SIR, — Your correspondent Mr D. Reynolds is a hard man to convince. Not for the first time he has aired in your pages his scepticism about climate chaos and the need to take action (Herts Advertiser, April 3). Not for the last time, I am sure, I would lik

SIR, - Your correspondent Mr D. Reynolds is a hard man to convince. Not for the first time he has aired in your pages his scepticism about climate chaos and the need to take action (Herts Advertiser, April 3).

Not for the last time, I am sure, I would like to try to persuade your readers that Mr Reynolds is wrong.

I use the term "climate chaos" as that is becoming a more useful way to describe what we are seeing happening around the world. It's not simply "change" or "warming", but a range of increasingly-severe, seemingly-random events and effects.

With a rather odd array of statistics, Mr Reynolds compares the effect of human activity on the climate to the cooling effect of dipping an ice lolly in the sea. If one thing has been made clear over the last few years, climate chaos is not a straightforward subject. It is not possible to statistically prove much about it in the length of a letter.

But there are plenty of places one can find summaries from people who have had the time and expertise to work it out for us.

The Intergovernmental Panel on Climate Change is a good place to start. Established by the UN, it based its assessments on peer-reviewed research and published scientific and technical literature. Its conclusions have been startling in their simplicity - that climate chaos is happening and that it is to a large extent caused by human activity, and that we can and must do something to mitigate it.

Some people might be surprised that there are those who still believe we need do nothing. Most groups and individuals are now more focussed on how much can be done, and how quickly, not whether anything should be done at all.

Of course, Mr Reynolds is entitled to his opinion, and few things are ever 100 per cent certain. But what if he is wrong? By the time we knew that for sure, it would be too late. On the other hand, if we act to combat climate chaos and it turns out not to be the threat we thought, we will have simply taken sensible steps to reduce energy consumption and the depletion of the world's resources.

On car use in particular, and hence fossil fuel use, it is incontrovertible that the planet's supply of oil will not last forever. In fact there is overwhelming evidence that we have already reached "peak oil", and that supplies are now diminishing. If only to address this problem, we must shift away from our current pattern of ever-increasing use of fossil fuel before even more wars are fought over it.

SIMON GROVER,

St Albans District Green Party.