marklynas.orgHow climate change is blowing hot and cold 05 October 09
A rainy day in July does not falsify climate change. But understanding why not requires some scientific knowledge. (First published in the New Statesman.)
In dark moments, I sometimes catch myself listing reasons why the chance of humanity successfully tackling climate change is not very great. There’s the time lag (act now to stop disaster in 50 years), the diffusion of responsibility (what about all the Chinese?) and the expense – not to mention the entrenched interests of the fossil-fuel merchants.
What’s more, we can’t easily sense climate change. Planetary warming may seem real during a heatwave or a snowless winter, but what about a rainy day in July or a January freeze? Where’s your global warming then? Understanding why short-term fluctuations don’t tell us much about long-term trends requires a bit of scientific knowledge. Take the “global cooling” saga: great story, but very little basis in science, and what basis there is has been widely misunderstood.
The suggestion that global warming might stop for a few years gained much prominence after a paper (innocently entitled “Advancing Decadal-Scale Climate Prediction in the North Atlantic Sector”) was published in the journal Nature last year. The last line of the abstract set the shadowy corners of the blogosphere haunted by climate-change deniers (we call it the “denialosphere” for short) buzzing. “Our results suggest that global surface temperature may not increase over the next decade,” the scientists wrote, “as natural climate variations in the North Atlantic and tropical Pacific temporarily offset the projected anthropogenic warming” – though somehow the first part of the sentence generated more interest than the second.
No one who knows their climate onions ever expected global warming to be a linear trend of year-on-year temperature rises, and the continuing role of natural variability – in particular cycles in the world’s oceans, which store vastly more heat than the atmosphere – is a perfectly legitimate area of research. This is actually all rather technical and arcane: it’s about how best to tune the models that give us an insight into the globe’s likely climate future. But that’s fine – and it doesn’t falsify global warming: unless, that is, you’re a “climate sceptic”, desperate to add a tiny scrap of false scientific credibility to your ideological position.
Here is the shocking truth: global warming has “stopped” many times already – but it is still getting warmer. Two US-based climatologists recently published a fascinating paper in the journal Geophysical Research Letters simply entitled: “Is the climate warming or cooling?” They concluded that although it is true that if you draw a straight line from 1998 to 2008 “there is no real trend”, the same would go for the periods 1977-85 and 1981-89; even though, overall (between 1975 and 2008), there was “substantial warming”. How confusing.
And expect this confounding real-world complexity to keep on happening. Scientists at the Met Office’s Hadley Centre recently ran their model forward until the end of the century (ten times in total) and counted plenty of short periods (of a decade or less) when global temperatures fell or held steady. But overall, the model warmed by a couple of degrees by 2100 – and that’s what counts.
So no, a rainy day in July – or even a decade of little or no observed warming – does not falsify climate change. To understand why not, however, you need to comprehend basic-level statistics rather than rely on common sense. And that, I suppose sadly, is another one to add to my list.
Comments
Tom Allen
October 6th, 2009 at 06:36 AM
I think you’ve nailed it. Cherry-picking narrow statistical ranges is a favourite tactic of global-warming denialists, because – unfortunately – it’s so superficially convincing.
egipt al-mousa
October 6th, 2009 at 10:07 AM
The arithmetic of climate change mitigation centers on three main questions: How much greenhouse gas can we emit each year and still avoid dangerous climate change (the annual global carbon budget)?
Who gets to emit what portion of that annual global carbon budget? And who pays the financial and behavioral costs of changing from our current high-carbon global economy to the necessary low- or no-carbon economy? (Climate change adaptation is another important issue.)
pete best
October 6th, 2009 at 08:03 PM
the Hadley center are missing some data from the Arctic but GISS are not and hence no such anomaly exists for them.
Its the latest article over at realclimate.
Tony
October 7th, 2009 at 06:00 PM
Well I don’t know why exactly my postings have been deleted from this blog. Someone calling themselves Tony posted a comment some weeks ago which was a bit near the mark and that comment was deleted. I did post a comment straight after that calling myself Tony the original and best in a vain attempt to show that that previous posting had nothing to to with me.
Hey ho! Still back to the debate.
Reading Marks latest piece I have to bring up the point of the latest unveiling of the Emperors new clothes, namely the latest discrediting of the hockey stick graph which represents the cornerstone of climate change theory to this present day. Unless you live on Mars or read your news via the mainstream media outlets you cannot fail to have seen the scandal of the falsified tree ring data from Yamal. For the likes of Pete Best I’ve posted up a link which puts the story in simple terms.
http://wattsupwiththat.com/2009/09/30/a-must-read-the-yamal-hockey-stick-implosion-in-laymans-terms/
I’m off to the bookies now to place a bet on the most obvious rebuttal to this piece. I’ll let you know if I have won anything by reading the replies over the next few days (hopefully unless this is deleted).
G.R.L. Cowan
October 7th, 2009 at 10:27 PM
Actually I think it is common sense that random variations superimposed on a long-term trend will look like two steps forward, one step back, or two big steps forward and then a small one.
No-one would find this baffling if it referred to weekly business volumes in a downtown retail outlet as big-box outlets spring up on the outskirts of town. Well, no-one except an apologist for the big box chains.
(How fire can be domesticated)
Shane Hughes
October 9th, 2009 at 07:31 PM
why you’re still posting articles that attempt to prove the CC argument, i really don’t know. We’ve been arguing this for more than 30 years and it’s now time to focus on the solutions.
Pete Ridley
October 11th, 2009 at 08:11 PM
Shane (Hughes) the simple reason is that The (significant human-made global climate change) Hypothesis remains to be validated by scientists. In fact more and more scientists are acknowledging that there are too many uncertainties surrounding climate processes and drivers to be able to forecast what the future holds for us. As for solutions, humans have no means of changing climate change, only of adapting to live with whatever nature throws at us. That is what we should be concentrating on, not reducing our use of fossil fuels.
Best regards, Pete Ridley, human-made global climate change agnostic.
100fm6
October 12th, 2009 at 11:54 PM
“We’ve been arguing this for more than 30 years and it’s now time to focus on the solutions” yea, this summer I remember it as the hottest weather I ever lived in, now we are in Oct. however it is still warm in Egypt, It was never before !
Hans Verbeek
October 13th, 2009 at 06:58 AM
How about a pause of 2 decades (20 years) in Global Warming ? IPCC-member Mojib Latif is convinced that Global Warming will stop for 2 decades. In the meanwhile the economic recession will reduce our CO2-emission. This has already started. We have passed the peak of our industrial production (peakoil was in 2008). The IPCC-projections for CO2-emissions are far too high and totally wrong.
Rmoen
October 15th, 2009 at 02:41 AM
The wheels are coming of man-made global warming theory—as preached by the United Nations. There’s been no global warming for a decade, according to the BBC, New York Times and Christian Science Monitor (links follow). The UN’s climate scientists are back-pedaling like crazy. One of their own even says we are looking at another decade of cooling.
The simple truth is that America needs our own Climate Truth Commission. Outsourcing climate science to the UN makes no sense. The UN is more concerned about politics and funding than science. Plus, UN forecasts for the last 10 years do not fit what actually happened. The United States needs our own objective, transparent climate commission to think-through global warming.
—Robert Moen, www.energyplanUSA.com
http://news.bbc.co.uk/2/hi/science/nature/8299079.stm http://www.nytimes.com/2009/09/23/science/earth/23cool.html?_r=3&em http://features.csmonitor.com/discoveries/2009/10/10/biggest-news-youve-never-heard-earth-isnt-warming/
G.R.L. Cowan
October 18th, 2009 at 03:59 PM
It’s really hard to reduce CO2 emissions when so much of governments’ incomes are tied to them. Proposals for increased carbon taxation would aggravate this problem, except when they specify that the increased carbon loot be divided equally back out to the citizens.
But then the question should arise, why not start by doing this dividing-out with the existing daily gigabucks in carbon tax revenue.
Another option is to spend this enormous cash flow on atmospheric garbage collection, specifically, collection of the CO2 that is coproduced with the money. This turns out to be not as hard as it’s being made out to be.
(How fire can be domesticated)
Tony
October 18th, 2009 at 11:36 PM
Hi Pete. Good to see you’re still here. Well groundhog day on planet Earth. Usual suspects trying to break into a coal fired power plant in the English midlands. This time they are complaining about puppy dogs biting their arms as they attempt to scale the fence in order to cut off vital energy links to that area. So while saving the planet they tend to disregard the day to day lives of ordinary citizens, hospitals, the vunerable who have no clue as to why the lights might go out.
It occured to me that this highlights the ultimate stupidity of those who have fallen for the global warming/climate change hoax. The power of propaganda is frankly terrifying when the end result consists of the educated middle classes expending so much energy in order to “fight climate change”.
I know people can do stupid things but in this day and age the sight of intelligent people falling for the rubbish trickled down from the powers that be and putting their beliefs into subversive action takes ones breath away. I wouldn’t mind but most rebels without a cause at least do the movement some justice by taking part in actions that spring from ideas found on the back of rock album covers and “subversive” underground left of centre publications. But to take ones radical and rebellious notions from none other than ones own Governments and official lobby groups and lesser political parties really turns the notion of youthful rebelliousness on its head.
Perhaps this phenonema can actually be blamed on the demise of the vinyl album. Whereas once we got stoned in our bedrooms reading the endless ramblings of equally muddled thinking from our guitar heroes now there is only the cd cover at best or worse still the download option which goes straight to ipod. So no deep far out talk about “what a great world it would be if only people from all over the world would get naked and form a group hug”. Instead its corporate rock and corporate thinking and corporate rebellion on their terms. Gore, Stern, Moonbat and that advisor to fraud Gore and many others in the green movements officially sanction invasion of power plants and other such acts.
God I’d hate to be growing up today it’s such a bore. Nothing to fight against now that the establishment has set the rules as to who and what you can see as the enemy.
Who knows? Tomorrow gravity will be seen as the mortal enemy of the planet and all magnets will be banned. Or requistioned? Hmmmmn, I’ve just had an idea…..................