Irrigation and fresh water will be required in increasing amounts to support the expansion of global agriculture. Groundwater is becoming more difficult and expensive to pump in many areas, and is non-existent in others. Currently major portions of California and Texas are in severe drought. Desalination of seawater is very energy intensive and generally is not economic for agriculture use.
Energy is becoming a more expensive input. When diesel fuel and fertilizer costs increase substantially growers reduce planting reflecting the economics. The volatility of energy and fertilizer prices also make it very difficult to plan what crops to plant, and in what quantities. When energy prices increase agricultural prices must increase substantially or economics will dictate fewer acres are planted. Many parts of the globe cannot afford expensive grains.
Asian population and economic growth will result in more people eating increasingly energy intensive foods as they “Westernize” their diets. Demand for grains should increase as grains are increasingly used as a biofuel or animal feedstock.
A crop failure in North America would have severe implications for global grain prices. The U.S. and Canada are the major global grain exporting countries. An early freeze in the grain belt, or a disease such as UG-99 (a wheat stem rust now threatening India), could severely impact crop yields. The U.S. experienced a major wheat crop failure due to disease back in the 1950’s; a repeat would be much more disruptive.
Historical trends in the Midwest indicate a severe drought occurs every 20 years or so (tree rings indicate this cycle has persisted for 600 years) – and it has been roughly 20 years since the last major drought. Some meteorologist also suggest a correlation between the sunspot cycle, the sun’s energy that reaches the earth, and long term weather trends – claiming the lack of sunspots can cause global cooling.
The “Maunder” and “Dalton” sunspot minimums correlated with the “Little Ice Age” of roughly 1650-1800. Global cooling trend would adversely impact growing seasons. The current sunspot cycle should have recovered from a low point of activity and resulted in dozens of sunspots by now – yet sunspots are eerily missing, and have been for about a year now. Scientists are unsure why this has occurred.
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Edited by stocks, 15 September 2009 - 09:33 AM.