Now that the climate change sceptics have weighed in heavily at Copenhagen, perhaps we should take some time out to consider one of the basics involved here. Photosynthesis: converting the sun's power, light and warmth - to energy.

All animals make - transpire - huge quantities of carbon dioxide. The earth's vegetation "breathes" this in and then transpires not just oxygen but oxygen and a little hydrogen - separately and severally, oxygen and water - into the atmosphere.

Back in 1772, John Priestley, a British chemist, proved that plants breathe as they grow. He enclosed a growing plant in a sealed airtight container, and found that it died of suffocation, just as surely as any animal would have done.

And quickly, too. That was a start. But then he put a growing plant and an animal in a similar container and found that both could live in the environment they mutually created. At the time it seemed a miracle but was proved to be the result of the exchange of chemically different kinds of "breaths" or gases shortly after to be named oxygen and carbon dioxide. The animal inhaling oxygen O2 and exhaling carbon dioxide CO2 - and the plant doing just the opposite. This was the first realisation of the process of photosynthesis; perhaps the most massive chemical process on earth. And it is the fundamental process of life.

Apart from the unremitting and wanton emission of green house gases - and increasing dramatically in recent times - the human race itself is generating, and transpiring, an ever-increasing volume of carbon dioxide into the atmosphere.

And yet we systematically continue to denude Mother Earth of the great forests, carelessly ignoring one of the two parts of the essential equation, if you like, of life.

We must keep these two parts of the equation in balance.

Planting trees, halting deforestation, conserving the forests we have; all absolutely essential to the fragile life on the surface of the planet.

More carbon dioxide dictates the need for more vegetation - more reafforestation. Further denuding of the forests must be halted, and conservation and reafforestation should begin immediately.

The conference at Copenhagen is not barking up the wrong tree but - perhaps - overlooking the most fundamental of natural chemical processes affecting the world's climate change. We must act now!