Carbon Eating Trees

Growing more plants - and improving breeds to grow faster and live longer - is integral to solving the carbon problem.

Climate Wire reports (registration required) a new study by Oregon State University researchers that suggests that Pacific Northwest forests if carefully managed could store 46% more carbon than they now do. Growing more plants - and improving breeds to grow faster and live longer - is as integral to solving the carbon problem as curtailing emissions. Here for those new to this topic is Freeman Dyson's classic statement of the problem in the New York Review of Books:

About 8 percent of the carbon dioxide in the atmosphere is absorbed by vegetation and returned to the atmosphere every year. This means that the average lifetime of a molecule of carbon dioxide in the atmosphere, before it is captured by vegetation and afterward released, is about twelve years. This fact, that the exchange of carbon between atmosphere and vegetation is rapid, is of fundamental importance to the long-range future of global warming....

If we can control what the plants do with the carbon, the fate of the carbon in the atmosphere is in our hands. That is what Nordhaus meant when he mentioned "genetically engineered carbon-eating trees" as a low-cost backstop to global warming. The science and technology of genetic engineering are not yet ripe for large-scale use. We do not understand the language of the genome well enough to read and write it fluently. But the science is advancing rapidly, and the technology of reading and writing genomes is advancing even more rapidly. I consider it likely that we shall have "genetically engineered carbon-eating trees" within twenty years, and almost certainly within fifty years.

Carbon-eating trees could convert most of the carbon that they absorb from the atmosphere into some chemically stable form and bury it underground. Or they could convert the carbon into liquid fuels and other useful chemicals. Biotechnology is enormously powerful, capable of burying or transforming any molecule of carbon dioxide that comes into its grasp. Keeling's wiggles prove that a big fraction of the carbon dioxide in the atmosphere comes within the grasp of biotechnology every decade. If one quarter of the world's forests were replanted with carbon-eating varieties of the same species, the forests would be preserved as ecological resources and as habitats for wildlife, and the carbon dioxide in the atmosphere would be reduced by half in about fifty years.

The policy implications? Forestry management has to be thought of as part of our carbon management policy. Federal scientific dollars should be allocated to biological research of the kind Dyson describes. And let's hope that President Obama does not allow next Arbor Day to proceed without a well-publicized presidential tree-planting.