By Michael McCarthy
24 January 2005
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.
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."