[IPSM] World on course for catastrophic 6°C rise, reveal scientists

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http://www.independent.co.uk/environment/climate-change/world-on-course-for-catastrophic-6deg-rise-reveal-scientists-1822396.html


World on course for catastrophic 6° rise, reveal scientists

Fast-rising carbon emissions mean that worst-case predictions for 
climate change are coming true

By Steve Connor and Michael McCarthy

Wednesday, 18 November 2009



The world is now firmly on course for the worst-case scenario in terms 
of climate
change, with average global temperatures rising by up to 6C by the end 
of the
century, leading scientists said yesterday. Such a rise – which would be 
much
higher nearer the poles – would have cataclysmic and irreversible 
consequences
for the Earth, making large parts of the planet uninhabitable and 
threatening the
basis of human civilisation.

We are headed for it, the scientists said, because the carbon dioxide 
emissions
from industry, transport and deforestation which are responsible for 
warming the
atmosphere have increased dramatically since 2002, in a way which no one
anticipated, and are now running at treble the annual rate of the 1990s.

This means that the most extreme scenario envisaged in the last report 
from the
UN Intergovernmental Panel on Climate Change, published in 2007, is now the
one for which society is set, according to the 31 researchers from seven 
countries
involved in the Global Carbon Project.
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Although the 6C rise and its potential disastrous effects have been 
speculated
upon before, this is the first time that scientists have said that 
society is now on
a path to meet it.

Their chilling and remarkable prediction throws into sharp relief the 
importance of
next month's UN climate conference in Copenhagen, where the world community
will come together to try to construct a new agreement to bring the 
warming under
control.

For the past month there has been a lowering of expectations about the 
conference,
not least because the US may not be ready to commit itself to cuts in 
its emissions.
But yesterday President Barack Obama and President Hu Jintao of China 
issued a
joint communiqué after a meeting in Beijing, which reignited hopes that 
a serious
deal might be possible after all.

It cannot come too soon, to judge by the results of the Global Carbon 
Project study,
led by Professor Corinne Le Quéré, of the University of East Anglia and 
the British
Antarctic Survey, which found that there has been a 29 per cent increase 
in global
CO2 emissions from fossil fuel between 2000 and 2008, the last year for 
which
figures are available.

On average, the researchers found, there was an annual increase in 
emissions of
just over 3 per cent during the period, compared with an annual increase 
of 1 per cent
between 1990 and 2000. Almost all of the increase this decade occurred 
after 2000
and resulted from the boom in the Chinese economy. The researchers predict a
small decrease this year due to the recession, but further increases 
from 2010.

In total, CO2 emissions from the burning of fossil fuels have increased 
by 41 per cent
between 1990 and 2008, yet global emissions in 1990 are the reference 
level set
by the Kyoto Protocol, which countries are trying to fall below in terms 
of their own
emissions.

The 6C rise now being anticipated is in stark contrast to the C rise at 
which all
international climate policy, including that of Britain and the EU, 
hopes to stabilise
the warming – two degrees being seen as the threshold of climate change 
which is
dangerous for society and the natural world.

The study by Professor Le Quéré and her team, published in the journal 
Nature
Geoscience, envisages a far higher figure. "We're at the top end of the IPCC
scenario," she said.

Professor Le Quéré said that Copenhagen was the last chance of coming to a
global agreement that would curb carbon-dioxide emissions on a time-course
that would hopefully stabilise temperature rises to within the danger 
threshold.
"The Copenhagen conference next month is in my opinion the last chance to
stabilise climate at C above pre-industrial levels in a smooth and 
organised way,"
she said.

"If the agreement is too weak, or the commitments not respected, it is 
not 2.5C
or 3C we will get: it's 5C or 6C – that is the path we're on. The 
timescales here
are extremely tight for what is needed to stabilise the climate at C," 
she said.

Meanwhile, the scientists have for the first time detected a failure of 
the Earth's
natural ability to absorb man-made carbon dioxide released into the air.

They found significant evidence that more man-made CO2 is staying in the
atmosphere to exacerbate the greenhouse effect because the natural "carbon
sinks" that have absorbed it over previous decades on land and sea are 
beginning
to fail, possibly as a result of rising global temperatures.

The amount of CO2 that has remained in the atmosphere as a result has
increased from about 40 per cent in 1990 to 45 per cent in 2008. This 
suggests
that the sinks are beginning to fail, they said.

Professor Le Quéré emphasised that there are still many uncertainties 
over carbon
sinks, such as the ability of the oceans to absorb dissolved CO2, but 
all the
evidence suggests that there is now a cycle of "positive feedbacks", whereby
rising carbon dioxide emissions are leading to rising temperatures and a
corresponding rise in carbon dioxide in the atmosphere.

"Our understanding at the moment in the computer models we have used – and
they are state of the art – suggests that carbon-cycle climate feedback 
has already
kicked in," she said.

"These models, if you project them on into the century, show quite large 
feedbacks,
with climate amplifying global warming by between 5 per cent and 30 per 
cent.
There are still large uncertainties, but this is carbon-cycle climate 
feedback that
has already started," she said.

The study also found that, for the first time since the 1960s, the 
burning of coal
has overtaken the burning of oil as the major source of carbon-dioxide 
emissions
produced by fossil fuels.

Much of this coal was burned by China in producing goods sold to the West –
the scientists estimate that 45 per cent of Chinese emissions resulted from
making products traded overseas.

It is clear that China, having overtaken the US as the world's biggest 
carbon
emitter, must be central to any new climate deal, and so the communiqué from
the Chinese and US leaders issued yesterday was widely seized on as a sign
that progress may be possible in the Danish capital next month.

Presidents Hu and Obama specifically said an accord should include
emission-reduction targets for rich nations, and a declaration of action 
plans
to ease greenhouse-gas emissions in developing countries – key elements in
any deal.

6C rise: The consequences

If two degrees is generally accepted as the threshold of dangerous 
climate change,
it is clear that a rise of six degrees in global average temperatures 
must be very
dangerous indeed, writes Michael McCarthy. Just how dangerous was signalled
in 2007 by the science writer Mark Lynas, who combed all the available 
scientific
research to construct a picture of a world with temperatures three times 
higher
than the danger limit.

His verdict was that a rise in temperatures of this magnitude "would 
catapult the
planet into an extreme greenhouse state not seen for nearly 100 million 
years,
when dinosaurs grazed on polar rainforests and deserts reached into the 
heart
of Europe".

He said: "It would cause a mass extinction of almost all life and 
probably reduce
humanity to a few struggling groups of embattled survivors clinging to 
life near
the poles."

Very few species could adapt in time to the abruptness of the transition, he
suggested. "With the tropics too hot to grow crops, and the sub-tropics 
too dry,
billions of people would find themselves in areas of the planet which are
essentially uninhabitable. This would probably even include southern Europe,
as the Sahara desert crosses the Mediterranean.

"As the ice-caps melt, hundreds of millions will also be forced to move 
inland
due to rapidly-rising seas. As world food supplies crash, the higher 
mid-latitude
and sub-polar regions would become fiercely-contested refuges.

"The British Isles, indeed, might become one of the most desirable pieces of
real estate on the planet. But, with a couple of billion people knocking 
on our
door, things might quickly turn rather ugly."