These are difficult times for climate scientists. The authors of the latest report by the Intergovernmental Panel on Climate Change (IPCC) concluded that the Earth was heating up and they were 95 per cent certain that human activity was the main cause of global warming.
This was strong stuff, as it came from an organisation that did not accept that climate change was mainly human-induced until 2007, a couple of decades behind some leading scientists in the field.
Yet the more certain the climate scientists become, and the more data they collect, the less ability they have to convince people to take action to address a threat which they believe could make large parts of the globe uninhabitable.
Opinion polls show that climate scientists face a strong headwind in developed countries. The number of people in Britain who do not believe in global warming has risen more than four-fold to 19 per cent since 2005, according to a survey published in The Times. A separate poll of 13 countries showed that the US, Britain and Japan were the most sceptical about human activity being responsible for climate change, a proposition that 58 per cent of Americans accept. In Australia, 45 per cent of people think environmental dangers are exaggerated.
Exasperated scientists have been asking how the climate sceptics have come to exert such influence on the debate. Part of the answer is that scientists work in a world of uncertainty. The conclusions of research are subject to endless refinement. The general public finds the concept of uncertainty unsettling and confuse it with ignorance.
By contrast, the sceptics have no such restraints. In Britain, the former Chancellor, Lord Lawson, now an outspoken climate change sceptic, dismissed the IPCC’s findings as “mumbo-jumbo” aimed at “credulous politicians and journalists”.
Scientific caution has increased as a result of some notable mistakes. The 2007 IPCC report predicted that the Himalayan glaciers could disappear by 2035, a claim now recognised to be wildly exaggerated. So the climate scientists find themselves failing on two fronts – their academic caution gives them no traction with the non-specialist and their mistakes are held to vitiate the whole theory.
Ultimately the scientific fraternity is facing a tougher task than defending a theory. For people to believe in a threat, it is helpful if they can put a face to it. With the right poster boy, people will believe almost anything: many believed the ludicrous fiction that Saddam Hussein could launch a chemical attack on British troops in Cyprus in 45 minutes.
Here there is no Doctor No against which the world can mobilise. Nor is there a mighty asteroid barrelling towards Earth, to hit us in 2035 and wipe out half of humanity. With no sign of human volition and no fixed appointment with catastrophe, climate change struggles to become more than a theory in the popular imagination.
It is not surprising then that the natural urge to discover a human face behind the threat has looked for conspiracy – and some people have found it in the scientists. The loudest voices in America see a conspiracy by a scientific-environmental lobby. The green movement are watermelons, according to this world view: green on the outside but communist red on the inside.
This conspiracy theory was given a boost in 2009 when hacked emails from the Climate Research Unit at the University of East Anglia were leaked. They appeared to show scientists manipulating the data to give clearer evidence of global warming, though the CRU said it was just robust academic debate taken out of context.
Scientists have to unravel the natural changes in climate – everyone knows that ice ages have come and gone – from the human-induced element. This is complicated, but the immediate problem for the IPCC is to explain why global warming has slowed since the 1980s, despite the growing amount of carbon dioxide and other greenhouse gases pumped into the atmosphere.
The IPCC offered journalists a lesson in the use of statistics, pointing out that 15 years is a blip in a climatologist’s timeline. “Due to natural variability, trends based on short-term records are very sensitive to the beginning and end dates and do not, in general, reflect long term trends”. True, but hardly a knockout blow. It does not alter the fact that for the lay person, what is before their eyes is more real than a 300-year temperature graph.
What we are seeing now is a divergence between the developed countries, or at least those in cooler climes, and those closer to the Equator. The opinion poll that showed the US, Britain and Japan as the most sceptical showed the reverse in Indonesia, Mexico and Hong Kong, where 87 to 93 per cent believed human activity was mainly responsible for climate change.
Clearly the risks of extreme weather events are more real in these countries, and the effect can be seen in politics. Mexico, for example, has passed its first climate change law and is tackling deforestation.
But science cannot be separated from politics and economics. In Japan, calls for the reduction in use of fossil fuels may be interpreted as propaganda for the nuclear industry, which is on the defensive after the Fukushima power plant disaster. In Britain, the environmental cause has been tainted by an angry debate over wind farms – the cost in higher energy bills to subsidise them, their unreliability as an energy source and general ugliness.
How will the Mexicans react when they face higher bills for green energy – particularly when the US to the north is, in the popular narrative, racing towards a bright economic future on the back of a boom in shale gas extraction?
In the end, people around the world want to protect their environment and they know the global population is going to rise from seven billion to 10-15 billion by the end of the century. How we get from that recognition to climate policies that people can agree on is a task that is barely begun.
On Twitter: @aphilps