The food system alone could warm the climate by almost 1°C by 2100, but this scenario is not inevitable because a healthier diet and other measures could prevent much of it, according to a study published on Monday.
“A continuation of current dietary patterns around the world by the end of the century could add about 1°C of additional warming,” concludes a group of US-based researchers in a study published by the journal Nature climate change.
The authors propose a range of 0.7 to 0.9°C warming, with a margin of 0.2°C, depending on population growth scenarios. While the planet has already warmed by almost 1.2°C compared to the end of the 19e century, the food system leads on its own and in all cases to a warming higher than the most ambitious objective of the Paris agreement (1.5°C).
Most of this warming is caused by foods that are important sources of methane: meat from ruminants such as beef and mutton, which belch out this powerful greenhouse gas, as well as dairy products or rice.
The other sources come from CO2 and nitrous oxide (N2O), the latter being emitted in particular during the use of synthetic fertilizers.
The researchers reached these conclusions based on an inventory of 94 foods, with more precise modeling of the effect of these different greenhouse gases.
“These results show that the urgency to mitigate emissions from the food sector is essential to work towards a secure climate future,” said one of the study’s authors Catherine Ivanovich, from Columbia University.
However, the future is not written: more than 55% of this warming can be avoided by improving agricultural production practices, reducing waste and adopting a “healthy diet”, underline the authors.
For this last point, they based themselves on medical recommendations in favor of reducing meat consumption – especially red meat – in favor of other proteins containing less saturated fat and cholesterol.