YOUR correspondent R Quirk (Letters, February 20, ‘How can Greta be so precise?’) needs to get his head out of the sand.

Yes, the climate has varied over millennia in the past. But what is new is the unprecedented rapid increase in CO2 and other greenhouse gases in less than a couple of hundred years.

These increases have been documented in research on ice cores in Greenland and Antarctica. Bubbles in the ice preserve bits of the planet’s atmosphere. Analysis of ice laid down over many thousands of years shows an increase that correlates well with the Industrial Revolution and the ever-increasing use of fossil fuels since then.

So. please stop clinging to conspiracy theories, Mr Quirk, and listen to what the overwhelming majority of the world’s scientists are telling us.

Peter Freyhan