The latest report from the UN Intergovernmental Panel on Climate Change (IPCC) was broadly welcomed by scientists across the globe as a framework to transform land use and increase food security.
Although the report stopped short of explicitly advocating going meat-free, it calls for big changes to farming and eating habits to limit the impact of population growth and changing consumption patterns on already over-exploited land and water resources.
"This is a perfect storm," said Prof Dave Reay of the University of Edinburgh, who was an expert reviewer for the report. "Limited land, an expanding human population, and all wrapped in a suffocating blanket of climate emergency. Earth has never felt smaller, its natural ecosystems never under such direct threat."
Dr Oyinlola Oyebode, associate professor in public health at the University of Warwick, said the IPCC verdict fits with growing evidence of the multiple benefits that could accrue if people shift their diet towards plant-based alternatives to meat.
These benefits included reducing greenhouse gas emissions, and releasing land which could then be reclaimed as habitat for animal and plant species.
“In addition, though, there are benefits to human health.”
Jonathan Baillie, chief scientist for the National Geographic Society, said the IPCC report was another important wake-up call to find a more sustainable path.
“This is a global problem, which requires action by all sectors of society – countries, companies and communities – to solve.”
Oxfam's senior climate policy advisor Aditi Sen said land management was central to the fight against the climate crisis and hunger. Industrial agriculture, deforestation and increasing weather shocks were destroying the land needed for food, while the world's poorest were hit hardest.
Almost three-quarters of ice-free land was now directly affected by human activity, the report says
“Politicians must aim for zero hunger as well as zero emissions. They must reject false solutions that divert land away from growing food and into producing crops and trees for energy and carbon capture.”
IPCC representative Prof Jim Skea of Imperial College London said land was already struggling and climate change was adding to its burden. Almost three-quarters of ice-free land was now directly affected by human activity, the report says.
“There are certain kinds of diets that have a lower carbon footprint and put less pressure on land,” he said.
Large-scale tree-planting and bioenergy production are important tools to limit global warming, but could threaten food security, according to the IPCC. In late-running negotiations on how to summarise the latest science for policymakers, representatives of forest nations stressed that with sustainable management, these conflicts could be minimised.
“Land already in use could feed the world in a changing climate and provide biomass for renewable energy, but early, far-reaching action across several areas is required,” said Hans-Otto Pörtner, one of the other scientists coordinating the report. “Also for the conservation and restoration of ecosystems and biodiversity.”