What has the carbon atom done for us?

In the film the Life of Brian, Reg, leader of the revolutionary People’s Front of Judea, asks the question ‘What have the Romans done for us?’ To listen to some discussions ahead of the forthcoming COP-26 climate meeting in Glasgow in November, a modern re-run might ask ‘What has carbon done for us?’

The poor atom, if it could actually speak, might justifiably ask to be given some slack. It could quietly point out that all organic life is essentially built using its unique atomic architecture - without it, we would simply not exist. Moreover, it is a particularly flexible element, existing in forms from hard diamonds to soft graphite.

Its many compounds, formed with other elements, are ubiquitous - in the food we eat, the clothes we wear, and the fuels we use to heat our homes or to transport us around the globe. One of those compounds, carbon dioxide, provides us with a unique natural duvet in the atmosphere, without which we would all quickly shiver to death.

So, the short answer to Reg’s revised question is ‘quite a lot’.

The problem is not carbon, but in understanding the earth’s carbon cycles and then learning to live with nature’s rhythms in sustainable ways. The carbon on earth today was a gift forged and bequeathed to us in deep space-time by some distant, dying star. We’re still not exactly sure how it got here – perhaps delivered by solar winds or maybe we went bump in the night with another planet as the postman.

It is simple physics that this unsustainable rise in carbon concentrations in the atmosphere leads to planetary warming, adding unnatural heat to our natural climate duvet.

Whatever way carbon reached us, our planet is a closed system. The amount of carbon in this system does not change. However, at least since Heraclitus, we have understood that everything is permanently in a state of movement. Carbon is no different. Its cycles are nature’s way of transporting carbon atoms between reservoirs in the air, land and sea. The arithmetic is clear - all movement that shifts carbon out of one reservoir puts more into the others, leaving the total unchanged.

A ‘slow’ carbon cycle moves carbon between the air, rocks, oceans and then back to the atmosphere, starting with carbonic acid falling from the sky in rainfall, and ending with erupting volcanoes pouring carbon back into the air, hundreds of millions of years later. A ‘fast’ carbon cycle is based on photosynthesis and respiration. Plantlife takes carbon dioxide from the air, using it to convert energy from the sun to form sugars, ultimately allowing all life to thrive. The carbon is then released back to the atmosphere or into the soil and oceans through death and decay. A chunk of this buried carbon forms fossil fuels – stores of old chemical energy built up over geological time spans.

Left to their own devices, the slow and fast carbon cycles maintain a relatively steady concentration of carbon in the atmospheric reservoir, with the oceans playing a critical role in regulating any imbalance. Without human interference, the carbon in fossil fuels would leak back to the atmosphere through the slow carbon cycle. However, since the Industrial Revolution, we are accelerating that process – pumping millions of years of accumulated carbon reserves back into the atmosphere in the matter of less than a couple of centuries through the combustion of fossil fuels and rampant land destruction.

It is simple physics that this unsustainable rise in carbon concentrations in the atmosphere leads to planetary warming, adding unnatural heat to our natural climate duvet. We need to stop this ‘dumbest experiment in history’, to quote Elon Musk. We have no need to plunder the past – in a single hour, the amount of energy the earth receives from the sun is more than the entire amount the world consumes in a year. We need to learn to harness the constant flow of solar energy, rather than resort to ancient fuel stocks that are best left to cycle naturally.

More generally, we must solve this and other environmental problems quickly, or else, quite frankly, we’re toast – with nature having the last laugh at our environmental folly.