Have 10 Years To Save The Planet
By Michael McCarthy
& David Usborne
15 September 2006
melting of the sea ice in the Arctic, the clearest sign so far of global
warming, has taken a sudden and enormous leap forward, in one of the
most ominous developments yet in the onset of climate change.
Two separate studies by Nasa,
using different satellite monitoring technologies, both show a great
surge in the disappearance of Arctic ice cover in the last two years.
One, from the Jet Propulsion
Laboratory in California, shows that Arctic perennial sea ice, which
normally survives the summer melt season and remains year-round, shrank
by 14 per cent in just 12 months between 2004 and 2005.
The overall decrease in the
ice cover was 720,000 sq km (280,000 sq miles) - an area almost the
size of Turkey, gone in a single year.
The other study, from the
Goddard Space Flight Centre, in Maryland, shows that the perennial ice
melting rate, which has averaged 0.15 per cent a year since satellite
observations began in 1979, has suddenly accelerated hugely. In the
past two winters the rate has increased to six per cent a year - that
is, it has got more than 30 times faster.
The changes are alarming
scientists and environmentalists, because they far exceed the rate at
which supercomputer models of climate change predict the Arctic ice
will melt under the influence of global warming - which is rapid enough.
If climate change is not
checked, the Arctic ice will all be gone by 2070, and people will be
able to sail to the North Pole. But if these new rates of melting are
maintained, the Arctic ice will all be gone decades before that.
The implications are colossal.
It will mean extinction in the wild - in the lifetime of children alive
today - for one of the world's most majestic creatures, the polar bear,
which needs the ice to hunt seals.
It means the possibility
of a lethal "feedback" mechanism speeding up global warming,
because the dark surface of the open Arctic ocean will absorb the sun's
heat, rather than reflect it as the ice cover does now - and so the
world will get even hotter.
But most of all, the new
developments add to the growing concern that climate change as a process
is starting to happen much faster than scientists considered it would,
even five years ago when the UN's Intergovernmental Panel on Climate
Change published its last report.
"These are the latest
in a long series of recent studies, all telling us that climate change
is faster and nastier than we thought," said Tom Burke, a former
government green adviser and now a visiting professor at Imperial College
London. "An abyss is opening up between the speed at which the
climate is changing and the speed at which governments are responding.
"We must stop thinking
that this is just another environmental problem, to be dealt with when
time and resources allow, and realise that this is an increasingly urgent
threat to our security and prosperity."
Yesterday, Jim Hansen, the
leading climatologist and director of the Goddard Institute for Space
Studies, in New York, issued a now-or-never warning to governments around
the world, including his own, telling them they must take radical action
to avert a planetary environmental catastrophe. He said it was no longer
viable for nations to adopt a "business as usual" stance on
"I think we have a very
brief window of opportunity to deal with climate change ... no longer
than a decade, at the most," he said.
Early in his first term,
President George Bush pulled the US out of the Kyoto Treaty that is
meant to bind nations to lower emissions of warming gases. However,
opinion in the US is starting to change, as evidenced by the huge success
of the documentary on climate change, An Inconvenient Truth, narrated
by the former US vice-president Senator Al Gore.
The two Nasa Arctic studies,
released simultaneously, break fresh ground in dealing with the perennial,
or "multi-winter" ice, rather than the "seasonal"
ice at the edge of the icefield, which melts every summer.
Concern about the melting
rate has hitherto focused on the seasonal ice, whose summer disappearance
and retreat from the landmasses of Arctic Canada and Siberia is increasingly
obvious. In September 2005, it retreated to the lowest level recorded.
Such rapid shrinkage of the perennial ice has not been shown before.
"It is alarming," said Joey Camiso, who led the Goddard study.
"We've witnessed sea ice reduction at 6 per cent per year over
just the last two winters, most likely a result of warming due to greenhouse
Dr Son Nghiem, who led the
team which carried out the Jet Propulsion Laboratory study, said that
in previous years there had some variability in the extent of perennial
Arctic ice. "But it is much smaller and regional," he said.
"However, the change we see between 2004 and 2005 is enormous."
Britain's Professor Julian Dowdeswell, the director of the Scott Polar
Research Institute in Cambridge, agreed the changes shown in the American
studies were "huge", adding: "It remains to be seen whether
the rate of change is maintained in future years."
The melting of the Arctic
ice will not itself contribute to global sea-level rise, as the ice
floating in the sea is already displacing its own mass in the water.
When the ice cube melts in your gin and tonic, the liquid in your glass
does not rise.
There are great volumes of
land-based ice - the ice sheets of Greenland and Antarctica, and mountain
glaciers - which are subject to exactly the same temperature rises as
the Arctic ice, and which have also started to melt. They will add to
sea levels. The West Antarctic Ice Sheet would, if it were to collapse,
raise sea levels around the world by 16ft (5m), submerging large parts
of Bangladesh and Egypt - and London.
© 2006 Independent News
and Media Limited