Mentre sul corriere e gli altri quotidiani nazionali si legge dell’ultima sparata di Berlusconi (le precedenti, ricordo, erano i brogli elettorali e la tempistica di caduta del governo) , qui ogni giorno il Sydney Morning Herald, quotidiano progressista di Sydney, non fa che parlare del drammatico cambiamento climatico. Ecco cosa ha scritto l’altroieri:
ARCTIC ice at the North Pole melted at a record rate in the northern summer, the latest sign that climate change has accelerated, scientists say.
“In 2007 we had off-the-charts warming,” Michael Steele, a University of Washington oceanographer, said at the American Geophysical Union’s annual meeting in San Francisco, where 15,000 researchers have gathered to discuss earthquakes, water resources and climate change.
It had been an ominous summer; for the first time in recorded history, ships sailed across water that had been part of the polar ice cap, said Donald Perovich, of the US Army Cold Regions Research and Engineering Laboratory in New Hampshire.
While in the summer of 1980 the pole was covered by an ice sheath about the size of the continental US, this summer the ice would not have covered the states west of the Mississippi, he added.
“It’s a tremendous decrease, but of course the mystery is how did it happen?” Dr Perovich said.
Just last year two leading scientists surprised colleagues by projecting that the Arctic sea ice was melting so rapidly that it could disappear by the summer of 2040.
This week, after reviewing his new data, the NASA climate scientist Jay Zwally said: “At this rate, the Arctic Ocean could be nearly ice-free at the end of summer by 2012.”
Greenland’s ice sheet melted nearly 19 billion tonnes more than the previous high mark.
Scientists said two main factors were accelerating the vanishing of the ice pack, which helps cool the Earth by reflecting the sun’s rays back into the atmosphere. As temperatures in the Pacific and Atlantic rise, warmer water moves into the Arctic Ocean. This helps melt the ice cap, which this year floated in water about 3.5 degrees warmer than its historical mean, Dr Steele said.
John Walsh, of the University of Alaska, Fairbanks, said: “Water that is now circulating just 200 metres below the main ice pack is now significantly warmer than it was just five years ago.”
As ice melts to water, it reflects only 7 per cent of the sun’s radiation, much less than the 85 per cent that ice normally reflects.