Will charcoal save us all?

Well, it probably won't actually save us all, but charcoal (biochar as it is now called in trendy circles) is, according to the Economist, a new way to reduce global warming gases. From the article:

the latest fashion for dealing with global warming is to bring back charcoal. It has to be rebranded for modern consumers, of course, so it is now referred to as “biochar”. But there are those who think biochar may give humanity a new tool to attack the problem of global warming, by providing a convenient way of extracting CO₂ from the atmosphere, burying it and improving the quality of the soil on the way.

I'm not quite sure (and the article doesn't say) exactly how the carbon dioxide is removed from the atmosphere when charcoal is produced by burning, but I think the idea has many other merits. On improving the soil:

Most of the (Amazon) forest’s soil is heavily weathered and of poor quality. But the so-called “terra preta”, or “black earth”, is much more fertile. This soil is found at the sites of ancient settlements, but it does not appear to be an accidental consequence of settlement. Rather, it looks as though the remains of burned plants have been mixed into it deliberately.

The charcoal does not rot and provides a catalyst for limiting exhumation from the soil of nitrous oxide and methane and also appears to prevent fertilizing nutrients (nitrogen, phosphate, etc.) from leaching out.

And finally, on the prevention of soot from wood-burning stoves in the developing world:

Many (poor farmers) burn wood, waste and dung indoors for heating and cooking. The soot released into the air as a consequence is also a climate-changer because, being dark, it absorbs heat. Much worse, though, about 1.6m people are killed each year by inhaling it. But pyrolytic stoves produce almost no soot—the carbon is all locked into the biochar. Worldstove, a firm based in Italy, seeks to provide small and simple pyrolising stoves to poor countries.

I hope the pilot tests prove as exciting and possible as the initial experiments.