Being overweight, even fat, can be a problem.

We know what to do about it – that’s eat less and exercise more – but it’s easier said than done. Watching the television and snacking is much more appealing, although the consequence is that we pile on the pounds and the problem becomes harder and so more difficult to deal with. Appropriately, this chain of events can be described as a feedback – negative in this case.

From a climate change point of view, we are stuffing our planet with fossil fuel-flavoured carbon dioxide, because it’s easy, and supposedly cheap, and indulging ourselves with the comfort of 4x4s, cheap flights and air conditioning.

If we could see into the future, we would be horrified by the number of resulting negative feedbacks that are guaranteed to make life difficult, or even impossible, for our descendants.

A case in point is the Arctic. Ice and snow are light coloured and so reflect up to 80 per cent of the incoming heat from the sun, while it’s the other way round with the dark-coloured sea once the ice has melted. The Arctic is now warming four times as fast as the rest of the planet, and so more ice melts and more water is exposed and more warming results, so more ice melts, and… that’s negative feedback.

It follows from this that the methane trapped in the cold seabed and the permanently-frozen ground will be released, making the climate even warmer, so more escapes, and… more negative feedback.

Another example, thank goodness, is the way that half the CO2 produced from fossil fuels is absorbed by the oceans, rather than staying in the atmosphere to make it warmer.

However, CO2 is more soluble in cold water and so as the seas warm up, as they are doing, they absorb less CO2, so more remains in the air, trapping more heat, and so the seas get even warmer and can hold even less CO2, and… another negative feedback.

Whatever we do seems to produce more CO2, making it more likely that the climate will get warmer. Seven billion humans have removed half the world’s trees, and the remaining rain forest is shrinking by the day. The result is fewer trees to capture and store CO2, and those that are burned release extra CO2 to the atmosphere, so it gets hotter, forest fires are more likely resulting in even fewer trees, and so… more negative feedback.

We need to be mindful of the consequences of the way we behave and not lose control of the future – it’s not ours, we have only borrowed it from our grandchildren, and mine are not pleased.