Strange days have reached Ny-Alesund, Europe's most northerly research station. Perched at the very edge of the continent, in Svalbard, Norway, a mere 600 miles from the North Pole, the centre's international scientists have been experiencing weather that is becoming increasingly unpredictable.
The archipelago should still be gripped by ice and screaming winds. But to their surprise, researchers have found conditions on Svalbard have been balmy and calm. Last month, Vigdis Tverberg of the Norwegian Polar Institute, reported that waters in the Kongsfjorden - the long strip of water that pokes eastwards into mainland Svalbard at Ny-Alesund - were now 2C warmer than they used to be a few years ago.
Two degrees may seem a modest rise, but the effects are profound, as Tverberg stressed: 'Normally, the temperature in the fjord would be close to freezing. This winter the cooling of the water has probably never been close enough to produce an ice cover.'
Thus a major strip of water, on a latitude parallel to the northernmost tip of Greenland, failed to produce a covering of ice this year. The inference is clear, say researchers. Global warming, driven by increasing levels of carbon dioxide in the atmosphere, is not only increasing air temperatures, it is causing the oceans to warm alarmingly.
For years, scientists have stressed the Arctic and the Antarctic are the most climatically sensitive parts of our planet. Global warming was always going to hit the poles with disproportionate severity, they said. Now those predictions are being proved correct, not just in the warming waters off Svalbard but in the melting glaciers of Greenland and the disappearing ice sheets of west Antarctica. In the case of Greenland, scientists at Nasa and the University of Kansas reported this year that previous estimates of the rate of melting of Greenland's glaciers had been too low and too optimistic in assuming it would take centuries to heat and melt its massive ice shield.
Instead, when Nasa's Eric Rignot, and Pannir Kanagaratnam, of Kansas University, studied Greenland's glaciers, they uncovered an unexpected effect. As air temperatures have risen - roughly 3C in the Arctic over the past two decades - the resulting meltwater has poured to the bases of glaciers and acted as a lubricant. Thus the marches to the sea of these great rivers of ice are being accelerated, raising the amount of ice dumped in the Atlantic each year from 100 cubic kilometres in 1996 to 220 last year.
Neither is the Antarctic exempt. In March, scientists from the University of Colorado at Boulder, using satellites to monitor tiny fluctuations in Earth's gravity, concluded that the continent is now losing similar amounts of ice, about 150 cubic kilometres a year.
Yet there may be even more worrying, more serious effects triggered by the disappearance of the polar ice caps. Those vast sheets of bright, white ice make near-perfect mirrors that shine back 80 per cent of the sunlight that falls on them. Thus they help to keep our planet cool. This measure of reflectivity is known as albedo (from the Latin word for whiteness). A perfect reflector would have an albedo of 1.0, The albedo for polar ice is around 0.8. By contrast, the albedo for sea water is around 0.07.
The difference between these two figures is stark. Ice has one of the highest albedos of any substance on Earth, sea water has one of the lowest, so we are replacing our planet's best reflector with one of the worst.
And in America we have an Administration editing federal reports (by a non-scientist political hack) to downplay this issue. You still hear the chant from the far-right Republicans that Global Warming is unsupported by present evidence and needs "more study." They are in total denial and we are running out of time to do anything meaningful.
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