I am grateful to Dave Degen’s response to my People before Planet plea (Letters, June 28). He raises some important questions. Here is my response:

Computers can never accurately model reality. No matter how much data - from tree rings, ice-cores, satellite readings - you enter, you will never get a true picture of terrestrial weather because there are far more variables than are known and measured - and they balance each other. It is interesting that solar cycles more accurately match terrestrial weather fluctuations than anything humans are doing in terms of CO2 emissions. Plants take up CO2. Horticulturalists pump it into their green houses to boost crop growth; the planet is gently ‘greening’, as it has done many times in the geological past when CO2 levels were much higher than they are today. Greenland was once green; trees once grew in the Arctic; polar bears were once brown.

When rulers wish to expand their authority, they always invent a ‘doom scenario’. It’s an old trope. In medieval times, the church held out the threat of hell-fire - and accusations of ‘blasphemy’ always silenced debate. (Our geniuses in Whitehall have just reintroduced blasphemy laws!) Going back even further, the witch-doctor or shaman would invent a ‘doom scenario’ to induce fear and compliance. So called ‘climate science’ has been seriously politicised. Those academics whose findings did not conform to the approved ‘consensus’, lost their research grants. The acclaimed botanist David Bellamy is an example. Science, by its nature, is never settled.

Ask yourself this, Dave, when national borders and democratic accountability have been dissolved; when a one-world-government, tasked with saving the planet, has been established, what then will avert totalitarianism? When all, but the favoured elite and their private army, die of cold - or of heat; when humans are reduced to eating grass as in socialist Venezuela, or each other as they did under Stalin, where will your children hide?

We are the lucky survivors of two terrible and very recent world wars. The best of our nation fought and died to prevent two powerful socialist governments from expanding into the lives of people. When a government discovers that it has made a mess of its economy, it normally welcomes any diversion. Climate change - like acid rain, the ozone hole and global cooling - is a diversion. Ask yourself why a diversion is needed - and who will ultimately benefit. It won’t be the brave foot-soldiers. It never is.

Governments should concentrate on what their citizens elected them to do. It may be boring compared to strutting on the world stage - but it is their job. The planet can take care of itself.

Prof. Christine Wheeler McNulty