Monbiot: Methane Findings Highlight the Scam of Carbon Trading

The Scam of Global Warming Is That We Pay Others For Our Complacency
The most destructive effect of the carbon offset trade is that it allows us to believe we can carry on polluting

George Monbiot, The Guardian (UK),  Jan. 22, 2006   

[A] study published  last week in Nature showed, to everyone's astonishment that plants produce methane, a greenhouse gas… But while this study does nothing to threaten global warming  theory … it should shake our  confidence in one of our favourite means of tackling it: paying other people to clear up the mess we've made.

Both through the unofficial carbon market and by means of a  provision of the Kyoto protocol called the “clean development  mechanism”, people, companies and states can claim to reduce their emissions by investing in carbon friendly projects in poorer countries. Among other schemes, you can earn carbon credits by paying people to plant trees. As the trees grow, they are supposed to absorb the carbon we release when we burn fossil fuels.

Despite the new findings, it still seems fair to say that forests are a net carbon sink, taking in more greenhouse gases than they release. If they are felled, the carbon in the trees and the soil they grow on is likely to enter the atmosphere.  So preserving them remains a good idea, for this and other reasons. But what the new study provides is yet more evidence that the accountancy behind many of the “carbon offset” schemes is flawed.

While they have a pretty good idea of how much carbon our factories and planes and cars are releasing, scientists are much less certain about the amount of carbon tree-planting will absorb. When you drain or clear the soil to plant trees, for example, you are likely to release some carbon, but it is hard to tell how much. Planting trees in one place might stunt trees elsewhere, as they could dry up a river that was feeding   a forest downstream. Or by protecting your forest against loggers, you might be driving them into another forest. As global temperatures rise, trees in many places will begin to die back, releasing the carbon they contain. Forest fires could wipe them out completely. The timing is also critical:  emissions saved today are far more valuable, in terms of reducing climate change, than emissions saved in 10 years' time, yet the trees you plant start absorbing carbon long after your factories released it. All this made the figures speculative, but the new findings, with their massive uncertainty range (plants, the researchers say, produce somewhere between 10% and 30% of the planet's methane) make an honest sum impossible.

In other words, you cannot reasonably claim to have swapped the carbon stored in oil or coal for carbon absorbed by trees.

Mineral carbon, while it remains in the ground, is stable and quantifiable. Biological carbon is labile and uncertain.  To add to the confusion, to show that you are really reducing atmospheric carbon by planting or protecting a forest, you must demonstrate that if you hadn't done it something else would have happened. Not only is this very difficult to do, it is also an invitation for a country or a company to threaten an increase in emissions. It can then present the alternative (doing what it would have done anyway) as an improvement on its destructive plans, and claim the difference as a carbon reduction.

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But perhaps the most destructive effect of the carbon offset trade is that it allows us to believe we can carry on polluting. The government can keep building roads and airports and we can keep flying to Thailand for our holidays, as long as we purchase absolution by giving a few quid to a tree-planting company.
© Guardian Newspapers Limited 2006


The theory is sound - planting more trees is (in general) a good thing - but you do have to be selective. The trees that are the worst culprits are fast-growing trees. The trees that are the best sinks are generally the slowst growing. Methane is also not the only gas to be concerned with - cerbon dioxide is also a problem. For that matter, so is water vapor. Again, different types of tree will affect these in different ways. Fast-growing, fast-living trees will pump a great deal of water out of the ground and rivers into the air. This is Bad News, because in the air is exactly where you don’t want the water. Finally, the colour of the leaves is also important. What you want is for vegetation to absorb a lot of heat during the day (increasing humidity and the liklihood of rain) and for that heat to be given up at night (a decent percentage of the heat will escape into space, where it is harmless).

You also want to pick and choose what to grow, based on the local ecosystem. Native plants to an area are generally a good idea. You also want the plants to be good for the soil. Certain combinations of vegetation will work better than others, so picking something that works well with other anti-greenhouse plantlife would seem an excellent step.

The problems arise when people opt for fast-growing, commercially farmable trees. Not only are such trees damaging all round, but by harvesting them in a few years you completely undo whatever good you did actally accomplish.

Well, that’s part of the problem. The other part of the problem is that South American countries are cutting down the Amazon rainforest (remember that bit about increased humidity? what do you think causes the rain in a rainforest?) at an incredible rate. An area almost twice the size of Belgium is either cut down or burned every single year - estimates have massively lept upwards after satellite photographs showed there had been a lot of very secretive illicit logging. The areas cut down are then used for farming, but because the soil is so poor, it is rapidly unusable and the farmers have to move into newly logged areas on a regular basis. It will be almost impossible to restore the forest, as the soil is incapable of supporting vegetation without the massive injections of nutrients supplied by normal forest decay.

Africa was once largely green and it is believed likely that the spread of deserts over historical timeframes has been a result of massive deforestation on a continental scale. In recent years, global warming has worsened the problem. (As you heat up the air, it holds onto the moisture it does have all the more. This reduces rainfall, so what little vegetation there is will die back, increasing the reflectivity of the ground, thus increasing air temperatures, thus locking the moisture in even more.)

So, the solution would seem to be in two parts. First, the right trees must be planted. No more of this opportunistic feel-good-but-do-bad stuff. We’ve also got to plant them in the right order of magnitude. If we’re planting one tree for every hundred thousand that is being cut down, we’re not going to make much of an impact - especially as deforestation was becoming a problem three or four thousand years ago. Replanting most of Africa, a large percent of Europe and a good portion of the Americas goes a little beyond planting a couple of trees next to a coal-fired power station.

If we want to tackle the problem, then we’ve got to tackle the problem on the scale of the problem. It won’t be cheap, it won’t have any resale value, but it would have the advantage of actually working.