, opening up water,

bringing up warmer water. Things are definitely

changing quickly.”

Because ice thickness, volume, extent and area are

all measured differently, it may be a week before

there is unanimous agreement among the world’s

cryologists (ice experts) that 2012 is a record

year. Four out of the nine daily sea ice extent and

area graphs kept by scientists in the US, Europe

and Asia suggest that records have already been

broken. “The whole energy balance of the Arctic

is changing. There’s more heat up there. There’s

been a change of climate and we are losing more

seasonal ice. The rate of ice loss is faster than the

models can capture [but] we can expect the Arctic

to be ice-free in summer by 2050,” said Stroeve.

Arctic sea ice is set to reach its lowest ever recorded extent as early as this weekend, in “dramatic changes” signalling that man-made global warming is having a major impact on the polar region.

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“We can expect the Arctic

to be ice-free in summer by 2050 ”

“Only 15 years ago I didn’t expect to see such

dramatic changes – no one did. The ice-free

season is far longer now. Twenty years ago it

was about a month. Now it’s three months.

Temperatures last week in the Arctic were 14C,

which is pretty warm.”

Scientists at the Danish Meteorological Institute,

the Arctic Regional Ocean Observing System in

Norway and others in Japan have said the ice

is very close to its minimum recorded in 2007.

The University of Bremen, whose data does not

take into account ice along a 30km coastal zone,

says it sees ice extent below the all-time record

low of 4.33m sq km recorded in September 2007.

Ice volume in the Arctic has declined dramatically

over the past decade. The 2011 minimum

was more than 50% below that of 2005.

According to the Polar Science Centre at the

University of Washington it now stands at around

5,770 cubic kilometres, compared with 12,433 cu

km during the 2000s and 6,494 cu km in 2011.

The ice volume for 31 July 2012 was roughly

10% below the value for the same day in 2011.

A new study by UK scientists suggests that 900 cu

km of summer sea ice has disappeared from the

Arctic Ocean over the past year.

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environmentalist

The consequences of losing the Arctic’s ice coverage for the summer

months are expected to be immense. If the white sea ice no longer

reflects sunlight back into space, the region can be expected to heat

up even more than at present. This could lead to an increase in

ocean temperatures with unknown effects on weather systems in

northern latitudes.

In a statement, a Greenpeace spokesman said: “The disappearing

Arctic still serves as a stark warning to us all. Data shows us that the

frozen north is teetering on the brink. The level of ice ‘has remained

far below average’ and appears to be getting thinner, leaving it more

vulnerable to future melting. The consequences of further rapid ice

loss at the top of the world are of profound importance to the whole

planet. This is not a warning we can afford to ignore.”

Longer ice-free summers are expected to open up the Arctic ocean

to oil and mining as well as to more trade. This year at least 20

vessels are expected to travel north of Russia between northern

Europe and the Bering straits. Last week a Chinese icebreaker made

the first voyage in the opposite direction.

“Every one of the 56,000 Inuits in Greenland have had to adapt to

the retreat of the ice,” said Carl-Christian Olsen, president of the

Inuit Circumpolar Council in Nuuk, Greenland. “The permafrost is

melting and this is jeopardising roads and buildings. The coastline

is changing, there is more erosion and storms, and there are fewer

mammals like polar bears. It means there can be more mining,

which is good for the economy, but it will have unpredictable effects

on social change”.

Research published in Nature today said that

warming in the Antarctic peninsula, where

temperatures have risen about 1.5C over the past

50 years, is “unusual” but not unprecedented

relative to natural variation. The research by

Robert Mulvaney of the British Antarctic Survey,

Cambridge, based on an ice-core record, showed

that the warming of the north-eastern Antarctic

peninsula began about 600 years ago.

The

coastline is

changing,

there is more

erosion

and storms,

and there

are fewer

mammals

like polar

bears.