SIR – Peter Rushforth seems to confuse weather with climate in his comments on CO2 (T&A, December 9). Climate is weather averaged over a 30-year period so a nippy night or two in December will have minimal effect on the trend of a warming planet.

I was surprised that he sees man as being separate from nature, when in fact we are the dominant species in the natural world with greedy habits that remove the trees, pollute rivers and oceans and change the climate.

Seven billion of us with human appetites for a century or more have a very significant influence on the planet.

Keith Thomson, Heights Lane, Bradford 9