Newsgroup: it.politica.internazionale
Titolo: Siamo tutti fottuti?

Forse e' la volta (non) buona.
Altro che Iraq e Palestina.
Forse ci siamo fumati il mondo.  Letteralmente.
http://www.commondreams.org/headlines04/1011-01.htm
Climate Fear as Carbon Levels Soar
Scientists bewildered by sharp rise of CO2 in atmosphere for second
year running
by Paul Brown
 
An unexplained and unprecedented rise in carbon dioxide in the
atmosphere two years running has raised fears that the world may be on
the brink of runaway global warming.
Scientists are baffled why the quantity of the main greenhouse gas has
leapt in a two-year period and are concerned that the Earth's natural
systems are no longer able to absorb as much as in the past.
The findings will be discussed tomorrow by the government's chief
scientist, Dr David King, at the annual Greenpeace business lecture.
Measurements of CO2 in the atmosphere have been continuous for almost
50 years at Mauna Loa Observatory, 12,000ft up a mountain in Hawaii,
regarded as far enough away from any carbon dioxide source to be a
reliable measuring point.
In recent decades CO2 increased on average by 1.5 parts per million
(ppm) a year because of the amount of oil, coal and gas burnt, but has
now jumped to more than 2 ppm in 2002 and 2003.
Above or below average rises in CO2 levels in the atmosphere have been
explained in the past by natural events.
When the Pacific warms up during El Niño - a disruptive weather
pattern caused by weakening trade winds - the amount of carbon dioxide
rises dramatically because warm oceans emit CO2 rather than absorb it.
But scientists are puzzled because over the past two years, when the
increases have been 2.08 ppm and 2.54 ppm respectively, there has been
no El Niño.
Charles Keeling, the man who began the observations in 1958 as a young
climate scientist, is now 74 and still working in the field.
He said yesterday: "The rise in the annual rate to above two parts per
million for two consecutive years is a real phenomenon.
"It is possible that this is merely a reflection of natural events
like previous peaks in the rate, but it is also possible that it is
the beginning of a natural process unprecedented in the record."
Analysts stress that it is too early to draw any long-term
conclusions.
But the fear held by some scientists is that the greater than normal
rises in C02 emissions mean that instead of decades to bring global
warming under control we may have only a few years. At worst, the
figures could be the first sign of the breakdown in the Earth's
natural systems for absorbing the gas.
That would herald the so-called "runaway greenhouse effect", where the
planet's soaring temperature becomes impossible to contain. As the
icecaps melt, less sunlight is reflected back into space from ice and
snow, and bare rocks begin to absorb more heat. This is already
happening.
One of the predictions made by climate scientists in the
Intergovernmental Panel on Climate Change is that as the Earth warms,
the absorption of carbon dioxide by vegetation - known as "carbon
sink" - is reduced.
Dr Keeling said since there was no sign of a dramatic increase in the
amount of fossil fuels being burnt in 2002 and 2003, the rise "could
be a weakening of the Earth's carbon sinks, associated with the world
warming, as part of a climate change feedback mechanism. It is a cause
for concern'.'
Tom Burke, visiting professor at Imperial College London, and a former
special adviser to the former Tory environment minister John Gummer,
warned: "We're watching the clock and the clock is beginning to tick
faster, like it seems to before a bomb goes off."
Peter Cox, head of the Carbon Cycle Group at the Met Office's Hadley
Center for Climate Change, said the increase in carbon dioxide was not
uniform across the globe.
Measurements of CO2 levels in Australia and at the south pole were
slightly lower, he said, so it looked as though something unusual had
occurred in the northern hemisphere.
"My guess is that there were extra forest fires in the northern
hemisphere, and particularly a very hot summer in Europe," Dr Cox
said. "This led to a die-back in vegetation and an increase in release
of carbon from the soil, rather than more growing plants taking carbon
out of the atmosphere, which is usually the case in summer."
Scientists are have dubbed the two-year CO2 rise the Mauna Loa
anomaly. Dr Cox said one of its most interesting aspects was that the
CO2 rises did not take place in El Niño years. Previously the only
figures that climbed higher than 2 ppm were El Niño years - 1973,
1988, 1994 and 1998.
The heatwave of last year that is now believed to have claimed at
least 30,000 lives across the world was so out of the ordinary that
many scientists believe it could only have been caused by global
warming.
But Dr Cox, like other scientists, is concerned that too much might be
read into two years' figures. "Five or six years on the trot would be
very difficult to explain," he said.
Dr Piers Forster, senior research fellow of the University of
Reading's Department of Meteorology, said: "If this is a rate change,
of course it will be very significant. It will be of enormous concern,
because it will imply that all our global warming predictions for the
next hundred years or so will have to be redone."
David J Hofmann of the US National Oceanic and Atmospheric
Administration centre, which also studies CO2, was more cautious.
"I don't think an increase of 2 ppm for two years in a row is highly
significant - there are climatic perturbations that can make this
occur," he said. "But the absence of a known climatic event does make
these years unusual.
"Based on those two years alone I would say it was too soon to say
that a new trend has been established, but it warrants close
scrutiny."
© Guardian Newspapers Limited 200

 Forse ci siamo fumati il mondo.  Letteralmente.
L'ho sempre detto: nucleare ueber alles.