Last week’s blog post (Feeding the World) showed that farmers worldwide had, since 1950, quadrupled grain production. How is this possible? The answer is fertilizer; more specifically, nitrogen fertilizer. This graph shows global fertilizer use. In 1950, farmers applied less than 5 million tonnes of nitrogen (measured in terms of actual nutrient, not fertilizer product). In 2015, farmers applied more than 110 million tonnes. We managed to increase grain output fourfold largely by increasing nitrogen inputs 23-fold.
Nitrogen fertilizer is a fossil fuel product, made primarily from natural gas. One can think of a modern nitrogen fertilizer factory as having a large natural gas pipeline feeding into one end and a large pipe coming out the other carrying ammonia, a nitrogen-rich gas. To produce, transport, and apply one tonne of nitrogen fertilizer requires an amount of energy equal to almost two tonnes of gasoline. One reason we have been able to increase grain production fourfold since 1950, and human population threefold, is that we found a way to turn fossil fuels into plant nutrients into enlarged food supplies into us. With fertilizers, we can convert hydrocarbons into carbohydrates.
Dr. Vaclav Smil is an expert on the material flows, nutrient cycles, and energy transformations that underpin natural and human systems. He believes that without the capacity to turn fossil fuels into nitrogen fertilizers into enlarged harvests, nearly half the 7.4 billion people now on Earth could not be fed and could not exist. Smil calls factory-made nitrogen “the solution to one of the key limiting factors on the growth of modern civilization.” This blog highlights the many ways humans have managed to remove the limiting factors to the growth of modern civilization.
Finally, 1950 was long ago. Surely rapid increases in fertilizer consumption must have tapered off in recent years. That isn’t the case. Canadian consumption is rising especially rapidly. A look at Statistics Canada data (CANSIM 001-0069) reveals that Canadian nitrogen fertilizer consumption has increased 65 percent over the past decade (2006 to 2016). Like many countries, Canada is boosting food output by increasing the use of energy-intensive agricultural inputs.
Graph sources: Vaclav Smil, Enriching the Earth; UN FAO, FAOSTAT; International Fertilizer Industry Association, IFADATA; and Clark Gellings and Kelly Parmenter, “Energy Efficiency in Fertilizer Production and Use.”