Re: Letters to Science in response to the paper by Tim Searchinger of Princeton and R. A. Houghton of Woods Hole et. all. in February.   It surprised the scientific world by documenting the oversights in calculating the environmental impacts of bio-fuels.

Biofuel production consumes food resources and produce added CO2.   It happens by causing the conversion of productive ecologies into farms.    These letters clarify some of the issues that were left unclear in their paper, but still leave big things out]

Letter to Science,

The 10/17/08 letters in Science by Vinod Khosla and reply by Tim Searchinger and R. A. Houghton do clarify some to the complicated measurement problems regarding the environmental impacts of bio-fuels on food production. Both seem to miss the largest of the growing strains on the food production resources of the earth. The real culprits are urbanization and economic growth, of course.

Both are ‘inexorably’ increasing food demand at increasing rates, as well as depleting or converting food and fuel production resources to other use. One of the feedbacks is that these both provide the market for high priced bio-fuels. Bio-fuels helps them expand and so also to promote growing demand for bio-fuels.

The way markets consume resources they use the best resources first and then less productive ones, as we’re now finding necessary. To make more marginal ones profitable prices need to rise.

That natural increasing use of less productive resources (diminishing returns) has the effect of transferring food resources from poor to rich. Of course, the other important feedback is that, whatever the source, simply increasing energy availability for economic growth and urbanization also increases all their other companion impacts at the same time.

The point is not just to draw attention to the role of the markets driving the conversion of agricultural and forest land to other uses. It’s also that, almost universally, scientists are not looking at the relatively easily predicted limits of our own solutions.

If we make global system plans we need to look at the whole physical system they’re part of, or they won’t work. We could “borrow another earth” perhaps, or figure out how some better way than Malthus did to reduce our growing demand.

There seem to be lots of interesting complex natural systems that accommodate limits gracefully. The similarities between our unplanned complex systems and nature’s could be studied for useful hints.

pfh