Healthy land provides the food, timber and fresh water essential to humanity’s survival, but a UN report says the climate crisis is damaging this precious resource with potentially irreversible consequences.

The abuse of land by razing forests, intensive farming and loss of soils also produces a quarter of global emissions, further worsening the climate emergency, says the report by the Intergovernmental Panel on Climate Change (IPCC).

It says ending the degradation of land can play an important role in securing a liveable planet by cutting emissions, providing sustainable food and reducing poverty.

Q&A What is the IPCC? Show Hide The Intergovernmental Panel on Climate Change (IPCC) is a body of the United Nations. Based in Geneva, it was established in 1988 by the World Meteorological Organization and the United Nations Environment Programme to determine the state of knowledge on climate change. For each report, the IPCC assembles hundreds of senior scientists from across the world to assess the current state of knowledge. It publishes major 'assessment' reports every 5–7 years, with the next, 'AR6' due in 2022, as well as producing ad hoc special reports. The IPCC has more than 190 member countries, and its reports are drafted and reviewed in several stages to guarantee their quality, with member governments signing off the final versions. The "Principles Governing IPCC Work" states it will assess: the risk of human-induced climate change

potential impacts

possible options for prevention In October 2018 it published a special report analysing current climate research stating that we have 12 years to limit climate change catastrophe, and that urgent changes are needed to cut risk of extreme heat, drought, floods and poverty.

“What the IPCC highlights is that we urgently need a revolution in the way we currently utilise land,” said Anna Krzywoszynska, of the University of Sheffield. “Food systems today are built not on soil but on the oil needed for chemicals and machinery.”

Clare Oxborrow, of Friends of the Earth, said: “The way land is being used and abused is rebounding on us. The scientific evidence is clear: political leaders must transform the way land and resources are used, otherwise life on Earth just won’t be possible.”

Land is heating up faster than the oceans: the average surface temperature is now 1.5C higher than in the late 19th century. This is already affecting food security, the IPPC report says, as heat, drought and changes in rainfall damage crops.

Play Video 7:53 It's time we stopped treating soil like dirt – video

Prof Pete Smith, of the University of Aberdeen, who was one of the report’s authors, said the food system would not be able to feed the world if global heating surged beyond 2C.

“Going into a world where we are way above 2C has massive implications for the food system and production in particular,” he said. “We get more droughts, more people going without food and who need more disaster relief. It’s a place we don’t want to go.”

Facebook Twitter Pinterest A solitary maize plant grows in a parched landscape in Hoopstad, South Africa, in 2016 during the worst drought in over a century. Photograph: Siphiwe Sibeko/Reuters

The burning of fossil fuels is the biggest source of carbon emissions and is still rising, despite the need for urgent cuts. But land use causes a quarter of greenhouse gas emissions, half from forest destruction and half from farming, including methane from cattle and rice paddies and nitrous oxide from chemical fertiliser use and manure.

The exploitation of land and fresh water today is unprecedented in human history, the IPCC report says. Three-quarters of all ice-free land is used by humans. Rising global population and consumption is driving the loss of 10bn trees a year and meat consumption has doubled since 1961. Intensive farming means soil is being lost 100 times as fast as it is being formed in ploughed fields.

However, the IPCC report says solutions exist. Among the most important is halting the destruction of forest, peatlands and wetlands, which store huge amounts of carbon and can absorb more if left undisturbed.

“Conserving what we have got is the first thing to do,” Smith said. “It is also a quick win that delivers across a whole range of things we want to do to preserve a liveable planet,” including halting the annihilation of wildlife, which some scientists think is the start of a new mass extinction.

Enabling the restoration of forests is also important, as is using farming techniques that preserve rather than erode soils. Cutting the amount of meat and dairy products eaten in rich nations is a “major opportunity”, the IPPC report says, due to the heavy environmental impact of intensively reared cattle. Drastically reducing food waste – 25-30% of all food is never eaten – is a priority as well.

Another opportunity is to help smallholder farmers around the world sustainably increase their yields, including by breeding new crop varieties that better withstand heat and drought.

Bioenergy crops have been suggested as a way to pull carbon dioxide from the atmosphere but the IPCC report warns that large-scale use could conflict with growing food, with serious consequences for food security.

Facebook Twitter Pinterest A man helps his children as they take part in a tree-planting campaign in New Delhi in 2018. Photograph: Chandan Khanna/AFP/Getty Images

The report says global heating could boost some crops in higher and cooler latitudes as growing seasons get longer and higher levels of CO2 in the air fertilises plants. “But in terms of global food production and food access it is definitely a net negative,” said Smith, as the most vulnerable populations live at lower latitudes such as in sub-Saharan Africa and India, where fierce temperatures will harm crops.

The special role of indigenous people is highlighted in the report. “Finally, the world’s top scientists recognise what we have always known,” said a statement by indigenous and community leaders from 42 countries that account for 76% of the world’s tropical forests. “We play a critical role in safeguarding the world’s lands and forests. The report recognises that strengthening our rights is a critical solution to the climate crisis.” Women must also have stronger rights, the report says, as they often do much of the farming but little of the decision-making.

Reyes Tirado, of the Greenpeace Laboratory at the University of Exeter, said: “This is a crisis of our own making but it’s a crisis we can solve if we act now. Changing the way we produce food and what we eat will protect our climate and promote food security.” She said freeing up land used for animal grazing and feed could allow forests to regrow.

Katherine Kramer, of Christian Aid, said: “The land sector alone cannot be a silver bullet. The need to end the fossil era as soon as possible remains as clear as ever. [But] we need land to be part of the solution as well.”