Saturday 9 February 2008

New Scientific Report on Climate Tipping Points View


Above is a photo from August in the Arctic ocean.

Below is a press release from earlier this week on the latest findings from an international group of (real) climate change scientists. I remain pretty convinced that what is being raised is the possibility that things are MUCH worse than we thought, that the damage being done may be accelerating, and that raises the very stark possibility of runaway climate change, and that if that happened it could threaten life on earth to an extent that wasnt previously obvious in the warnings about global warming. Yes it's alarmist to put it this way but what is being described is at worst The End of The World (for human beings and most other species). I'm not saying anyone remotely knows that this is where things are really heading. It's just that personally, if it's a possibility, or within the range of possibilities, as a member of the public I want to know. That's because I weight risk with not only probability but severity. I wouldnt play Russian Roulette and I dont want us to play it with our planet.

I'm not a climate change scientist but I do know a bit about the psychology of mass persuasion and let me tell you, some fresh ALARMISM around this issue is good. Alarmism is good because at long last it leads to sufficient action to make a dent in our heedlessly ignore every warning. My reading of the current mood on sustainability is that after several years of quite promising engagement, a certain amount of complacency was setting in. We need more urgent action, and without for a moment taking our eyes off optimism and energy for solutions, urgency does come from a full realisation of an emergency state. As Al Gore said (Time magazine Dec 07) "The north polar ice cap, according to the best scientists in the world, fell off a cliff this fall. The signs that the world is spinning out of kilter are increasingly difficult to misinterpret. The question is how to convince enough people to join a critical mass of urgent opinion, in the U.S. and the rest of the world... I think we're making progress; it's just that nothing has matched the scale of the response that is truly needed. The unprecedented nature of this crisis does make it difficult to communicate. We naturally tend to confuse the unprecedented with the improbable. But we have become capable of doing catastrophic damage without realizing it."

UEA Press Release 10pm GMT (5pm US Eastern Time) on Monday February 4 2008

'TIPPING POINTS' COULD COME THIS CENTURY

A number of key components of the earth’s climate system could pass their ‘tipping point’ this century, according to new research led by a scientist at the University of East Anglia. Published today by the prestigious international journal Proceedings of the National Academy of Science (PNAS), the researchers have coined a new term, ‘tipping elements’, to describe those components of the climate system that are at risk of passing a tipping point. The term ‘tipping point’ is used to describe a critical threshold at which a small change in human activity can have large, long-term consequences for the Earth’s climate system. In this new research, lead author Prof Tim Lenton of the University of East Anglia (UEA) and colleagues at the Postdam Institute of Climate Impact Research (PIK), Carnegie Mellon University, Newcastle University and Oxford University have drawn up a shortlist of nine tipping elements relevant to current policy-making and calculated where their tipping points could lie. All of them could be tipped within the next 100 years. The nine tipping elements and the time it will take them to undergo a major transition are:
• Melting of Arctic sea-ice (approx 10 years)
• Decay of the Greenland ice sheet (more than 300 years)
• Collapse of the West Antarctic ice sheet (more than 300 years)
• Collapse of the Atlantic thermohaline circulation (approx 100 years)
• Increase in the El Nino Southern Oscillation (approx 100 years)
• Collapse of the Indian summer monsoon (approx 1 year)
• Greening of the Sahara/Sahel and disruption of the West African monsoon
(approx 10 years)
• Dieback of the Amazon rainforest (approx 50 years)
• Dieback of the Boreal Forest (approx 50 years)
The paper also demonstrates how, in principle, early warning systems could be established using real-time monitoring and modelling to detect the proximity of certain tipping points.

“Society must not be lulled into a false sense of security by smooth projections of global change,” said Prof Lenton.

“Our findings suggest that a variety of tipping elements could reach their critical point within this century under human-induced climate change. The greatest threats are tipping of the Arctic sea-ice and the Greenland ice sheet, and at least five other elements could surprise us by exhibiting a nearby tipping point.”

‘Tipping elements in the Earth’s climate system’ by Tim Lenton (UEA and Tyndall Centre), Hermann Held (PIK), Elmar Kriegler (Carnegie Mellon University and PIK), Jim Hall (Newcastle University and Tyndall Centre), Wolfgang Lucht (PIK), Stefan
Rahmstorf (PIK) and Hans Joachim Schellnhuber (PIK, Oxford University and Tyndall Centre) is published by PNAS in the week beginning Monday February 4. The findings are based on a critical review of the literature, the results of a recent workshop held at the British Embassy in Berlin which brought together 36 international experts in the field, and an elicitation exercise involving a further 52 international experts.

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