Food Production May Exceed Greenhouse Gas Emission Targets by 2050

If we want to reduce climate change, we may want to focus on our diets a little bit more. Scientists have found that if current trends continue, food production alone will reach, if not exceed, global targets for total greenhouse gas (GHG) emissions in 2050

The food we choose to eat has an enormous environmental impact. Meat-heavy diets in particular can cause an increase in greenhouse gas emissions. As the world's population increases, it's likely that diets with a taste for meat will not meet projected food demands of what is expected to be 9.6 billion people in 2010.

The scientists examined land use, land suitability and agricultural biomass data. With this information, they created a model that compared different scenarios for 2050, including scenarios based on maintaining current trends.

"There are basic laws of biophysics that we cannot evade," said Bojana Bajzelj, the lead researcher of the new study, in a news release. "The average efficiency of livestock converting plant feed to meat is less than 3 percent, and as we eat more meat, more arable cultivation is turned over to producing feedstock for animals that provide meat for humans. The losses at each stage are large, and as humans globally eat more and more meat, conversion from plants to food becomes less and less efficient, driving agricultural expansion and land cover conversion, and releasing more greenhouse gases. Agricultural practices are not necessarily at fault here-but our choice of food is."

The researchers found that if we maintain our "business-as-usual" policy, by 2050 cropland will have expanded by 42 percent and fertilizer use will have increased by 45 percent over 2009 levels. In addition, a further tenth of the world's tropical forests would disappear over the next 35 years.

"It is imperative to find ways to achieve global food security without expanding crop or pastureland," said Bajzelj. "Food production is a main driver of biodiversity loss and a large contributor to climate change and pollution, so our food choices matter."

The findings are published in the journal Nature Climate Change.