The globalized food industry relies heavily on inexpensive fossil fuels. Modern farm production is highly dependent on diesel-powered equipment; fertilizers are produced from natural gas and pesticides from oil. As the costs of these critical inputs rise, their use will decline, which will lower crop yields over time. (The increasing cost of North American natural gas has already caused almost half of U.S. fertilizer production to move offshore.) Corn and wheat, two staple crops, are particularly dependent on fertilizer and could experience significant declines. Impacts on diet and nutrition will be determined by the severity of the decline and which crops are most affected.
Some farmers will choose to leave farming as they struggle to maintain profitability. Reduced profitability also may increase pressures on farmers to sell their land for development. The result could be a combination of farm consolidation and reduction in acreage farmed.
Complicating factors such as drought years or fuel price spikes could lead to short- or medium-term food shortages. Long-term water availability may decline, in part due to the impacts of climate change. In extreme cases, farm acreage will go out of production due to a lack of water.
As transportation fuel costs rise, some farmers may choose to grow crops as feedstock for biofuel processing, leading to a reduction in acreage farmed for food. Like food crops, however, biofuel feedstock growers will face similar constraints on the cost and availability of inputs. As prices rise for both fuel and food, farmers will adjust crops accordingly.