Professor Michael Kelly, pictured, was one of 43 Fellows of the Royal Society who wrote to the president to warn that it was in danger of violating its founding principle

Five years ago, I was one of 43 Fellows of the Royal Society – the first and arguably still the most prestigious scientific organisation in the world – who wrote to our then-president about its approach to climate change. We warned that the Society was in danger of violating its founding principle, summed up in its famous motto ‘Nullius in verba’ – or ‘Don’t take another’s word for it; check it out for yourself’.

The reason for our warning was a Society document which stated breezily: ‘If you don’t believe in climate change you are using one of the following [eight] misleading arguments.’

The implication was clear: the Society seemed to be saying there was no longer room for meaningful debate about the claim that the world is warming dangerously because of human activity, because the science behind this was ‘settled’.

We hoped we would persuade the Society to rethink this position. That document was revised so that the uncertainty involved in trying to model the climate was admitted. But since then the Society has become more, not less dogmatic – despite the fact that since we sent that letter, it has become evident that there is even more uncertainty than previously thought. Carbon dioxide levels in the atmosphere have continued to rise, but since 1998 there has been no statistically significant rise in global temperatures at all.

This flies in the face of the confident predictions made by nearly all the climate computer models that the temperature would continue to rise as it did from 1975 to 1998. More than 60 different explanations have been proposed to explain why this ‘pause’ or ‘hiatus’ has happened, and their sheer number is the clearest evidence that the system that climate scientists are seeking to model is irreducibly complex. Human-sourced carbon dioxide is at best one of many factors in causing climate change, and humility in front of this complexity is the appropriate stance.

Yet the Society continues to produce a stream of reports which reveal little sign of this. The latest example is the pre-Christmas booklet A Short Guide To Climate Science. Last year also saw the joint publication with the US National Academy of Sciences (NAS) of Climate Change: Evidence And Causes, and a report called Resilience. Through these documents, the Society has lent its name to claims – such as trends towards increasing extreme weather and climate casualties – that simply do not match real-world facts.

Both the joint report with the NAS and the Short Guide answer 20 questions on temperatures, sea-level rises and ocean acidification. But a report today by the academic council of the Global Warming Policy Foundation, which includes several Society Fellows and other eminent scientists, states the Society has ‘left out’ parts of the science, so the answers to many of the questions ought to be different.

I have personal experience of this selectivity. Last year, at the request of the president, I produced a paper that urged the Society’s council to distance itself from the levels of certainty being expressed about future warming.

I said it ought at least to have a ‘plan B’ if the pause should last much longer, so calling the models into still more serious question. I got a polite brush-off.

Prof Kelly said the Royal Society, pictured, was founded on the principle ‘Nullius in verba’ – or ‘Don’t take another’s word for it; check it out for yourself'

Professor Kelly fears the Royal Society has become more dogmatic when considering climate change

The great 20th Century physicist, Richard Feynman, wrote in his autobiography: ‘Details that could throw doubt on your interpretation must be given, if you know them. You must do the best you can – if you know anything at all wrong, or possibly wrong – to explain it. If you make a theory, for example, and advertise it, or put it out, then you must also put down all the facts that disagree with it, as well as those that agree with it.’ This the Royal Society has failed to do.

The reason for this lack of nuance seems to be that policymakers say they want ‘scientific certainty’. As an engineer, I find that amazing: we remain legally liable for what we say professionally, so will always qualify our statements. But the misleading lack of qualification in the statements made by the Royal Society and others is creating policy nonsense.

The Climate Change Act requires the UK to cut its CO2 emissions by 80 per cent from 1990 levels by 2050 – at mind-boggling cost. Generating electricity from windmills has contributed to electricity prices increasing by twice the level of inflation over the last decade, with further huge rises to fund renewable energy to come. Aluminium production is highly sensitive to energy prices, and most of the UK smelters have closed down – helping us reduce UK emissions, but also exporting jobs.

He claimed the commitment to slash CO2 levels by 80 percent from their 1990 levels by 2050 is mind-boggling

No one describes the consequence: we now import that aluminium from China, leading to CO2 emissions from shipping it here. Worse, most electricity in China is produced by coal, not gas, as in the UK. We are exacerbating the original global problem of global CO2 emissions, yet also pointing fingers at the Chinese. We really are leading the world in climate change hypocrisy.

The project to ‘solve the climate change problem’ is a modern version of the biblical Tower of Babel. We do not know how much the project will cost, when it will have been completed, nor what success will look like.

During my time as a government departmental Chief Scientific Adviser, I was always aware that politicians made the final decision on any issue on the balance of all the evidence. For this reason, civil servants are trained to draw their attention to all the upsides and downsides of taking a particular course of action.

Those who fail to provide balance are not giving advice, but lobbying. It is with the deepest regret that I must now state that this is the role which has been adopted by the Royal Society. And when scientists abandon neutral inquiry for lobbying, they jeopardise their purpose and integrity.

PROFESSOR MICHAEL KELLY IS THE PRINCE PHILIP PROFESSOR OF TECHNOLOGY AT CAMBRIDGE UNIVERSITY AND FELLOW OF THE ROYAL SOCIETY