marklynas.orgThe climate change clock is ticking 01 August 08
The exact timescale of global warming is unknown, but the 100 months campaign provides a much-needed sense of urgency
The UK is in denial about its real carbon emissions, suggests a report from the Stockholm Environment Institute. The academics conclude that if “outsourced” emissions produced in countries like China on goods which are imported into the UK are included in our total carbon footprint, this country’s total greenhouse gas emissions are 49% higher than currently reported. So we should think twice when blaming the Chinese for emitting the CO2 that is required in the manufacture of our fridges and televisions.
The report illustrates once again – as if we had forgotten – that global warming is an, er, global issue. A tonne of CO2 is a tonne of CO2, wherever it is emitted. How you do the counting is more a matter of politics than mathematics. A much greater concern is that all the politics is in danger of obscuring the increasingly drastic nature of the climate change threat. According to Andrew Simms of the New Economics Foundation, the world has only got 100 months left if we are to have a reasonably high chance of staving off runaway global warming.
This is a pretty dramatic claim, and the associated onehundredmonths.org website has an equally dramatic ticking clock counting down until runaway warming begins. “When the clock stops ticking,” it states ominously, “we’ll be beyond the climate’s tipping point, the point of no return.” Yikes. So how valid is this claim? Luckily, NEF’s website provides a 100 Months technical note (pdf) explaining the calculations behind the new campaign. The first thing I noticed is that there isn’t any new modelling work underlying the claim: it is based on existing science, in particular on an analysis by a researcher called Malte Meinshausen which was published in 2006.
Meinshausen was the first scientist to quantify with percentage figures the probability of exceeding certain climatic thresholds: in his 2006 paper he concluded that only by stabilising greenhouse gas concentrations in the atmosphere at 400 part per million (ppm) would it be “likely” (defined as 66-90% chance) that the world would stay below an eventual warming of two degrees. The NEF analysis has performed a fairly simple calculation, simply counting the time left before this 400ppm level is reached. The deadline, it turns out, is 1 December 2016.
There are several complicating factors, however. The 400ppm figure in question is not for CO2 only, but for a basket of atmosphere-altering gases – some of which have a positive “forcing” effect (like CO2 itself) whereas others have a negative (cooling) effect, like sulphate aerosols released by industry. Add the sum of these forcings together and you can arrive at a “CO2-equivalence” figure, which is the one that both NEF and Meinshausen use. The timescales need to be borne in mind, however: CO2 resides in the atmosphere for a century on average, whereas aerosols are washed out by rain in just a week or so.
There are other caveats too. Meinshausen is not saying that two degrees of warming will be reached with certainty when we cross the 400ppm threshold, but that the risk of seeing two degrees increases steadily thereafter. (Even at 400ppm there is still a risk of overshooting 2C, of somewhere between 2% and 57%.) At 450ppm the risk of crossing the 2C line rises to between 26 and 78%, whereas at 550ppm the risk of overshooting is between 68 and 99%. Indeed, for 550ppm the risk of overshooting even 3C ranges from 21% to 69%.
All we can say with near-certainty is that the warmer it gets, the further into dangerous territory we stray
So what do all these numbers mean? Reading the small print, sceptics might complain about the false precision implied by the 100 months clock, which seems to suggest that the minute, indeed the second, we pass 400ppm we are certain to see two degrees of warming. The truth is that no one knows where any of the relevant climatic tipping points – from the disappearance of the Arctic ice cap to the release of methane from melting permafrost – actually lie. There are uncertainties regarding both what level of carbon emissions equals what temperature rise, and what temperature rise equals which climatic impacts. All we can say with near-certainty is that the warmer it gets, the further into dangerous territory we stray.
And again, there is the question of timescales. Meinshausen’s two degrees calculations referred to two degrees of warming, not the minute the 400ppm line is crossed in December 2016, but when the atmosphere reaches “equilibrium” – in other words when all the warming processes have had a chance to feed through the system. Like a boiling kettle, the planet has a substantial thermal timelag – it takes a long time for ice sheets to rebalance themselves and for warmer waters to penetrate to the bottom of the deepest oceans. So even at this “tipping point” we still wouldn’t see the expected two degrees of warming until the end of the century at least, if today’s climate models are to be believed.
Reassuring, perhaps – but no cause for complacency. The earth’s thermal timelag also means that today’s emissions will keep on causing warming for decades to come, and that decisions made today on emissions cuts are essential if we are to rebalance the climate in the second half of the century.
The great danger of climate change is that it is a long-term systemic process. Self-evidently urgent threats – like wars or economic collapse – are easy to put at the top of our list of priorities. But climate change is a very slow process (note the current sceptic line of decrying the lack of year-on-year warming as hoped-for proof that it’s all been a big mistake), and one where cause and effect (CO2=climate disasters) are not at all obvious at any intuitive level, hence the continuing predominance of wishful thinking, conspiracy-theorising and outright denial. Climate change clearly does not engage our natural psychological self-defence mechanisms.
This is the value of the 100 months campaign, which injects a sense of urgency into what is in reality a very slow process of cooking ourselves. We need to frame this issue as an urgent one to generate anything like an appropriate response, and indeed NEF explicitly uses the wartime analogy. But the drawback is also clear: in January 2017, after the deadline passes, people might either become fatalistic (“we’ve passed the tipping point, so let’s give up”) or might turn increasingly sceptical (“things don’t look any different – I thought you said the world was going to end?”). In reality, this is a matter of risk analysis: how much risk of destroying our planetary habitat are we prepared to bear in order to keep on burning fossil fuels? Quite a lot, it would seem.
This article was first published in the Guardian on 1 August 2008
Comments
2muchgovt
August 1st, 2008 at 01:57 PM
It is pathetic to see the volume of fear-mongering advance as the case for global warming wanes in the public eye, as the lie of consensus is exposed and as the evidence mounts against the case for AGW. I can think of no aspect of the theory of AGW which has not now been falsified by the evidence: The ability of GCMs to forecast, tropospheric warming (not there), net feedbacks (not positive), climate sensitivity to 2xC02 , unprecedented (non-geologic) warming, ocean heat content. The list goes on an on. Give it up and find some other way to fulfill you Bolshevic – greenie dreams.
Douglas Coker
August 1st, 2008 at 02:40 PM
2muchgovt Ehhh!
Another ranty denialist nut-job trolls by.
Douglas Coker Enfield Green Party
2muchgovt
August 1st, 2008 at 06:51 PM
Before you wet your pants about the next hundred months, you might want to look at the data on the last 100: http://www.junkscience.com/MSU_Temps/MSUvsRSS-m.html
Douglas Coker
August 1st, 2008 at 09:05 PM
2muchgovt
You display a serious lack of experience in this debate. Attempting to get us to engage with tired old denialist debates which are history won’t work.
My last on this. I’ve got better things to do with my time.
Douglas Coker Enfield Green Party
Horizon
August 1st, 2008 at 09:40 PM
James Lovelock was right. “Enjoy life while you can. Because if you’re lucky it’s going to be 20 years before it hits the fan.”
Vinny Burgoo
August 1st, 2008 at 10:23 PM
There’s something very weird about that onehundredmonths.org website, and I don’t mean the weirdness of picking a number at random and claiming, entirely sans evidence, that we’re all doomed. No, the REALLY weird thing about that website is that if you leave it to sit for a minute or so it suddenly starts eating processing power. Apart from this being a real nuisance (everything else slows to a crawl), it’s a big eco-naughty. I reckon it wastes about 75 Watts at my end. Quelle wanqueurs! (By the way, the link to the technical note PDF doesn’t work.)
Tony
August 2nd, 2008 at 12:03 AM
As Madonna said at liveearth “Clap your hands if you want to save the planet” or somesuch nonsense. Go Mark go save us all Christ on a bike I’m gonna throw up my breakfast.
mark lynas
August 2nd, 2008 at 09:21 AM
@ Vinny Burgo I noticed that about the onehundredmonths site too – my computer slowed right down, but I couldn’t figure out why. I’ll email the NEF people and get them to check it out. I’ve fixed the PDF link too – someone moved it. Sorry about that.
@ 2muchgovt None of us have time to deal with your inverse reality world. Please go elsewhere.
Green
August 6th, 2008 at 04:21 AM
After you’re done clapping, you can actually do something by going to this website: http://www.greengroove.org
Conduct a phased withdrawal on catastrophic climate change.
Read more by going to http://www.greengroove.org/idea.html
We’re in this thing together ; )
anon
August 6th, 2008 at 05:58 PM
anon August 6th, 2008 at 04:40 PM
Six Degrees put to paper what I have been researching the past two years. I came to the same depressing conclusions intuitively. There is one variable out there that is a solution, albeit a hard one. It would cause almost the instantaneous reduction of fossil fuel consumption across the globe. It would allow peak co2 loads to fall and the warming of climate be less than 3c. In addition to my research on climate change, I follow the CIDRAP website for statistics on communicable, tropical and mesquito born diseases. The medias attention about Avian Flu has died down but scientists are still diligently tracking the outbreaks and ferociously working toward a vaccine to prevent a pandemic that would leave approximately 1/3 of the world’s population alive, and the infrastucture of all nations in such desertion, that commerce by means of fossil fuels will quickly abate. It would force the remaining society to return to local farming practices, but as humans, we are very adaptable. It would prevent billions of people from starving to death, stop the destruction of ecosystems and give most species a chance to survive. Disease is a natural component of the checks and balances set to kept any population of species from overgrowth. It is a much gentler way of dying than starvation, thirst, homelessness and anarchy. Such a simple solution, yet we are horrified at the idea of a pandemic that could save the world for future generations. Haven’t we been selfish enough? When will we love the earth and its inhabitants enough to save it for future generations? And what are we saving these billions of people for? To die agonizing deaths by starvation, thirst, and war? I pray every night for a gentle, peaceful death, and that the world be saved. I doubt it will be if left up to us, but sometimes God can do for us that we can’t do for ourselves. By the way, they are doing clinical trials on the attenuated virus vaccine now, and it is showing promise. Humans are so smart now we will condemn ourselves and the earth to a horrible annihilation. Leave
Pauline van der Hoff
August 7th, 2008 at 02:47 PM
That’s a new one – allowing vast numbers of human beings to die in a flu pandemic by deliberately not developing a vaccine to mitigate it? What a sad individual “Anon” must be – no wonder they are “Anon”! I would like to know why Mark Lynas has failed to mention anywhere in his chapter on the mass extinction in the Permian, the high probability that an asteroid or comet strike was the cause. Just as it was at the end of the Cretaceous, (Alvarez et al). Balanced reporting? Of course not.
Lynn Vincentnathan
August 7th, 2008 at 10:05 PM
2muchgovt, seems you’re worried about too much government if we address AGW. Problem is the world might devolve into both chaotic anarchy AND extreme totalitarian regimes IF AGW is not mitigated (just think how ready Americans were willing and eager to give up their freedoms after 9/11, and only from fear of threats). When the real AGW effects start overwhelming societies, that’s when we’ll see Much2muchgovt Much2late.
So think of a bit of govt regs and policies to mitigate AGW as a sort of innoculation against AGW effects, including 2muchgovt.
Or, conversely we could just get rid of all tax-breaks and subsidies to the fossil fuel industries and at least partly internalize some of their externalities (includ some costs of their harms), so as to give alt energy a level playing field. When petrol goes up to $10+ a gallon as a result, and coal likewise goes up, then solar and wind will begin to look darned good.
Then we’ll be able to have LessGovt AND solve AGW.
Gaya
August 17th, 2008 at 09:36 PM
Dear Mark Just want to say that I love your books. Like mentioned earlier – finally a reality check on global warming (does AGW mean that? -I’m Swedish) as opposed to Lovelocks almost religious delirious ravings about Gaya( – the name I took as mine many, many years ago). What I can’t figure out, is exactly what scenario that will unfold first. There are so many threats these days – new bacteria, new viruses, exposure to contaminated air, water and soil. Food grown in soil fertilized by sludge (?) from purification plants with heavy metals. And then the storms, the floods and the temp. extremes both up and down. Here, rocks are being covered in moss and lichen because of the heavy and frequent rains. Etc etc. Unfortunately I don’t see reason and logic stepping up to the challenge of undoing our mistakes. Of course – the isolated cases of laudable solutions, but generally we are just dabbling at ecothinking by returning cans and plastic and paper and metals to the recycling plant thinking that that will certainly fix everything. Sorry to be so pessimistic, but You! have done a great job of trying to influence the powers into changing their ways!! Thanks! Gaya
Wayne McKenzie
August 25th, 2008 at 04:45 AM
I have to agree with ‘anon’, there are too many people on this planet. When other species have a population explosion (like mice in Australia relatively recently) nature deals with them within a generation and things are back to normal. Humans are too clever by half and it will take only something that we can create to knock us into line. That something is human induced global warming. So sad we have to take so many species with us.