Global food production and consumption habits must change to contain global warming, according to a United Nations report evaluating the effects of climate change on land.
Published on Thursday, the report by the Intergovernmental Panel on Climate Change (IPCC) - which met in Geneva this week - recommends embracing new farming methods and making major dietary changes such as cutting back on meat consumption. The document provides guidance to governments on ways to implement the 2015 Paris agreement and avoid runaway climate change ahead of a conference focused on the issue later this year in Chile.
Since pre-industrial times, land surface temperature has increased twice as much as the global average, by 1.53°C compared to 0.87°C. Sea level rise is also increasing the pressure on the land, notes the 60-page summary of the report for policymakers. The experts examined the links between land use, food security and climate change.
Any scenario to limit global warming to less than 2°C by 2100 "requires land-related mitigation and land-use change," concludes the report, which was approved on Wednesday by 195 countries, including Switzerland, after 28 hours of discussion. The IPCC recommends cutting back on meat in favour of plant-based diets.
In Switzerland, agricultural land occupies a major partexternal link of the surface area, 36%.
Ahead of the report's release, Greenpeace activists in Switzerland unveiled a banner outside the meeting reading "Less Meat = Less Heat. Climate Action Now.”
Such dietary adjustments could contribute, according to estimates, to the release of up to millions of square kilometres of land and, per year, to a mitigation of up to 8 gigatonnes of CO2 equivalents by 2050. More than 70% of the land area, according to specialists, is used in total to satisfy the needs of the population.
Since 1961, per capita production of vegetable oils and meat has more than doubled. Calories have increased by a third. While nearly 830 million people are undernourished, about 2 billion are overweight.
Human land use accounts for nearly a quarter of greenhouse gas emissions, including nearly half of the methane released. This activity is responsible for the degradation of 25% of the land surface. In particular, drylands increased by an average of 1% between 1961 and 2013.
Climate threats will depend on the size of the population and the degree of temperature increase. Those of increased fires or food instability are considered "high" with an additional 1.5°C and "very high" with 2 or 3°C more. Another problem is that a scenario of a population of 9 billion people by 2100 would increase the price of some commodities by more than 7% by 2050.
Depending on the region, changes in land conditions can "increase or decrease" the rate of global warming, the IPCC concludes. This warming will be accompanied by heavy rains and floods as well as heat and droughts causing food instability.