Producing and cooking food contributes around 30% of carbon emissions worldwide, which is more than the emissions from personal travel, lighting and heating and air conditioning combined, according to researchers. If unchecked, by 2050, emissions from food production alone, would reach or exceed international targets for total greenhouse gas emissions.
Experts say humanity needs to radically alter the way it produces and consumes food – especially to reach a goal of holding the rise in earth’s average temperature to below 2C, as cited by Christian Science Monitor staff writer Cristina Maza in an article earlier this month.
Some environmentalists say a vital piece of the answer must be agricultural methods that are less carbon-intensive – and changing dietary habits in the same direction. “We need to convert more crop production to organic and ecological,” says Kendra Klein, staff scientist and agro-ecology expert at Friends of the Earth, an environmental organisation, while stressing that the most important thing is reducing meat consumption.
Fertiliser use releases large amounts of nitrous oxide, while manure from livestock releases methane, a gas that heats the planet around 80 times faster than carbon dioxide. Livestock production is responsible for around half of all carbon emissions from the agriculture, forestry, and land-use sectors. In fact, a third of the crops grown worldwide are fed to animals to produce meat, a system experts say is highly inefficient.
Food waste is a major contributor to carbon emissions, particularly in the United States and Europe. The Food and Agricultural Organisation estimates that around a third of all food produced for human consumption is wasted. If less food is wasted, less will need to be grown. Research released recently concluded that food waste alone is responsible for around 3.3 gigatonnes of carbon emissions.
As the world’s population continues to grow, so will demand for food. Over the past decade, food demand spurred the global expansion of farmland by around 10mn hectares a year, according to research published in the journal Nature Communications. In many places trees and rainforests were razed to make space for crop and livestock production, reducing the earth’s ability to absorb carbon dioxide.
Experts feel the current food production methods are, by and large, unsustainable as they create significant environmental costs via greenhouse gas emissions and other routes.
More consumers, in some parts of the world, are taking seriously the idea of cutting back on meat consumption for environmental reasons.  A report released by the US National Academy of Sciences in February, concluded that humans could reduce food-related greenhouse gas emissions by around 70% by switching to a plant-based diet.
Research shows that organic production cuts carbon emissions per acre by 50% or more, compared with conventional farming. Creating synthetic fertiliser is energy intensive and emits a lot of greenhouse gas. Pesticide-free soil, on the other hand, holds more carbon and thus provides more opportunities for carbon sequestration.