Remember Malthus? He is the man whose ideas have been the inspiration since 1798 for anyone concerned about over population and food scarcity. Relegated to history’s back shelf in the 1960s by agriculture’s Green Revolution, his forecasts are back, with a vengeance. Now, in addition to food shortages, we also have scarce fresh water, top soil, crude oil, etc.

Thomas Robert Malthus was the English economist whose 1798 publication, An Essay on the Principle of Population, caused Thomas Carlyle to dub economics as the ‘dismal science’. The principle theme of the essay is that “the power of population is indefinitely greater than the power in the earth to produce subsistence for man.”

An honors graduate in mathematics from Cambridge, Malthus argued that the human sex drive can produce geometric increases in population per the series 1, 2, 4, 8, 16. At the same time, the earth can at best increase food production at an arithmetic rate, as 1,2,3,4,5. Malthus stated that the earth’s population must remain within resource limits, either by using human generated “preventive checks” which lower the birth rate, or with nature imposed “positive misery checks” which increase the death rate.

A devout Christian, Malthus abhorred such preventive measures as contraception and abortion. He argued instead for delayed marriage through moral restraint. He opposed the Poor Laws, England’s first real attempt at welfare, because their support encouraged earlier marriage and procreation.

Despite his warnings, the world’s population has grown by six times since 1800, limited periodically by the positive misery checks of hunger, disease, and war. In the mid-20th Century, the Green Revolution arrived in world agriculture, founded on cheap fossil fuels which powered mechanized industrial farms. They use vast amounts of petroleum based pesticides and fertilizers in lieu of manure and crop rotation. These often irrigated farms produced major gains in cereal crop yields. The end of world hunger seemed in sight.

The Wall Street Journal mocked both England’s Prince Charles and Al Gore as “Prince Malthus” and “Senator Malthus” for their concerns about population growth, the environment, and resource scarcity. Technology and hydrocarbons had apparently sidelined the dismal science.

But in the 21st Century, fossil fuel’s supply is tightening, and it is no longer cheap. Pesticide resistant bugs flourish; top soils erode from aggressive tilling; declining yields from single crop agriculture demand more fertilizer; ground water tables lower; and the Green Revolution has begun to gray. But world population continues its yearly addition of seventy millions. In parts of the world, nature is implementing Malthus’ most serious positive misery check. As he put it, “Famine seems to be the last, the most dreadful resource of nature.”

With his math skills, Malthus might well have forecasted the seventy million people that the world adds each year at its dinner tables. He could not have known that seven hundred million personal cars and trucks would also join the food line by consuming biofuels. If he had, his essay would have been even more dismal. Recent record prices for grains are the result of competition for the same cropland between people and biofuels. To feed continuous E-85 ethanol fuel to one average car or light truck requires allocating the harvest from 2 acres of Midwest corn land.

No problem, say our leaders. We can use cellulose from crop residue like corn stover, the stalks and leaves. But scooping those up to make ethanol exposes the soil to erosion from wind and water. It also deprives the soil of nutrients, requiring more natural gas based fertilizers. Every ton of corn stover contains approximately ten pounds of nitrogen, two pounds of phosphorous, and forty five pounds of potassium. Dealing with the growing scarcity of arable land and transportation fuel will require both conservation and major life style changes, enforced by strong measures like unpopular carbon taxes.

We do have a few political leaders with political courage such as Congressman Oberstar whose leadership of the House Transportation Committee is supporting energy efficient electric rail. Unfortunately, overall, political courage is another commodity that is in short supply.

Rolf E. Westgard is a professional member of the Geological Society of America.