IT'S lovely to read our Susan Chapman writing again, (Letters 11th Feb - 'We must wake up and leave fossil fuel in the ground').

As far historically as one can go back in time the climate forcing gas, carbon dioxide, has been locked in step by step with the human population such that every one billion more humans increases the earth's CO2 levels by 20 parts per million which is fast enough to induce rapid climate warming changes which in turn releases a positive feedback of past locked-in climate change gases, methane and carbon dioxide, from ever-rising earth surface temperatures.

Whether or not humans then cut their emission rates, the time will come when it is too late to stop this positive feedback loop from the earth surface and temperatures will carry on rising until the entire reserve of earth's surface warming gas methane and carbon dioxide is freed into the atmosphere at which point life as we now know it will cease due to expanding and more turbulent sea levels as oceans warm and levels rise and increased wind velocities caused though larger variations between the equatorial and polar temperatures drive ever larger cyclonic conditions across the globe.

The point everybody avoids to mention is that it is the human population that drives CO2 levels that drive climate change and until someone somehow halts and reverses the human population trend then the fate of life on earth as we now know it will end.

No wonder NASA at present is rushing to create a Moon colony of human beings that could act as an 'Adam and Eve' backstop in the event that life on earth for the rest of us goes too pear shaped for survival.

DOUGLAS MILLS

Fraser Road, Poole