
Threats of Peak Oil to the Global Food Supply
Date: Sunday, July 03, 2005 @ 18:48:25 UTC Topic: General
by Richard Heinberg (A paper presented at the FEASTA Conference, "What Will We Eat as the Oil Runs Out?", June 23-25, 2005, Dublin Ireland)
Food is energy. And it takes energy to get food. These two facts, taken together, have always established the biological limits to the human population and always will.
The same is true for every other species: food must yield more energy to the eater than is needed in order to acquire the food. Woe to the fox who expends more energy chasing rabbits than he can get from eating the rabbits he catches. If this energy balance remains negative for too long, death results; for an entire species, the outcome is a die-off event, perhaps leading even to extinction...
...In 1909, two German chemists named Fritz Haber and Carl Bosch invented a process to synthesize ammonia from atmospheric nitrogen and the hydrogen in fossil fuels. The process initially used coal as a feedstock, though later it was adapted to use natural gas. After the end of the Great War, nation after nation began building Haber-Bosch plants; today the process produces 150 million tons of ammonia-based fertilizer per year, equaling the total amount of available nitrogen introduced annually by all natural sources combined...
...In the 1890s, roughly one quarter of US cropland had to be set aside for the growing of grain to feed horses - most of which worked on farms. The internal combustion engine provided a new kind of horsepower not dependent on horses at all, and thereby increased the amount of arable land available to feed humans.
Chemists developed synthetic pesticides and herbicides in increasing varieties after WWII, using knowledge pioneered in laboratories that had worked to perfect explosives and other chemical warfare agents. Pesticides not only increased crop yields in North America, Europe, and Australia, but also reduced the prevalence of insect-borne diseases like malaria...
...The end result of chemical fertilizers, plus powered farm machinery, plus increased scope of transportation and trade, was not just a three-fold leap in crop yields, but a similar explosion of human population, which has grown five-fold since dawn of industrial revolution....
Agriculture at a Crossroads
All of this would be well and good if it were sustainable, but, if it proves not to be, then a temporary exuberance of the human species will have been purchased by an eventual, unprecedented human die-off. So how long can the present regime be sustained? Let us briefly survey some of the current trends in global food production and how they are related to the increased use of inexpensive fossil fuels...
Read the whole article here: http://www.museletter.com/archive/159.html
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