Last year scientists at Cornell and elsewhere announced that they may have found a new weapon against climate change — in the soils of the Amazon Basin.
Amazon peoples thousands of years ago ploughed charred plants into the ground, perhaps to improve soil fertility or just as an ancient means of waste disposal.
Plants suck carbon out of the air as they grow and charring them keeps most of that stored carbon in a solid form which can be buried. What scientists found interesting was that the ancient Amazon ”biochar” soils still contained up to 70 times more carbon than the surrounding ground. And so the idea was born of how to trap carbon dioxide and stop it from reaching the atmosphere and cooking the planet. The notion of ploughing into the soil charred organic waste including food, woodchips, straw etc drew favourable reviews in the media .
Perhaps predictably, the biochar backlash swiftly followed. The anti-lobby feared that the private sector would bend biochar support to char whole forests, all in the name of stopping global warming, but really just to cash in on carbon credits or whatever other payments emerged. Among critics, British environmentalist George Montbiot wrote that “the last mass fuel cure, biochar, does not stand up.”
For me this has highlighted growing suspicion of private sector solutions to fighting climate change. The argument runs that industry created the problem of climate change, aided by consumer demand, through large scale combustion of fossil fuels, so don’t trust the private sector to solve the problem with market solutions like carbon trading or green certificates or other subsidies. Instead, carbon should be regulated through tough emissions caps, for example. The case of carbon markets has borne suspicion out to some extent. 
For example steel lobbies and power companies have earned multi-billion dollar windfalls under the European Union’s emissions trading scheme, a scheme meant to curb emissions from those two high-carbon sectors especially, Reuters analysis has showed.
Ambitious estimates by the International Biochar Initiative of the merits of the technology may have helped sow the seeds of the backlash. The IBI says biochar could remove 1 billion tonnes of carbon annually by mid-century. That’s more than one tenth of annual carbon emissions now. The trouble is uncertainty in how those numbers are calculated. Certainly, the IBI acknowledges its figures depend on a few “optimistic plus” assumptions.
The IBI says its estimates require charring of no more than 3.2% of the planet’s entire net production of energy from plants and trees, on farms or in the wild. That still sounds like quite a lot to me…
The problem of using plants to fight climate change was well debated two years ago in the case of biofuels, a new car fuel now blamed for hiking food prices by competing with crop production. The trouble is you can’t tackle a problem as big as climate without making mistakes and losing a few dollars.
Big claims for solutions may best be avoided for now.
(Pictures: top left – Brazilian farm workers burn off felled trees and brush in the typical slash-and-burn method of converting jungle into farm land, near the northern town of Acailandia in the Amazon Basin, some 1,600 kilometers north of Brasilia, September 22, 2003. By Rickey Rogers
Right – The sun sets over the Amazon port of Abaetetuba, near the river’s mouth, September 26, 2008. Picture taken September 26. By Paulo Santos)
