Has global warming really stopped?

Mark Lynas responds to a controversial article on newstatesman.com which argued global warming has s

On 19 December the New Statesman website published an article which, judging by the 633 comments (and counting) received so far, must go down in history as possibly the most controversial ever. Not surprising really – it covered one of the most talked-about issues of our time: climate change. Penned by science writer David Whitehouse, it was guaranteed to get a big response: the article claimed that global warming has ‘stopped’.

As the New Statesman’s environmental correspondent, I have since been deluged with queries asking if this represents a change of heart by the magazine, which has to date published many editorials steadfastly supporting urgent action to reduce carbon emissions. Why bother doing that if global warming has ‘stopped’, and therefore might have little or nothing to do with greenhouse gas emissions, which are clearly rising?

I’ll deal with this editorial question later. First let’s ask whether Whitehouse is wholly or partially correct in his analysis. To quote:

"The fact is that the global temperature of 2007 is statistically the same as 2006 as well as every year since 2001. Global warming has, temporarily or permanently, ceased. Temperatures across the world are not increasing as they should according to the fundamental theory behind global warming – the greenhouse effect. Something else is happening and it is vital that we find out what or else we may spend hundreds of billions of pounds needlessly."

I’ll be blunt. Whitehouse got it wrong – completely wrong. The article is based on a very elementary error: a confusion between year-on-year variability and the long-term average. Although CO2 levels in the atmosphere are increasing each year, no-one ever argued that temperatures would do likewise. Why? Because the planet’s atmosphere is a chaotic system, which expresses a great deal of interannual variability due to the interplay of many complex and interconnected variables. Some years are warmer and cooler than others. 1998, for example, was a very warm year because an El Nino event in the Pacific released a lot of heat from the ocean. 2001, by contrast, was somewhat cooler, though still a long way above the long-term average. 1992 was particularly cool, because of the eruption of a large volcano in the Philippines called Mount Pinatubo.

‘Climate’ is defined by averaging out all this variability over a longer term period. So you won’t, by definition, see climate change from one year to the next - or even necessarily from one decade to the next. But look at the change in the average over the long term, and the trend is undeniable: the planet is getting hotter.

Look at the graph below, showing global temperatures over the last 25 years. These are NASA figures, using a global-mean temperature dataset known as GISSTEMP. (Other datasets are available, for example from the UK Met Office. These fluctuate slightly due to varying assumptions and methodology, but show nearly identical trends.) Now imagine you were setting out to write Whitehouse’s article at some point in the past. You could plausibly have written that global warming had ‘stopped’ between 1983 and 1985, between 1990 and 1995, and, if you take the anomalously warm 1998 as the base year, between 1998 and 2004. Note, however, the general direction of the red line over this quarter-century period. Average it out and the trend is clear: up.

Note also the blue lines, scattered like matchsticks across the graph. These, helpfully added by the scientists at RealClimate.org (from where this graph is copied), partly in response to the Whitehouse article, show 8-year trend lines – what the temperature trend is for every 8-year period covered in the graph.

You’ll notice that some of the lines, particularly in the earlier part of the period, point downwards. These are the periods when global warming ‘stopped’ for a whole 8 years (on average), in the flawed Whitehouse definition – although, as astute readers will have quickly spotted, the crucial thing is what year you start with. Start with a relatively warm year, and the average of the succeeding eight might trend downwards. In scientific parlance, this is called ‘cherry picking’, and explains how Whitehouse can assert that "since [1998] the global temperature has been flat" – although he is even wrong on this point of fact, because as the graph above shows, 2005 was warmer.

Note also how none of the 8-year trend lines point downwards in the last decade or so. This illustrates clearly how, far from having ‘stopped’, global warming has actually accelerated in more recent times. Hence the announcement by the World Meteorological Organisation on 13 December, as the Bali climate change meeting was underway, that the decade of 1998-2007 was the “warmest on record”. Whitehouse, and his fellow contrarians, are going to have to do a lot better than this if they want to disprove (or even dispute) the accepted theory of greenhouse warming.

The New Statesman’s position on climate change

Every qualified scientific body in the world, from the American Association for the Advancement of Science to the Royal Society, agrees unequivocally that global warming is both a reality, and caused by man-made greenhouse gas emissions. But this doesn’t make them right, of course. Science, in the best Popperian definition, is only tentatively correct, until someone comes along who can disprove the prevailing theory. This leads to a frequent source of confusion, one which is repeated in the Whitehouse article – that because we don’t know everything, therefore we know nothing, and therefore we should do nothing. Using that logic we would close down every hospital in the land. Yes, every scientific fact is falsifiable – but that doesn’t make it wrong. On the contrary, the fact that it can be challenged (and hasn’t been successfully) is what makes it right.

Bearing all this in mind, what should a magazine like the New Statesman do in its coverage of the climate change issue? Newspapers and magazines have a difficult job of trying, often with limited time and information, to sort out truth from fiction on a daily basis, and communicating this to the public – quite an awesome responsibility when you think about it. Sometimes even a viewpoint which is highly likely to be wrong gets published anyway, because it sparks a lively debate and is therefore interesting. A publication that kept to a monotonous party line on all of the day’s most controversial issues would be very boring indeed.

However, readers of my column will know that I give contrarians, or sceptics, or deniers (call them what you will) short shrift, and as a close follower of the scientific debate on this subject I can state without doubt that there is no dispute whatsoever within the expert community as to the reality or causes of manmade global warming. But even then, just because all the experts agree doesn’t make them right – it just makes them extremely unlikely to be wrong. That in turn means that if someone begs to disagree, they need to have some very strong grounds for doing so – not misreading a basic graph or advancing silly conspiracy theories about IPCC scientists receiving paycheques from the New World Order, as some of Whitehouse’s respondents do.

So, a mistaken article reached a flawed conclusion. Intentionally or not, readers were misled, and the good name of the New Statesman has been used all over the internet by climate contrarians seeking to support their entrenched positions. This is regrettable. Good journalism should never exclude legitimate voices from a debate of public interest, but it also needs to distinguish between carefully-checked fact and distorted misrepresentations in complex and divisive areas like this. The magazine’s editorial policy is unchanged: we want to see aggressive action to reduce carbon emissions, and support global calls for planetary temperatures to be stabilised at under two degrees above pre-industrial levels.

Yes, scientific uncertainties remain in every area of the debate. But consider how high the stakes are here. If the 99% of experts who support the mainstream position are right, then we have to take urgent action to reduce emissions or face some pretty catastrophic consequences. If the 99% are wrong, and the 1% right, we will be making some unnecessary efforts to shift away from fossil fuels, which in any case have lots of other drawbacks and will soon run out. I’d hate to offend anyone here, but that’s what I’d call a no-brainer.

Mark Lynas has is an environmental activist and a climate change specialist. His books on the subject include High Tide: News from a warming world and Six Degree: Our future on a hotter planet.
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British politics and the lost art of rhetoric

Hilary Benn and others were acclaimed for their speeches in the Syria debate in the Commons. But if this was the House at its best, its best is not good enough.

When, after almost 11 hours of debate on 2 December, the Foreign Secretary, Philip Hammond, stood up to say that Hilary Benn’s argument for intervention in Syria would “go down as one of the truly great speeches made in the House of Commons”, few inside or outside the chamber disagreed. Asa Bennett in the Telegraph wrote that Benn had shown “a tenacious grasp of detail in his forensic analysis”, while Martin Kettle in the Guardian called his speech “politically elevating”.

It was not the only acclaimed intervention. Lord Harries praised the “excellent debates”, which had been “at once deeply felt and serious and informed and rational”. Benn said, “We have heard a number of outstanding speeches”; Hammond, too, announced that they had “done justice to the gravity of the subject”. Then, using one of the oldest clichés in politics, the Foreign Secretary added: “Today we saw the House at its best.”

If that was the House at its best, then its best is not nearly good enough. There were a few good interventions but, on the whole, the standard of debate was low, with some of the highest praise reserved for the especially poor performances.

The word “forensic” was used a lot by commentators and MPs but if you take an intellectual scalpel to Benn’s speech, for instance – the supposed highlight of the day – little stands up to scrutiny. Its impact owed more to its bold and direct challenge to Benn’s party leader than to its intellectual content. It serves as a case study on how weak arguments and misleading rhetoric can move and persuade a rationally illiterate parliament and people.

To say that the arguments were poor is not just another way of saying that I did not buy their conclusions. A good argument presents a case that demands a careful response, whether you ultimately accept it or not. A bad one commits an error or deploys a fallacy so obvious that the only response it requires is to point out the fundamental flaw in the reasoning. Benn’s arguments were almost all of this latter kind.

One of the most common features of a poor argument is that it fails to address the core issue, either missing the point or attacking a straw man. Take Benn’s argument that the UN Security Council Resolution 2249 is “asking us to do something, it is asking us to do something now, it is asking us to act in Syria as well as in Iraq”. Given this, he asked, “Why would we not uphold the settled will of the United Nations, particularly when there is such support from within the region, including from Iraq?” Even setting aside the significant but generally unnoticed slide from the recent view of the 15 members of the UN Security Council to the “settled will of the United Nations”, this argument misses the point. The main question for all but a handful of pacifists is not whether it would be good to do something but whether something good can actually be done.

The UN Security Council called for nations “to take all necessary measures” but a measure can only be necessary if it is effective. That was what opponents of the motion doubted and nothing that Benn said about the UN addressed that. Too often, MPs spoke as if the issue at stake were one of high principle, when for most the nub of the issue was the evidence for the efficacy of the proposed actions.

Benn repeatedly used the tactic of asking rhetorical questions along the lines of: “Can we really stand aside and refuse to act fully in self-defence against those who are planning these attacks?” That takes for granted both that acting would be effective self-defence and that the alternative to the proposed action was merely “stepping aside”. “Can we really leave to others the responsibility for defending our national security?” he asked, which presupposes that other western powers are indeed defending us by their actions, when many believe that they are doing no such thing. “Should we not play our full part?” he asked, assuming that extending our role is playing a “full part”, rather than simply playing a wrong part.

On top of all that, Benn resorted to the cheap claim that failing to act would send the wrong message to our friends and allies. That’s an argument used to decry sex education, for fear that it would send the message that children should be sexually active; or to deny people the right to choose the time and manner of their own deaths, for fear of sending the message that the weak and ill are of less value. Whenever such arguments are used, it is almost always the case that there is no necessary link between the proposed action and the dreaded message. What message is sent depends on how things are done, not just whether they are done. Britain could have refused to take part in air strikes in Syria, offering instead a metaphorical V-sign to its allies or trying as hard as it can to counter the threat of Isis in other ways.

My list of Benn’s fallacies is not yet exhausted but there is a more serious issue here than the failings of one politician who did better than most. Other widely praised speeches were much worse, most notably Margaret Beckett’s. Even a sixth-form student of critical thinking would spot the false choice that she offered opponents in her question, “Should we take no further action against Da’esh, who are themselves killing innocent people and striving to kill more every day of the week? Or should we simply leave it to others?” – as though air strikes were the only thing that western powers could do.

This use of false dichotomies was characteristic of the whole debate. It took Labour’s Chi Onwurah to point out, “The Prime Minister spoke often of the choice between action and inaction but those of us who will be voting against the air strikes also want to see action . . . cutting off the financial supplies to Da’esh that buy the bombs and help to radicalise recruits.”

Like Benn, Beckett also offered several false analogies, pointing to the efficacy of bombing in Kosovo, Kobane and Sierra Leone, when circumstances were very different in each case and are not comparable to the situation in Syria today.

Although I have focused on two pro-bombing speeches, what concerns me here is not which side was right but the quality of the debate. It is possible to have poor arguments for the right conclusion. That there were more bad speeches on the pro-intervention side merely reveals that the onus was on supporters of air strikes to come up with arguments that answered the concern that they would cause more harm than good.




The poor standard of debate in our nation’s most important political chamber reflects the broader parlous state of the art of rhetoric. Rhetoric has gained something of a bad name, being associated with the use of words to persuade, irrespective of the rights and wrongs of the conclusion that this persuasion aims at. It doesn’t help that the word “persuasion” is now associated primarily with advertising, marketing and spin, the modern dark arts that seek to bend us to others’ will.

In its original sense, however, rhetoric, properly used, was a respectable skill. Aristotle wrote the first major treatise on the subject, in which he distinguished between three kinds of persuasion. The first was rooted in ethos (character). “Persuasion is achieved by the speaker’s personal character when the speech is so spoken as to make us think him credible,” he wrote. “We believe good men more fully and more readily than others.” Benn exudes ethos – he is admired by all parties as a man of integrity and principle. It is notable that several of the other most rated speakers were elder statesmen and stateswomen respected for long service: Gerald Kaufman, Alex Salmond, Margaret Beckett, Alan Johnson. Aristotle would not have been surprised that these were among the most convincing in the debate.

The second form of persuasion uses pathos (emotion). This we saw in spades, with many referring to the “impassioned” nature of the debate, as though that were clearly a good thing. The widespread use of “Da’esh” was emotive – those speaking used the term, which Isis is known to dislike, in order to belittle it. Benn pulled many emotional strings, most obviously when he listed the various atrocities committed by Isis and concluded, “If it had happened here, they could have been our children.”

This is very effective but it does not address the central issue, which is what we can effectively do about it. There was also a dash of pathos in his concluding appeal to Labour’s historical internationalism, an attempt to stir an elevated feeling of universal benevolence. But this, too, lacked substance, since being in favour of internationalism does not entail supporting all international interventions.

The final element of the rhetorical triad is logos (reason). Contemporary rhetoric is good at harnessing the power of personality and emotion but has very little skill in reasoning. For Aristotle, however, this was a crucial part of the mix. A person in command of the means of persuasion “must, it is clear, be able to reason logically, to understand human character and goodness in their various forms, and to understand the emotions”. Without logos, rhetoric becomes mere oratory, which is precisely what Benn’s speech was: an impressive oral performance but not one that displayed the virtues of good reasoning.

Today, logos is very much the junior member of the rhetorical club. The poverty of logos in parliament reflects the poverty of logos in society. Our culture values emotion and authenticity above logic and rationality. It is perhaps telling that there is a thriving all-party parliamentary group for mindfulness but not one for philosophy.

Champions of logos have been lamenting for decades that we don’t spend enough time teaching children to think. Instead, we coach them to pass examinations. Universities, independent schools and some aspiring state ones maintain the tradition of debating societies but I have never been convinced that these nurture good thinking skills. Debating rewards the clever, the quick-witted, the charismatic. Success is measured by the number of ayes you receive at the end, not on the quality of your arguments. Parliament, especially during Prime Minister’s Questions, often resembles one of these undergraduate debates, in which discussion is a kind of competitive sport rather than a serious attempt to arrive at the truth.

Not only do we not teach people to think, we also seem to have lost faith in the power and value of reason. The cognoscenti know that we are ruled by our hearts, not our brains, or rather that our brains are emotional machines, not logical engines. These cynics point to work by the psychologist Daniel Kahneman, who has argued persuasively that the brain uses two different systems. System one is fast, automatic, emotional, subconscious and “hot”. System two is the slow, painstaking, calculating, conscious, “cold” mind praised by philosophers. The problem is that system one does most of the work and much of what system two does is simply to provide rationalisations for what system one has already decided. On this view, Aristotle only gave ethos, pathos and logos equal esteem because he suffered from the typical philosopher’s bias of overestimating our rational capacities.

This is, however, a terrible misunderstanding of the truth that Kahneman has revealed. Proof of the error is that he has not persuaded anyone of the truth of his theories merely through his reputation and the use of emotional manipulation. He has shown it by evidence and argument, by careful steps of reasoning that lead you back to observations that are demonstrably true. Kahneman’s account of the power of pathos is, in reality, the perfect example of Aristotle’s logos. His theory “is persuasive and credible either because it is directly self-evident or because it appears to be proved from other statements that are so”.




It is true that we now know that, in practice, ethos and pathos are the automatic prime movers of persuasion. But we are not obliged always to follow our most immediate inclinations. Logos allows us to pause and examine arguments and to see if they stand up. If they don’t, we can reject them, no matter how much we may side with their proponents or want to agree with them.

It would be absurd to claim that the Syria debate was devoid of any rational argument. Benn offered two that require an answer and are not just fallacious. Against those who said that air strikes alone would not defeat Isis, he argued: “They make a difference, because they give it a hard time, making it more difficult for it to expand its territory.” You may or may not agree with this but it is correct that the statement “Air strikes cannot wipe out Isis” is not a sufficient argument against them, because to degrade the group’s capacity to launch attacks and train terrorists would be a clear benefit. This point requires a response.

Similarly, Benn argued that even if the number of ground troops capable of being supported by air strikes was low, “The longer we leave taking action, the longer Da’esh will have to decrease that number.” This, again, is a challenge that opponents of air strikes need to meet. If – and it is a big if – the alternative to air strikes is the gradual elimination of all moderate opposition forces in Syria, is it better to let that happen or take a last, perhaps desperate, chance to support them?

Every other point that Benn made, however, somehow missed the point or distorted it. Others made an even bigger mess of it. David Cameron’s low point came when he ruled out the use of ground troops because their presence “can be a radicalising force and can be counterproductive”. If this is true of ground troops, it is simply implausible that it is not also true of air strikes. In both cases, people know exactly who is firing the weapons. By what strange principle does he think that they bear grudges against infantry but not pilots? Cameron’s logic could so obviously and easily have been turned against him and yet no one in the chamber picked him up on this.

Aristotle argued that however an argument is constructed, it is “persuasive because there is somebody whom it persuades”. Our problem today is that too many arguments that ought not to be persuasive nonetheless are. The only antidote to this is to strengthen our powers of reasoning, and rhetoric should be put back on the curriculum.

Julian Baggini’s most recent book is Freedom Regained (Granta)

This article first appeared in the 10 December 2015 issue of the New Statesman, The clash of empires