Countdown to global catastrophe
By Michael McCarthy, Environment Editor
24 January 2005
The global warming danger threshold for the world is clearly marked
for the first time in an international report to be published
tomorrow - and the bad news is, the world has nearly reached it
already.
The countdown to climate-change catastrophe is spelt out by a task
force of senior politicians, business leaders and academics from
around the world - and it is remarkably brief. In as little as 10
years, or even less, their report indicates, the point of no return
with global warming may have been reached.
The report, Meeting The Climate Challenge, is aimed at policymakers
in every country, from national leaders down. It has been timed to
coincide with Tony Blair's promised efforts to advance climate
change policy in 2005 as chairman of both the G8 group of rich
countries and the European Union.
And it breaks new ground by putting a figure - for the first time in
such a high-level document - on the danger point of global warming,
that is, the temperature rise beyond which the world would be
irretrievably committed to disastrous changes. These could include
widespread agricultural failure, water shortages and major droughts,
increased disease, sea-level rise and the death of forests - with
the added possibility of abrupt catastrophic events such
as "runaway" global warming, the melting of the Greenland ice sheet,
or the switching-off of the Gulf Stream.
The report says this point will be two degrees centigrade above the
average world temperature prevailing in 1750 before the industrial
revolution, when human activities - mainly the production of waste
gases such as carbon dioxide (CO2), which retain the sun's heat in
the atmosphere - first started to affect the climate. But it points
out that global average temperature has already risen by 0.8 degrees
since then, with more rises already in the pipeline - so the world
has little more than a single degree of temperature latitude before
the crucial point is reached.
More ominously still, it assesses the concentration of carbon
dioxide in the atmosphere after which the two-degree rise will
become inevitable, and says it will be 400 parts per million by
volume (ppm) of CO2.
The current level is 379ppm, and rising by more than 2ppm annually -
so it is likely that the vital 400ppm threshold will be crossed in
just 10 years' time, or even less (although the two-degree
temperature rise might take longer to come into effect).
"There is an ecological timebomb ticking away," said Stephen Byers,
the former transport secretary, who co-chaired the task force that
produced the report with the US Republican senator Olympia Snowe. It
was assembled by the Institute for Public Policy Research in the UK,
the Centre for American Progress in the US, and The Australia
Institute.The group's chief scientific adviser is Dr Rakendra
Pachauri, chairman of the UN's Intergovernmental Panel on Climate
Change.
The report urges all the G8 countries to agree to generate a quarter
of their electricity from renewable sources by 2025, and to double
their research spending on low-carbon energy technologies by 2010.
It also calls on the G8 to form a climate group with leading
developing nations such as India and China, which have big and
growing CO2 emissions.
"What this underscores is that it's what we invest in now and in the
next 20 years that will deliver a stable climate, not what we do in
the middle of the century or later," said Tom Burke, a former
government adviser on green issues who now advises business.
The report starkly spells out the likely consequences of exceeding
the threshold. "Beyond the 2 degrees C level, the risks to human
societies and ecosystems grow significantly," it says.
"It is likely, for example, that average-temperature increases
larger than this will entail substantial agricultural losses,
greatly increased numbers of people at risk of water shortages, and
widespread adverse health impacts. [They] could also imperil a very
high proportion of the world's coral reefs and cause irreversible
damage to important terrestrial ecosystems, including the Amazon
rainforest."
It goes on: "Above the 2 degrees level, the risks of abrupt,
accelerated, or runaway climate change also increase. The
possibilities include reaching climatic tipping points leading, for
example, to the loss of the West Antarctic and Greenland ice sheets
(which, between them, could raise sea level more than 10 metres over
the space of a few centuries), the shutdown of the thermohaline
ocean circulation (and, with it, the Gulf Stream), and the
transformation of the planet's forests and soils from a net sink of
carbon to a net source of carbon." '
http://news.independent.co.uk/world/environment/story.jsp?story=603975 |