How to save us from climate-change doomsayers

"We're doomed; we're all doomed," as Private Fraser of "Dad's Army" fame would have it.

Another report on climate change this week suggests the Arctic permafrost is melting more quickly and will release much more carbon into the atmosphere than previously thought as the plant material held stably below freezing turns to decomposing mush.

It will cause a vicious cycle of more warming therefore more melting and therefore even more warming, the report from the UN Environment Program suggests.

It is a bit like the vicious cycle of the melting icecaps and glaciers. As the ice melts there is less reflective white stuff to send heat back into space and more dark sea to absorb it. So the earth heats faster than would be the case with just the extra carbon from industrialisation going into the atmosphere.

Well, we have heard all these doomsayers before haven't we? And we are still here. Surely, the earth is robust enough not to worry too much about some human-made gas. And the UN and climate scientists are in a green-communist conspiracy to destroy capitalism, freedom and liberty.

Well, that is what self-interested industries would have you think. And so would some self-interested politicians. A few maverick scientists and commentators have seen their chance to be noted as brave and healthily sceptical people willing to buck the conventional view. They say that there is not enough evidence of warming, or enough evidence that humans have caused it. Or that the earth has natural warming and cooling cycles and this is nothing to worry about.

Unfortunately, the theory of human-made climate change is fast becoming a minority opinion among the general population. And how nice it would be to not worry about the potential for catastrophic change or the possibility that our generation will leave the world a much worse place for our grandchildren than we inherited.

The change in public opinion is evidence that the world's scientists are failing us – badly. They are being far too cautious in their evidentiary requirements. They are being negligent in their duty to explain things to the public. They are being too inactive in advocating suggestions about what should be done about their scientific findings.

Yes, of course people should be sceptical, but not sceptical forever or sceptical in the face of ever-mounting convincing evidence – a bit like the tobacco-cancer link.

But one thing the climate-change sceptics are right about is that we have heard all this before – indeed several times.

Two occasions were especially instructive: the time in 1962 when the doomsayers, in particular Rachel Carson in "Silent Spring", said the insecticide DDT would destroy not only insects but the birds and the rest of the food chain, and the time in 1974 when University of California chemists Frank Rowland and Mario Molina said that chlorofluorocarbons (CFCs) would result in the destruction of the ozone layer which protects the earth from deadly ultra-violet radiation.

What happened with those pronouncements? Industry went on the attack. For example, biochemist and former chemical industry spokesman Robert White-Stevens stated, "If man were to follow the teachings of Miss Carson, we would return to the Dark Ages, and the insects and diseases and vermin would once again inherit the earth."