United Nations — A new United Nations report has described farming, land degradation and desertification as critical frontlines in the battle to keep the global rise in temperatures below the benchmark figure of 2 degrees Celsius.
The 43-page study from the U.N.'s Intergovernmental Panel on Climate Change (IPCC) released this week says better management of land can help combat global warming and limit the release of greenhouse gases.
"Climate change poses a major risk to the world's food supply, and while better land management can help to combat global warming, reducing greenhouse gas emissions from all sectors is essential," U.N. spokesman Stefan Dujarric told reporters Thursday.
The report offered "compelling evidence" for redoubling global efforts and shows that while "food security is already at risk from climate change, there are many nature-based solutions that can be taken," added Dujarric.
Among the IPCC's recommendations were calls for vigorous action to halt soil damage and desertification and for people globally to throw less food into trash cans, whether in private homes or out the back of supermarkets and factories.
Instead, scrap food can be used to feed farm animals, in some cases. Alternatively, food waste can be donated to charities so that homeless people and others in need get much-needed meals.
Controversially, the IPCC also noted that more people could be fed using less land if individuals cut down on eating meat and switched up their diets by consuming more "plant-based foods".
"Some dietary choices require more land and water, and cause more emissions of heat-trapping gases than others," said Debra Roberts, co-chair of an IPCC working group.
"Balanced diets featuring plant-based foods, such as coarse grains, legumes, fruits and vegetables, and animal-sourced food produced sustainably in low greenhouse gas emission systems, present major opportunities for adaptation to and limiting climate change."
The report was co-authored by 107 scientists and was finalised this week at talks in Geneva, Switzerland.
It is called "Climate Change and Land, an IPCC special report on climate change, desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystems".
The report's findings would be key at the Conference of Parties of the U.N. Convention to Combat Desertification (UNCCD) in New Delhi, India, in September and at other confabs over the coming months, said Dujarric.
Some 500 million people live in areas facing desertification, IPCC scientists said. These regions are more vulnerable to climate change and such extreme weather events as droughts, heatwaves, and dust storms.
Once land is degraded, it becomes less productive and unsuitable for some crops. It also becomes less effective at absorbing carbon, which drives a vicious cycle of rising temperatures degrading soils even more.
"Land plays an important role in the climate system," Jim Skea, co-chair of an IPCC working group, said in a statement accompanying the document.
"Agriculture, forestry and other types of land use account for 23 percent of human greenhouse gas emissions. At the same time natural land processes absorb carbon dioxide equivalent to almost a third of carbon dioxide emissions from fossil fuels and industry."
Under the landmark 2015 Paris Agreement, governments pledged to limit the rise in average global temperatures to "well below" 2°C above pre-industrial times, and ideally to 1.5°C. The world has already heated up by about 1°C.
Droughts and heatwaves are getting worse, according to the UNCCD. By 2025, some 1.8 billion people will experience serious water shortages, and two thirds of the world will be "water-stressed".
Though droughts are complex and develop slowly, they cause more deaths than other types of disasters, the UNCCD warns. By 2045, droughts will have forced as many as 135 million people from their homes.
But there is hope. By managing water sources, forests, livestock and farming, soil erosion can be reduced and degraded land can be revived, a process that can also help tackle climate change.
"The choices we make about sustainable land management can help reduce and in some cases reverse these adverse impacts," said Kiyoto Tanabe, co-chair of an IPCC task force on greenhouse gasses.
"In a future with more intensive rainfall the risk of soil erosion on croplands increases, and sustainable land management is a way to protect communities from the detrimental impacts of this soil erosion and landslides."