While the press release says University of Exeter, this slide show by Tim Lenton from the University that brought up ClimateGate, UEA, sees tipping worry in every event.
Source: http://www.slideshare.net/Stepscentre/tim-lenton-early-warning-of-climate-tipping-points
From Eurekalert:
Climate change disasters could be predicted
Climate change disasters, such as the melting of the Greenland ice sheet, dieback of the Amazon rainforest or collapse of the Atlantic overturning circulation, could be predicted according to University of Exeter research.
Writing in the journal Nature Climate Change, Professor Tim Lenton of the University of Exeter shows that the ‘tipping points’ that trigger these disasters could be anticipated by looking for changes in climate behaviour.
Climate ‘tipping points’ are small changes that trigger a massive shift in climate systems, with potentially devastating consequences. It is already known that climate change caused by human activity could push several potential hazards past their ‘tipping point’. However, it is often assumed that these ‘tipping points’ are entirely unpredictable.
Professor Lenton argues that a system of forecasting could be developed to enable some forewarning of high-risk tipping points. The approach he outlines involves analysing observational data to look for signs that a climate system is slowing down in its response to short-term natural variability (which we experience as the weather). This characteristic behaviour indicates the climate is becoming unstable, and is a common feature of systems approaching critical thresholds known as ‘bifurcation points’.
Professor Tim Lenton of the University of Exeter said: “Many people assume that tipping points which could be passed as a result of human-induced climate change are essentially unpredictable. Recent research shows that the situation is not as hopeless as it may seem: we have the tools to anticipate thresholds, which means we could give societies valuable time to adapt.
“Although these findings give us hope, we are still a long way from developing rigorous early warning systems for these climate hazards.”
Early warning of climate tipping points by Professor Timothy Lenton (University of Exeter) is published in Nature Climate Change volume 1, issue 3, July 2011 and online on Sunday 19 June at 18.00 BST. Copies available on request.
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Here is the transcript for the slide show above.
Tim Lenton – Early warning of climate tipping points – Presentation Transcript
- Early warning of climate tipping points Tim Lenton School of Environmental Sciences, University of East Anglia, Norwich With special thanks to Valerie Livina, John Schellnhuber, Frank Kwasniok
- Outline Tipping elements Risk assessment Early warning
- Two types of tipping point Bifurcation
- Two types of tipping point Bifurcation No bifurcation
- Policy relevant forcing range IPCC (2007) = High growth = Mid growth = Low growth
- Tipping elements in the climate system Revised from original in Lenton et al. (2008) PNAS 105(6): 1786-1793 October 11, 2010
- Estimates of proximity Lenton & Schellnhuber (2007) Nature Reports Climate Change Results from literature review and workshop
- Likelihood of tipping Kriegler et al. (2009) PNAS 10.1073/pnas.0809117106 Imprecise probability statements from experts Atlantic formally combined Under 2-4 °C warming: Greenland >16% probability of passing at least one of five tipping points Antarctica Under >4 °C warming: >56% probability of passing at least one of Amazon five tipping points El Niño
- Impacts of tipping Lenton, Footitt & Dlugolecki (2009) http://assets.panda.org/downloads/plugin_tp_final_report.pdf Populations exposed to 1-in-100-yr flood events Allianz / WWF report: Increased sea level rise +$25,158 billion exposed assets in port megacities Indian summer monsoon disruption Amazon dieback and drought Aridification of southwest North America October 11, 2010
- Tipping element risk assessment Tipping element Likelihood of Relative Risk score Risk ranking passing a tipping impact** of (likelihood x point change in state impact) (by 2100) (by 3000) Arctic summer sea-ice High Low 3 4 Greenland ice sheet Medium-High* High 7.5 1 (highest) West Antarctic ice sheet Medium* High 6 2 Atlantic THC Low* Medium-High 2.5 6 ENSO Low* Medium-High 2.5 6 West African monsoon Low High 3 4 Amazon rainforest Medium* Medium 4 3 Boreal forest Low Low-Medium 1.5 8 (lowest) *Likelihoods informed by expert elicitation **Initial judgment of relative impacts is my subjective assessment Impacts depend on human responses hence are more epistemologically contested than assigning likelihoods to events (Stirling 2003 ‘Risk, uncertainty and precaution…’) October 11, 2010
- Prospects for bifurcation early warning Held & Kleinen (2004) Geophysical Research Letters 31: L23207 Lenton et al. (2008) PNAS 105(6): 1786-1793 Generic early warning signals: Slowing down Increasing variability Skewness of responses Flickering between states System being forced past a tipping point October 11, 2010
- Model test of early warning method Held & Kleinen (2004) Geophysical Research Letters 31: L23207 CLIMBER-2 intermediate complexity model Linear increase in CO2 from 280 to 800 ppmv Stochastic perturbation of freshwater forcing
- Fully 3-D dynamical model test Lenton et al. (2009) Phil. Trans. A 367: 871-884 Atlantic meridional overturning circulation Early warning indicator from autocorrelation function Early warning indicator from detrended fluctuation analysis October 11, 2010 GENIE-2 model
- Paleo-data test of early warning method Livina & Lenton (2007) Geophysical Research Letters 34: L03712 Greenland ice-core regional temperature record Early warning indicator from detrended fluctuation analysis Early warning indicator from autocorrelation function October 11, 2010
- Detecting the number of system states Livina, Kwasniok & Lenton (2010) Climate of the Past, 6: 77-82 New method; „potential analysis‟: Assume polynomial potential and random noise Estimate number of states (i.e. order of polynomial) Estimate noise level Derive potential coefficients and hence shape of potential Number of states: 1, 2, 3, 4 October 11, 2010
- Changing number of climate states Livina, Kwasniok & Lenton (2010) Climate of the Past, 6: 77-82 Number of states: 1, 2, 3, 4
- European monthly temperature anomaly (1659-2004) Livina et al. (in revision) Climate Dynamics Number of states: 1, 2, 3, 4 October 11, 2010
- Atlantic Multi-decadal Oscillation (1856-present) Livina et al. (in revision) Climate Dynamics Number of states: 1, 2, 3, 4
- Conclusion Tipping elements in the climate system could be triggered this century by anthropogenic forcing The Greenland and West Antarctic ice sheets probably represent the largest risks Some tipping points can be anticipated in principle, but sufficiently high-resolution, long records are often lacking A change in the number of climate states can be detected, in a noisy climate system that is moving between states Improved understanding is needed to help policy makers “avoid the unmanageable and manage the unavoidable” October 11, 2010
- Find out more http://knowledge.allianz.com/climate_tipping_points/climate_en.html October 11, 2010
- Example of transition (but not bifurcation) Livina, Ditlevsen, Lenton (submitted) Nonlinear Processes in Geophysics Sigmoid function with red noise, fluctuation exponent 0.7 ACF-propagator (without detrending) is more sensitive to transitions
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I’ve yet to see a “climate change disaster”. I would suppose that the closest thing that qualifies would be the Vikings getting frozen out of Greenland as the MWP ended. Lenton’s study assumes that Earth’s climate will become more chaotic due to AGW, rather than establishing some new equilibrium point.
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The greening of the Sahara signals a climate tipping point?
“…From about 9000 B.C. to 2500 B.C., the Sahara had a much wetter climate during the Neolithic period which was quite habitable for humans and animals, similar to the savannah of East Africa today…”
http://www.suite101.com/content/prehistoric-saharan-rock-art-a185287
Of course, like the Viking settlements of Southern Greenland c 900 – c 1300 AD, that period of a ‘Green Sahara’ was purely a local phenomenon (ahem) and anyway was not due to “human induced climate change” and therefore was never likely to be “dangerous”.
The mathematically abstract offers infinite possibilities which are irresistible to those disconnected from reality.
Lots of fun to be had by these numerous adventurous folks on an infinity of red herring chases. The aspect of nature that most fascinates the group is the creative potential of human imagination.
Art? Or science?
Anthony said:
I’ve yet to see a “climate change disaster”.
Could a global plague epidemic be regarded as a “climate change disaster”? They usually (historically) occured during the cold times (starting with Justinian’s Plague during the Dark Ages—6th Century—and the various Black Death bubonic plagues which swept through Europe after the MWP—14th Century etc).
Tipping is for the wait staff. The Tipping Point is usually about 15% when alone, 20% with my wife. If some one is playing the accordian we don’t tip at all.
And they want how much money to do this?
i cant wait to see what horrible climate disaster awaits us because of the Sahara becoming more green…!!
Exeter University, UEA, Reading University, Tyndall Centre, MET Ofice. They are all linked together as part of the climate change disaster propaganda tool. There are no proper scientists in any of them.
It might be this, it might be that, then again, it might be worse than we thought? We think we know the signs but we are worried about the “tipping point” when the tea cup is inverted and the leaves fall out!!
I shudder to think what sort of “fix” might be dreamed up if these fruitcake mixers are let loose on the world – Alkaline solutions dumped in the oceans, black soot spread over ice, pavements painted white, volcanoes induced to erupt, disruption of atmospheric layers, seeding upper atmosphere with silver sprinkles, towable clouds and ice bergs, magnetic disruption, atomic concussion to shift the axis of the earth or merely killing off all the old sick and poor to appease the climate gods and what do they do when the run out of witches!!!
Akin to drawing ducks on a Climental cell wall with charcoal and “believing” the ducks will eat and be happy when a crumb is tossed to them. Mutual madness as an end result of “oofall bird” science perhaps.
Best tipping point, would be to tip them all out of a job and start again.
THC shutdown was predicted s few years ago. A tipping point caused by freshwater influx in the North Atlantic that would, ironically, cause NW Europe to become much colder – so the AGW catastrophe theory was shown to not cause uniform warming.
That one had lots of gullible people running around in circles, worrying.
Now quietly forgotten.
“Although these findings give us hope, we are still a long way from developing rigorous early warning systems for these climate hazards.”
or…
Although these “findings” give us hope, we are now asking for much more money to develop this and that to be ever more wild in our assumptions about climate in the far future.
So many tipping points actually makes it rather balanced. Or maybe Mayan.
Are we approaching the CO2 levels that make Earth more vulnerable to a rogue black hole yet?
How high can the parabolic wolf-crying hockey stick go before it snaps?
The bifurcation of the global climate is very interesting as it shows how different climates on earth can not be added up to make an actual estimate of temperature.
Where I live we have a climate that has been gradually cooling over the past 4+ years for a fact, but if figures were added to the average temperatures from warmer climates to temperatures from my part of the world then temperatures here would be diluted to the point where the bifurcation of that data is utterly useless.
It seems we can now deal out recorded global temperatures and geographically assign an artificial climate based on the break down of where we think the morphed statistical average temperatures should, this is a break through in science!! Wow!
What you have to realise is that the CRU at the University of East Anglia lies perilously close to sea level. For those who have never been there it lies in a region of the UK which resembles in terrain (but sadly not attractiveness) its near neighbour over the North Sea – Holland. So, its interest in climate shifts, rising sea levels and its own potential inundation is not driven by large sums of money from multiple benefactors but out of a desperate desire to remain afloat. What is definitely true is that the university would have been swept away except for the large sums of ‘research’ funding flowing into the CRU. The university lies around about 28th in the UK league table and in the global rankings doesn’t even rate an honourable mention. It’s other research income is rather pitiful and would be insufficient to kit out the vice chancellors office with emergency snorkels. So you see the denizens of the CRU have their fingers in the UEA’s financial dyke and their preservation is the university’s top priority. I think it is only reasonable to point these issues out so that you all understand the damage that attacks on this beacon of intellectual excellence might bring about.
University of Environmental Alarmism
The Greenland and West Antarctic ice sheets probably represent the largest risks
Seriously? The HUGE mass of ice represented in those two places is teetering on the edge, to melt in a flash, with no chance of reforming? I call BS on that.
Nor can forest die back have a tipping point. If forests retreat a bit they can grow back again if conditions revert. The Amazonian rain forest is not actually very ancient anyway, despite what the Greenies would have you believe. It was savannah over much of its current extent only 21,000 years ago. So much for that “tipping point”.
I don’t think he knows what a tipping point is actually. He’s using a buzz-word and hoping no-one notices.
It’s the Sahel that is greening, not the Sahara.
He left out the mountainous columns of super-heated steam and gas blasting out of the string of BS volcanoes named after certain universities; e.g. PSU, UEA and Exeter.
Tim Lenton’s Early Warning of Climate Tipping Points is short on evidence,
‘..tipping points can be predicted in principle but sufficiently high resolution long records are often lacking.’
but is itself part of a long, historical,( sometimes hysterical? ) tradition of doomsday predictions.
Early Christian texts like The Revelation of St John the Divine, claimed an early end to the World. WRONG.
In the 1520s translations of the Jewish Talmud of Babylon included the Prophecy of Elias that the world would end around the year 2000. At this point in time, WRONG.
Malthus in the 18th century,Ehrlich among others, in the twentieth century, predicted disastrous global famine brought on by overpopulation. INCORRECT.
In the 1970s The Club of Rome published a powerful tract based on modelling by the new computer technology to predict catastrophe in the 21st century from over population and development. About ot go into its 12th reprint, it was found to contain significantly erronious statistics. SOUND FAMILIAR?
Every Millenium has had its disaster prophecies. Professor Geoffrey Blainey, economic historian, in his book, “The Great Seesaw,” examines the swings of optimism and pessimism in western history that have been shaped by political and economic events but also by subjective factors, primarily, our lack of collective memory, ‘a feeble and imperfect knowledge of the past and its relevance to the present.’
Nice one! And all too accurate.
Some of those tipping-points are actually very desirable, like greening of sahara and deicing of arctics
yes, and also there is no reason why forests must die back – all the paleodata tells us is that forests are much better off in warmer climates, especially mid-latitude forests. Boreal forests may retreat northward, replacing tundra and permafrost, but that is also a good thing!
let’s face it, homo sapiens sapiens are a mix of biophiles and necrophiles, and i prefer sharing my time with the biophiles on WUWT and other sceptic sites. best wishes everyone.
It is already known that climate change caused by human activity could push several potential hazards past their ‘tipping point’. Oh really???
And the band played “believe it if you like”, as my dear old mother used to say!
Can we go the whole hog and include:-
Robots taking over world
Asteroid colliding with Earth
Comet colliding with Earth
Terrorists releasing superbug
Nuclear armageddon
Aliens taking over world
Zombies taking over world
The Rapture
Vampire invasion
Return of bubonic plague
Mega-tsunami caused by Canary Islands dropping into ocean
Mega-volcano caused by Yellowstone park exploding
Mike Jonas says:
June 19, 2011 at 10:21 pm
OK, OK, et’s suppose that this is science, in which case it can be tested: All Tim Lenton has to do is to apply his hypothesis to make some specific predictions – fully documented of course. We can then all check to see if he was right.
Good luck with that. If I read it right, bullet point 10 appears to move the target date to the year 3000 … nicely in the future with no danger of falsifiability within anyone’s lifetime.