I AGREE with R Quirk that the world population explosion is a problem but it is not as simple as that (Letters, March 12, 'What Greta doesn't realise').

People in the developing countries see the lifestyle we enjoy, and understandably, they want the same. Thus, although Britain's contribution to carbon dioxide emissions appears small, the potential impact is much bigger. We must, therefore, be seen to be taking action.

Also, it is not only the young who to blame. We are all guilty with our passion for cars, foreign holidays, nice semi-detached houses built on greenfield sites miles from our places of work, etc.

In respect of carbon dioxide emissions, when I started studying chemistry in the late 1950's the concentration of CO2 in the atmosphere was approximately 300 parts per million (ppm). The latest recorded figures indicate a concentration of slightly over 400ppm.

Prior to the Industrial Revolution, although most of the CO2 emissions were from natural sources, nature had ways of removing them: photosynthesis, rainwater scrubbing, etc. The concentration thus followed a natural pattern. Human activity has overloaded this process, hence the continuing rise.

Technology will, undoubtedly, develop ways to combat this but this takes time. If we do nothing, it may come too late.

Brian Moore