Here’s a great example of why not to wade into long-running scientific arguments without the faintest idea what you’re talking about. David Whitehouse recently wrote an article for the New Statesman, “Has global warming stopped?”, which put forward the case 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.” According to his blurb, Whitehouse “was BBC Science Correspondent 1988–1998, Science Editor BBC News Online 1998–2006 and the 2004 European Internet Journalist of the Year” and “has a doctorate in astrophysics” – so he ought to have some inkling not only of reasonable scientific method, but also of responsible journalism. In his article, he casts himself as an heroic loner standing up to an oppressive orthodoxy – writing about the “apocalyptic” predictions of climate change, and twice making ironic reference to the “heresy” of rejecting the notion of anthropogenic climate change. We’re in the realm of domineering religious zealots, then, cowing dissenters into line, whom Whitehouse, like a kind of latter-day Galileo, is brave enough to stand up and challenge.
Unfortunately, Whitehouse’s position is not only wrong, it seems to be the sort of mistake impossible to make without either a fundamental ignorance of, or a willful blindness towards, the science involved. Given that the climate is a complex and chaotic system, the increasing levels of CO2 do not lead in a direct way to year-on-year increases in temperature, as you can see from the graph above (courtesy of the realclimate blog) – what they do lead to, as is unavoidably clear from even a brief look at overall pattern, is a general upward trend. The blue lines in the graph represent different trends across eight-year periods. As Mark Lynas points out, Whitehouse could have made such a cherry-picked assertion during a period at which any of these blue lines was pointing downwards – including “between 1983 and 1985, between 1990 and 1995, and, if you take the anomalously warm 1998 as the base year, between 1998 and 2004” and he would have been equally wrong to do so. The data on year-on-year temperature variation since 2001, then, don’t tell us anything like what Whitehouse claims. As pointed out by realclimate, his method “makes as much sense as analysing the temperature observations from 10-17 April to check whether it really gets warmer during spring”.
The denial of anthropogenic climate change has become a flourishing little industry of fashionable contrarians, all claiming to have been silenced, marginalized or censored by the big, bad climate change religion. Yet paradoxically these same folks get to make prime-time Channel 4 documentaries; their arguments are trotted out in the pages of the Daily Mail, the Telegraph, and now the New Statesman; they continue to pop up on the BBC; and high-profile presenters echo their spurious arguments. Have a look at this disgraceful performance from Kirsty Wark on Newsnight – in her words:
“We know the terror threat is a real and present danger – very recently of course, the burning car was driven into Glasgow airport. But according to NASA now, 1998 is no longer the hottest year, 1934 was – so surely there are still arguments to be had over climate change …?”
Could this be the logical non sequitur of the decade? You can find out what this difference actually meant from Gavin Schmidt of the NASA Goddard Institute for Space Studies:
“The net effect of the change was to reduce mean US anomalies by about 0.15 ºC for the years 2000-2006. … In the global or hemispheric mean, the differences were imperceptible (since the US is only a small fraction of the global area). …
“Sum total of this change? A couple of hundredths of degrees in the US rankings and no change in anything that could be considered climatically important (specifically long term trends).”
As Schmidt notes further:
“However, there is clearly a latent and deeply felt wish in some sectors for the whole problem of global warming to be reduced to a statistical quirk or a mistake.”
In this instance, that desire apparently extends to the presenter of the BBC’s flagship news and analysis programme. And, as it now turns out, to BBC News Online’s former Science Editor.
To repeat what should now be a familiar argument, these people don’t even have to win the debate to be effective: they simply need to feed the public perception that the issues are not yet settled, and the more doubt they succeed in generating, the greater will be the subsequent delay. Meanwhile on planet earth, the indications are that the predictions of climate scientists have hitherto been far too conservative – climate change is proceeding further and faster than previously imagined. We are running out of time. And we are still being misled.