[Texgreen] Global warming is speeding up

[Roger Baker]

[The feedback loops seem to be going positive, much as British =20
scientist James Lovelock has predicted. -- Roger]


<http://www.ipsnews.net/news.asp?idnews=3D39824>

CLIMATE CHANGE:  CO2 Levels Begin Accelerated Climb
By Stephen Leahy

BROOKLIN, Canada, Oct 26 (IPS) - Global warming has been compared to =20
a slow-moving train wreck, in which the passengers are blissfully =20
unaware of the coming catastrophe.

With the shocking loss of the Arctic sea ice this summer and several =20
new reports this week that oceans and tropical forests are now =20
absorbing less of the world's steadily rising carbon emissions, our =20
collective train wreck appears to have already tipped into fast forward.

"Global warming is a big feature of our lives now. It is no longer =20
something that only future generations will have to cope with," said =20
Ted Scambos, senior research scientist at the National Snow and Ice =20
Data Centre in the U.S. city of Boulder, Colorado.

The major ecosystems that absorb carbon emissions from the atmosphere =20=

are failing, and it is happening faster than anticipated, Scambos =20
told IPS.

The concentration of carbon dioxide (CO2) in the atmosphere is =20
increasing much more rapidly than even the surging economic growth of =20=

China and India and the global economy can account for. The reason is =20=

a decline in the efficiency of emissions-absorbing "carbon sinks" on =20
land and in the oceans, researchers reported this week in the =20
Proceedings of the National Academy of Science.

About half of the CO2 emissions resulting from human activities are =20
absorbed by natural "sinks", such as forests, other vegetation and =20
the oceans, but this new study shows that the efficiency of these =20
sinks has fallen significantly over the past half century.

Corinne Le Qu=E9r=E9, a climate researcher at the British Antarctic =20
Survey, told IPS last May that stronger winds in the Southern Ocean =20
caused by global warming have resulted in it absorbing less and less =20
carbon since 1981. Those winds churn the ocean waters, bringing up =20
more dissolved carbon dioxide from the deep sea to the surface, and =20
consequently less carbon dioxide is absorbed from the atmosphere.

The process is also making the oceans more acidic, threatening coral =20
and other marine life.

"We are depending on carbon sinks like the oceans to absorb a huge =20
amount of our emissions," Le Qu=E9r=E9 said. "This means there is more =20=

urgency than ever to reduce our emissions."

Oceans are also warming, which also reduces their ability to absorb =20
carbon, said Scambos. Warmer North Pacific water is flowing into the =20
Arctic Ocean and is one of the main reasons behind this summer's =20
startling loss of summer sea ice in the Arctic. For the first time in =20=

human memory, the fabled Northwest Passage from the Atlantic to the =20
Pacific Ocean was ice-free.

While Arctic sea ice retreats temporarily every summer, this summer =20
the retreat was 2.6 million square kilometres larger than any =20
previous summer's loss..

The big meltdown was outside the range of previous scientific =20
projections, and even worst-case scenarios, said Scambos. It likely =20
represents a new era of accelerated warming over the next few =20
decades, he said. This acceleration may well mean that the Arctic =20
could be completely ice-free in 10 years -- decades faster than =20
previous predications made only a year ago.

Hotter oceans are also statistically correlated with four of the five =20=

major extinctions in the past 520 million years of Earth's history, =20
according to a study published Wednesday in the Proceedings of the =20
Royal Society B, a British journal focusing on biological sciences.

Earth is on track to hit this extinction-triggering warming point in =20
about 100 years unless greenhouse gas emissions are curbed, predicts =20
Peter Mayhew of the University of York in Britain.

Another tipping point may have already been reached as warming =20
temperatures appear to have reduced tropical forests' ability to =20
absorb carbon, says a series of new studies published Thursday in the =20=

New Scientist magazine. Across the world, from the Amazon rainforest =20
to the Indonesian archipelago, tree growth is slowing down. Rising =20
temperatures, especially at night, have long been predicted to affect =20=

forest growth, but no one thought it would begin to affect forests =20
until after global temperatures had risen another 1.5 degrees C.

"It would be terribly worrying if that feedback is already kicking =20
in," said climatologist Rachel Warren from the University of East =20
Anglia in Britain.

The world's tropical forests are estimated to absorb some 15 percent =20
of the carbon that humans are emitting and are considered vital in =20
avoiding catastrophic climate change.

It is not just temperatures that are rising -- plants must also live =20
with higher levels CO2 levels. Scientists at the Smithsonian Tropical =20=

Research Institute in Panama have reported faster growing trees, =20
while liana vines have spread 50 to 100 percent in the past 20 years =20
in the Amazon. Unfortunately, these plants absorb much less carbon =20
than the slower growing tropical hardwoods and also kill such trees =20
prematurely. The net effect is that forests will store less carbon, =20
leaving more in the atmosphere, they conclude. Ocean and forest =20
carbon sequestration are crucial factors in climate models. This new =20
revelation that less carbon is being trapped means global average =20
temperatures are going to rise faster and will likely be at the high =20
end of predictions by the Intergovernmental Panel on Climate Change =20
(IPCC) of 2 to 4.5 degrees C for doubling of CO2.

The higher end of this range is not only the most risky, it is the =20
most unpredictable. Once the world comes close to a 4-degree C rise, =20
conditions on the planet will be so different it is nearly impossible =20=

to predict when the warming will stop and what impacts it will have, =20
write Myles Allen and David Frame of Oxford University in the Oct. 26 =20=

issue of Science magazine.

The main lesson from all this is that policy-makers will not get any =20
better information on how warm it could get, they write.

"With less carbon being captured by the oceans and forests, the =20
future doesn't look good," said Scambos.

The only hope now is major declines in emissions. If millions of =20
people really push for major cuts in emissions, change could happen =20
very fast, he said.

"My biggest worry is that by not acting soon enough, we won't have =20
the resources to do more than keep our heads above water," Scambos =20
concluded.

(END/2007)=20=