White is the new black. Actually, white is also the new blue, grey and brown. White is everything – white clothes, shoes, furniture, houses, roads, flowers, trees, grass and, most important of all, big white hats with very wide brims. White is the cool colour for the summer, and the autumn, and the winter. In fact, white is for ever. It’s fun, it’s stylish and it saves the human species.

This new and exciting fashion wave is called albedo chic. Albedo – not a word previously heard on the catwalks – is a measure of reflectivity. Fresh snow has an albedo of about 90%, meaning it reflects back 90% of the light that hits it. The Earth as a whole has an albedo of about 30%. This is far too low if we keep heating the planet by increasing the number of humans and pumping 27 billion tons of carbon dioxide into the atmosphere every year. So wear white – it increases our albedo and cools the planet. Oh, and eating lettuce will be desperately unchic. (I’ll explain later.)

Well, of course, it won’t work. Invented half-jokingly by the physicist and SF writer Gregory Benford, albedo chic is really only a thought experiment designed to dramatise our predicament. That predicament is the destruction of the environment that sustains us, of our only home, by human activity. Anthropogenic (human-caused) global warming is real, it is happening and it is now too late to do anything about its impact over the next 30 years. Global temperatures will rise by 1.5 to 2 degrees Celsius. There will be as yet unimaginable devastation through flooding, changes in weather patterns, desertification and uprooting of entire populations. We will survive, but what then?

If we do nothing, then the temperature rise could be 5 degrees within a century, at which point the survival of our species will be in the balance. Perhaps it is too late even to prevent this. We can already do nothing whatsoever, according to James Lovelock, the great British deep-green: “Save the planet? We can’t save the planet – we never could.”

Lovelock invented the Gaia concept, an idea that created the discipline known as Earth systems science. Named after the Greek goddess of the Earth, this sees the planet as a single living organism. In the eyes of 4-billion-year-old Gaia, humans are just a brief but very irritating episode. We shall be destroyed by our own dirty habits. Gaia will live on.

For Lovelock, our only faint hope of survival is “sustainable retreat”. No further economic or population growth is possible. Indeed, we are past the point of no return and the likely fate of the species is tribal subsistence in the Arctic basin, the last place on Earth cool enough to sustain us. All we can do now is preserve what we can of human civilisation.

Few doubt that possibility – sceptics of anthropogenic global warming are now very few and far between – but the scientific consensus is that, though the climatic history of the next 30 years is more or less written, something can be done in the long term to keep us roughly in the style to which we have become accustomed, long-lived, rich and populous. Nobody, however, thinks it will be easy, technically or politically. We have to act soon, we have to think big and we have to work together. Humans are bad at all of those things, especially the last. And the window of opportunity is closing very quickly indeed. We probably have less than a decade to get it right. What, then, must we do?

Answers to this question fall on either side of a deep conceptual divide that shows few signs of being bridged. The divide is deep because it lies between two conflicting views of how humans should relate to nature. On one side is the conventional green lobby – people like Sir Jonathon Porritt and Zac Goldsmith – that believes in weaving ourselves more deeply into the natural world through the use of sustainable energy sources like wind, waves and biofuels. Let us call them the Sandals. On the other side are deep, less conventional greens like Jesse Ausubel in America and Lovelock in Britain, who believe that we should, in Ausubel’s words, “decouple our goods from demands on planetary resources”. For the latter, nuclear power and carbon-scrubbed natural gas, combined with low-energy transport and urban systems and a massive shrinkage in agriculture, are the only answer. We should not tie ourselves more tightly into nature, we should liberate it from our destructive powers. Large parts of the Earth should be returned to the embrace of Gaia. Let us call these greens the Nukes.

Currently the Sandals and the Nukes clash most obviously over nuclear power versus sustainable power sources. With Blair’s recent endorsement of nuclear, the Nukes seem to be winning. Meanwhile, George Bush’s acceptance of America’s addiction to oil and the realisation of the strategic weakness of depending on Middle Eastern oil are turning even the most hardened neocons into born-again greens. Billions of dollars of investment are now waiting to be plunged into the most promising technologies. It is still too early to say what they will be. The Americans are naturally Nukish, favouring high-technology solutions; the Europeans tend to be Sandalish, favouring sustainables. In the long term, this conceptual divide will have to be bridged – perhaps, as some economists have suggested, through a combined approach using the best ideas from both sides.

But at least there are some necessary goals on which we can all agree. The big, glaringly obvious goal is reducing atmospheric carbon. Carbon has been locked in the Earth for billions of years. We have always unlocked some of it by turning it into carbon-dioxide gas through burning. But, since industrialisation began in the 18th century, we have begun to burn coal and oil – so-called fossil fuels – on an increasingly massive scale.

Now we chuck a mountain into the air every year. If we solidified the 27 billion tons of carbon dioxide (over 6 billion tons of pure carbon) produced by humans annually, it would make a mountain a mile high and 12 miles in circumference. As a result, the Earth’s atmosphere now contains about 380 parts per million of carbon, compared with about 280 parts, which seems to have been the default setting that made our existence possible. This traps heat and causes temperatures to rise. If we are to survive, we have no choice but to stop chucking mountains. The favoured method is carbon sequestration – essentially capturing the carbon produced by human activity and putting it anywhere but in the atmosphere. We know how to do this; we just don’t know if we can do it on a big enough scale, nor whether the carbon will stay sequestered.

In the North Sea’s Sleipner field, the Norwegian state oil company, Statoil, is already trying the obvious method: putting the carbon dioxide back into the Earth whence it came. A million tons annually are being pumped from the Sleipner platform into the Utsira formation beneath the sea bed. A huge bubble will be formed which has to be carefully monitored for leaks. The prospects are good, as we do know that gas had lain trapped in such saline aquifers for millions of years without leakage.

More radical, however, are BP’s $600m plans for the North Sea’s Miller field. The company plans to extract gas from the field and then split it into hydrogen and carbon dioxide. The hydrogen would be used to fuel a power station at Peterhead, Scotland. Hydrogen is an absolutely clean fuel, water being its only waste product. The carbon dioxide, meanwhile, would be pumped back underground into oil reservoirs. This would force out more difficult-to-recover oil and lock away the carbon dioxide.
All of which is promising, but is only a very small step. We have no idea whether there are enough aquifers beneath sea beds to sequester billions of tons of gas. One alternative is to sink the gas into the deep ocean. Below 3,000 metres, it would be solidified by pressure and cold.