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THE FREEZER DEFROSTS

The FreezerDefrosts

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

John Vidal

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

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.

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THE FREEZER DEFROSTS

Julienne Stroeve, from the National Snow and Ice Data Centre in Colorado, is here to track and “characterise” the ice we pass though. She mostly works from satellite data, but they can’t tell the quality or age of the ice or the way it is moving.

Greenpeace has its own plans, which I can’t divulge, but what ice pilot Arne Sorensen is looking for is a stable ice floe at least two metres thick, 100 yards long and a little less wide.

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

THE FREEZER DEFROSTS

Ice caps are melting at a rate of 100,000 square kilometers a day, putting stress on the survival rate of polar bears

The difference between the rate of warming at the two poles is attributed to geographical differences. “Antarctica is a continent surrounded by water, while the Arctic is an ocean surrounded by land. Wind and ocean currents around Antarctica isolate the continent from global weather patterns, keeping it cold. In contrast, the Arctic Ocean is intimately linked with the climate systems around it, making it more sensitive to changes in climate,” said a spokesman for the NSIDC.After setting out from northern Norway last week to witness this year’s record sea melt in the Arctic, we reached the edge of the Arctic polar ice cap this morning. It’s far further north than expected, at around 82 degrees N, but the annual sea ice retreat here has been nowhere near as great as on the Alaskan side of the ice cap, where it has dramatically pulled back hundreds of miles further than usual.The plan was to send our Danish ice pilot and a photographer up in a helicopter to examine the ice scape, but it was far too foggy and the Norwegian chopper pilot wasn’t going up for anyone.There has been much to see, though. Like two polar bears hunting just 150 yards from the boat. We sounded a respectful warning horn as we passed them on our port ride but they barely recognised us.

ARC

TIC

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There has been much to see, though. Like two polar bears hunting just 150 yards from the boat. We sounded a respectful warning horn as we passed them on our port side but they barely registered us.

ulienne 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.

JA

RCTIC“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.