Food could lead planet to warm 1°C by 2100 – 03/06/2023 – Environment

If current trends continue, global food consumption could eventually lead to an increase of about 1°C in Earth’s average temperature by the end of the century. This is what an analysis by US scientists indicates, which sought to make a detailed inventory of the emissions of gases that cause the climate crisis from agriculture and animal husbandry around the world.

The relative good news of the work, which has just been published in the scientific journal Nature Climate Change, is that this effect on the climate is not something inevitable. According to the researchers’ calculations, more than half of this warming may not happen —as long as measures such as better agricultural practices, less waste and a reduction in red meat consumption are adopted.

The work, coordinated by Catherine Ivanovich, from the Department of Earth and Environmental Sciences at Columbia University, adopted a series of methodological precautions to more precisely measure the effect of greenhouse gases (basically, those that retain heat close to the surface of the Earth) derived from food consumption.

It is common for people to talk only about carbon dioxide or carbon dioxide (CO_two) as the main greenhouse gas, taking into account its production during the burning of fossil fuels (gasoline or diesel, for example). However, in the case of gas emissions from agriculture and livestock, equally relevant is methane (CH₄).

Large amounts of methane are produced, for example, during the fermentation of plant matter in the digestive system of animals such as cattle, and also in flooded areas where rice is planted. Methane is capable of retaining about one hundred times more heat than carbon dioxide. On the other hand, it lasts much less in the atmosphere (about a decade, against hundreds of years of carbon dioxide).

On the one hand, Ivanovich and his colleagues weighed the contributions of different gases and their temporal effect on the atmosphere. On the other hand, they took into account studies on emissions linked to almost a hundred food products and their consumption in 171 countries, based on data from the FAO (Food and Agriculture Organization of the United Nations).

The next step was to use this snapshot of the sector’s current emissions to estimate how they might evolve in the future and how they would affect the global climate, using computer models already established for this purpose.

Depending on human population growth through 2100, the team estimated that the temperature rise from food consumption could be between 0.7°C and 0.9°C (with a margin of error of 0.2°C plus or minus). any less).

Of this total, almost 60% are associated with the consumption of meat, milk and derivatives, while 19% are linked to the consumption of rice. Therefore, these are the priority areas for interventions, according to the research team.

In the case of rice cultivation, the team calculates that it would be possible to cut greenhouse gas emissions in half using planting methods that minimize water use (the context in which methane emissions occur) without negative effects on productivity.

The situation is more complex in the case of red meat, as it requires changing eating habits, which have a strong cultural component.

The researchers used a recommendation made by the Harvard Medical School, which suggests eating red meat only once a week, allowing for daily consumption of poultry, eggs or fish. Following this approach, it would be possible to reduce the predicted warming by the end of the century by 0.2°C.

Other relevant measures would be approaches to decarbonize food production and transport (through renewable energies in irrigation, harvesting, transport, etc.) and waste reduction, point out the researchers.

_{The Planeta em Transe project is supported by the Open Society Foundations.}