Whether you’re counting by calories, kilograms, or monetary pounds, the world is wasting a huge amount of food. But there’s also another way to measure it: The quantity of resources we burn up for nothing at all.
The UN estimates that growing our food accounts for about 5 billion (and climbing) metric tons a year of carbon emissions; that’s about one fifth of the global carbon emissions. Within that number, you can also break it down into smaller sections: How much comes from ranching, or how much comes from Uruguay, for example. What hasn’t been broken out until now, though is how much carbon we’re releasing for food no one is eating. Researchers from Germany’s Potsdam Institute for Climate Impact Research have a study out in Environmental Science and Technology that answers that question.
Wasted food accounts for one tenth of all agricultural carbon emissions today, they say—and the projections for what that will look like in the coming decades are even worse both in terms of food wasted and carbon emissions.
“During the last 50 years, global average food waste per person has increased from 310 calories a day to 510 calories a day. The food waste problem is increasing in the recent decades,” study co-author Prajal Pradhan told Gizmodo. “If the current trend continues, GHG emissions associated with food waste will increase by 4-5 times between 2010 and 2050.”
Pradhan attributes part of that rise to to the higher proportion of wasted food overall, but also to changes in our diets themselves and a global shift towards eating more meat. “Diet changes towards a larger share of animal products could over-proportionally increase greenhouse gas emissions associated with food waste because animal products have a higher emission intensity in comparison to crops,” he said.
By 2050, Pradhan and co-author Jürgen Kropp projected that carbon emissions just from food waste could top over 2 billion metric tons a year. As high as that sounds, the true environmental cost is actually even higher. This measurement only counts carbon emissions; it doesn’t even begin to touch the amount of water, land, time, and sheer effort it takes to grow food that is ultimately thrown away.
The obvious solution is to reduce food waste itself, but that’s a complicated problem. Do you focus on the manufacturers and farmers to make things more efficient? Or maybe the grocery stores and restaurants that sell our food? Or perhaps you go even smaller, to the fridges and cupboards where our lettuce wilts and our cereals go stale.
The answer, of course, is that you do all of the above. Food waste is a distribution problem, a consumption problem, and a planning problem, and, to have any hope at stopping it, we’ll have to stop it at every point.