By Bill Henderson
30 September, 2006
big global warming story isn't Americans finally accepting an inconvenient
truth. Al Gore makes a brilliant presentation, but the big story is
the undeniable impact of a severe, early onset, global heating which
only paid deniers now refuse to accept. The emerging science story is
the risk of this severe impact creating positive feedback which could
ratchet up temperatures higher and faster - maybe 10 degrees and more;
within decades, not a century away. The forthcoming fourth IPCC report
will focus upon ' dangerous
Is it possible that the Amazon
might die in a third or fourth year of unprecedented drought? Could
Los Angeles, St.Louis and Atlanta become as hot as Baghdad in the not
too distant future? Could the rapidly melting polar ice sheets raise
sea levels so fast that New York, London, Singapore and every other
coastal city will have to endure New Orleans style inundation? Collapsing
ecosystems, migrating species and disease? A world without polar bears
or tigers and maybe soon without people?
Climate change isn't something
that will happen in the distant future and increasingly it doesn't look
like a gentle warming to which we can adapt.
Newly clear land and sea
in polar regions will absorb more heat from sunlight which would have
been reflected by ice and new science on 'carbon bombs' strongly suggest
that this positive feedback loop is already in operation. The Amazon
is a huge carbon sink that unexpectedly could be freed to become greenhouse
gas. Melting permafrost, especially in Siberia's
yedoma, filling with new lakes, are releasing methane.
Beetles and other parasites normally kept in check by very cold winters
are killing vast areas of heat stressed temperate and boreal forests;
forest fires will help release this carbon into the atmosphere too.
Greenhouse gases from our
burning of fossil fuels trap more heat which in turn melts permafrost
releasing vast amounts of methane which in turn trap more heat raising
temperatures and setting off more carbon bombs - runaway global heating:
Within the next decade
or two, Lovelock forecasts, Gaia will hike her thermostat by at least
10 degrees. Earth, he predicts, will be hotter than at any time since
the Eocene Age 55 million years ago, when crocodiles swam in the Arctic
"There's no realization
of how quickly and irreversibly the planet is changing," Lovelock
says. "Maybe 200 million people will migrate close to the Arctic
and survive this. Even if we took extraordinary steps, it would take
the world 1,000 years to recover."
Lovelock The End of Eden WashPost
The costs today and the range
of potential dangers - including the risk of extinction - from global
heating suggests that the biggest non-story is the complete lack of
informed public debate and the woeful inadequacy of all proposed emission
reduction planning. Kyoto, recent Kyoto-style reduction programs, caps
and trading, alternative energy development - the use of oil and other
fossil fuel use and their contributions of greenhouse gases continue
their relentless rise uneffected. Critical decades have been wasted.
The problem of path dependence and resulting policy paralysis isn't
even a lesson yet learned by climate change experts.
A Draconian change of paths
is now clearly necessary and yet impossible. While now accepting human
caused global warming, the public still perceives the danger as a moderate
increase in temperature requiring shallow, blue box and biking style
"Further global warming
of 1 °C defines a critical threshold. Beyond that we will likely
see changes that make Earth a different planet than the one we know."
Earth is already as warm
as at any time in the last 10,000 years, and is within 1 °C of being
its hottest for a million years, says Hansen's team. Another decade
of business-as-usual carbon emissions will probably make it too late
to prevent the ecosystems of the north from triggering runaway climate
change, the study concludes (Proceedings of the National Academy of
Sciences, vol 103, p 14288).
Pearce New Scientist
On This Article