Environmental entropy

THAT biomass can be an antidote against global warming is an optimistic proposition. It seems unlikely that afforestation can keep pace with the rate of pollution of the atmosphere. Even if it did, it appears inconceivable that enough land would be available to grow trees to absorb sufficient volumes of carbon emitted into the atmosphere. Growing trees is the lowest-cost means to absorb carbon, and it must be distributed in an equitable manner over the entire world.

Can mechanisms be found to persuade nations to lower the carbon in the air to safe levels? The author marshals enough evidence for the proposition to be taken dead seriously. Warnings of dangerous consequences of rising levels of carbon in the air have already been sent out. Chloroflourocarbon (CFC) gases, the subject of the Montreal Convention, have already punched in the atmosphere over Antarctica.

Not enough is known about the climatic cycle to arrive at safe conclusions about the ultimate consequence of the rocketing levels of greenhouse gases. Nature maintains its various elements in dynamic balance, and there is a benign equilibrium between land and sea, plants and humans. And nature uses built-in mechanisms to rectify crucial imbalances. A few secrets of this complex elemental interplay are now understood, but a lot more remains a mystery.

Read works on the pragmatic assumption that pollution can not be lowered to desirable levels by just controlling emissions. It is in the nature of economic activity to continue to grow, and with it the consumption of energy. The way to handle greenhouse gases, says Read, is growing more trees to absorb more carbon.

To accelerate the growth of trees, an ancient silvicultural technology called "coppicing" is recommended. Very simply, a coppice is a bunch of trees that is cropped down to the stems on a regular cycle. The coppicing process leads to rapid growth since "new shoots are forced by the large rockstock in the ground". It is possible to grow 20 tonnes of biomass per hectare in the world's temperate zones, compared to 4 to 10 tonnes through conventional forestry. And now, biotechnology comes as a gift: it can increase productivity megafold when used in forestry.

Over decades, fossil fuels have proved their commercial viability. On the other hand, Read argues, biomass looks good when the costs of environmental preservation are considered. Biomass can not only be a source of energy but can also absorb carbon in the air.

The author also dispels the notion that land requirements for growing biomass will exceed availability. He estimates that 600 million ha will have to be allocated for forests to absorb the carbon necessary to prevent global warming. The problem is that this is about as much forest as has been lost since World War II. Existing practices of land utilisation are far from ideal since the costs of agricultural production in Europe, Japan and Korea are much above the costs in the rest of the world. There are regions in Africa where extensive degradation of land has taken place over the years. The reduction of inefficient agricultural production and reclamation of degraded land will provide enough space to grow more trees.

As for the mechanisms for reducing carbon levels in the air, the author suggests a Tradeable Net Absorption Obligation, under which a party can be penalised for exceeding emission limits. In fact, it makes economic sense for countries to reduce carbon levels by whittled down emission levels. As it is, t he developed countries have exhausted the cheaper options of emission reduction and will find absorption more economical. He makes a provocative suggestion that incentives for adopting "new renewable technologies" will be created when biomass production becomes too costly.

The book presents a plausible case for promoting biomass as means of controlling global warming. It anticipates and takes pains to clear doubts that are likely to arise with such a proposal. Although, at the outset, the idea smacks of hardline environmentalism, the author accepts economic compulsions in environmental preservation. As an engineer-economist, the author is sensitive to the scientific aspects of the problem and not indifferent to the political realities in which his ideas must be rooted.

---Kishore Jethanandani is a freelance writer.