I WAS recently told that carbon dioxide was irrelevant because there’s so little of it about – with nitrogen making up 78 per cent of our atmosphere, oxygen another 21 per cent and argon just below one, it meant that everything else, like nitrous oxide, methane and carbon dioxide is all crammed into less than one tenth of one per cent.

So, there’s not much CO2 but the nature of its chemical structure means that it has a controlling impact on our climate – the more of it the warmer it becomes as even this very small number of molecules prevents planetary heat loss.

Charles Keeling began measuring CO2 in 1958, two miles up in the sky on top of an Hawaiian mountain, and its been repeated every day since, most recently by his son. He was perplexed initially as the CO2 varied monthly but it soon became clear that it was seasonal and related to the growing season.

He also realised that overall it was steadily increasing, almost mirroring the growth in the world population. In 1960 there were only three billion folk, and in just forty years it doubled to over six billion by 2,000, and soon to be well over seven and a half billion by 2020.

Not only are there more of us to produce more CO2, and methane, from our car engines and cows, but we also now own much more as individuals than we did in the Fifties and Sixties.

Only 14 percent of households had a car in 1951 but by 2010 it had risen to 75 percent, with eight times more cars being sold in 2001 than in 1951. Flying, though, produces the most CO2 and the Heathrow passengers, some five million in 1960, are now 75 million, and increasing.

We really do need literally to keep our feet on the ground to avoid a soaking from the rising sea levels, with the inevitable warmer expanding water and melting ice that is only happening because we want to live for the minute and completely ignore our children’s future.