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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Donald Trump’s hollow coronation

The presidential candidate was forced to wheel out family members at the Republican National Convention, as party grandees stayed away. 

For a member of what Donald Trump calls his silent majority, Jim Morrison, a haulier from California, talks a lot. “He is touching on things I feel – that millions of Americans feel – but I don’t have the microphone and can’t take on Washington,” Morrison said. The words tumbled from his mouth as he stood beside the blood-red cab of his lorry, which carried him from his home state to Cleveland, Ohio, on a seven-day journey in a “Truckers for Trump” convoy.

Trump had promised an unconventional Republican National Convention and Morrison was typical of the new breed of political activists attending their first Grand Old Party summer jamboree. The start of the four-day convention also offered both a taste of what a Trump administration might  look like and a summary of the factors that helped a bombastic billionaire and political novice secure the presidential nomination for the Republican Party.

The answers lay not just in the cavernous interior of the Quicken Loans Arena, where the delegates assembled, but also among the lawn-fringed public squares heaving with supporters and protesters vying to fly the most outrageous banners. Above all, they lay in the wide boulevards where heavy, concrete barricades had been laid to prevent terrorist attacks, and in the flags flying at half-mast overhead, marking America’s latest mass shooting.

The convention began just a day after three police officers were shot dead by a gunman in Baton Rouge, Louisiana. “It’s pathetic that our society has got to the point where they are doing this to our cops,” said Morrison, the trucker, firing gobbets of tobacco-coloured spit on to the pavement.

If one theme sums up the issues at stake in this election – from jobs to terrorism – it is insecurity. The terrorist attack in Nice merely stoked fears that had grown during the past year as Americans dealt with Islamic State-inspired attacks on home soil, the murder of police officers and a gaping racial divide.

In Cleveland, all this manifested in the city ordering an extra 10,000 sets of handcuffs, deploying 5,500 law enforcement officers and buying 300 bicycles for officers tasked with crowd control. Some of the measures were farcical – such as banning anyone carrying tennis balls from the convention environs – in a state where citizens are allowed to carry assault rifles openly.

This is the backdrop against which Trump delivers his hard-line message, warning that terrorists could arrive among Syrian refugees and that the country needs a wall on its southern border. Indeed, Monday’s theme was “make America safe again”, and outside the centre vendors hawked T-shirts portraying Trump as Captain America or Iron Man. “He’s a man to get things done, even if that might upset the PC crowd,” is how one delegate put it as she queued to get into the arena.

Political scientists have identified a trend in this election, suggesting that America’s two main political parties are shaking up not along the lines of left and right, but in terms of attitudes to authoritarianism. Many Republicans are looking for a strongman, according to research carried out by Matthew MacWilliams, founder of the political communications firm MacWilliams Sanders. In this context, Trump’s message – strong v weak, winners against losers, and a new nativism – is a guaranteed vote-winner.

For his opponents, it is not a new message. Edmund Berger, a writer and activist, said that Trump was just the latest “1 per center” to go after the working-class vote by ripping Band-Aids off society. “He’s stoking the fires of racial tension with his stuff on immigrants and hard-line foreign policy,” he said, sitting in Public Square, an open space that has been turned into a sort of Speakers’ Corner. “The hate can come out finally.”

The presumptive Democratic candidate Hillary Clinton was attacked relentlessly. “Trump v tramp”, read one banner, and the convention programme followed on from there. It included sessions on Bill Clinton’s sex life and scrutiny of her handling of the Benghazi attack, in which four Americans died in 2012.

Yet even the best-laid plans have a habit of coming unstuck around Trump’s idiosyncratic approach. During one of the most powerful sessions, as Patricia Smith, the mother of a state department officer killed in Benghazi, delivered a searing speech holding Clinton responsible for the death of her son, Trump phoned Fox News. Because of his live interview, the channel cut away from Smith’s speech, leading one of Fox’s analysts to call Trump’s timing “interesting”.

Nor did the programme live up to Trump’s frequent promises to add more showbiz to the convention. Republican royalty, such as the Bush family, stayed away, as did the party’s biggest celebrity supporters, including Clint Eastwood and Jon Voight.

Instead, the roster was padded by the sort of people known only to fans of daytime TV and wackier reality shows – and by Trump’s wife, Melania, and four of his children. The risks of that approach were evident on Monday night, after Melania’s speech bore more than a passing resemblance to a convention address by another prospective first lady, Michelle Obama, in 2008. The plagiarism controversy will reinforce existing concerns about the Trumps playing fast and loose with the rules.

Others in the audience saw another problem with relying on relatives rather than heavy-hitting conservatives. “I know he’s selected them to reflect the different facets of his personality,” said Theodore Golubrinski, a member of the Michigan delegation, “but this looks like a coronation.”

The suspicion is that Donald Trump’s Republican National Convention would also look like Donald Trump’s White House, with low-rent celebrities, fringe Republicans and naive family members making up the numbers.