Look after land to tackle climate change, experts urge

The world must “look after the land” to help tackle climate change, experts warn as rising temperatures put food supplies at risk.

Global warming will increasingly lead to extremes such as drought, heatwaves and wildfires and threaten food security, reducing yields, pushing up food prices and disrupting supply chains, a new UN report said.

But sustainable farming, changing diets to eat less meat, replanting forests and protecting habitats such as peatland and mangroves can cut climate emissions and deliver other benefits such as securing food supplies.

Land is already under pressure, with around 70% of the world’s ice-free land affected by human activity – and climate change is driving more problems such as turning land to desert, and soil and coastal erosion, the study said.

How people use the land is also contributing to global warming – with activities such as growing crops, raising livestock and cutting down forests accounting for almost a quarter of greenhouse gases (23%) between 2006 and 2017.

The latest report from the Intergovernmental Panel on Climate Change (IPCC) comes after a study from the international body last year called for “unprecedented” action to slash carbon emissions to zero by 2050 and limit dangerous global warming.

Experts behind the new report called for swift action to protect land to curb emissions, help nature and ensure food security.

Dr Jo House, from the University of Bristol, said: “We have to look after the land, the land is doing many things for us and we need to support the land for it to continue to do that.”

Professor Jim Skea, from Imperial College London, said: “The human race has been rather abusing it and we need to look after it for our own benefit as well.

“Land is already struggling under pressures we put on it at the moment. The issue is climate change is adding to all the other burdens we put on the land system.”

And he said: “There’s a lot of actions that can be taken for the land sector to help with climate change, there are many ways of managing it to reduce the impacts of land and bring benefits like building up soil carbon.”

He added: “In the past we’ve often thought dealing with climate change is about renewable energy and energy efficiency, but this is bringing land much more into the foreground.”

The report said balanced diets with plant-based foods such as grains, beans and lentils, nuts, fruits and vegetables and animal-based food produced in sustainable systems with low greenhouse gas emissions can help curb climate change and benefit health.

Dr House said it was not up to scientists to tell people what to do.

But she said red meat had a much higher carbon impact than other types of meat due to the emissions given off during production as well as clearing land to grow animal feed.

The report said around 13% of carbon dioxide between 2007 and 2016 was caused by human uses of land, mostly from cutting down forests.

Land also accounted for 44% of methane emissions, with livestock such as cattle and expansion of rice paddies driving rising levels of the gas, and 82% of nitrous oxide emissions, coming from fertilisers for crops and from livestock.

At the same time, around 25-30% of all food produced is lost or wasted, contributing more greenhouse gases, the report by experts from around the world found.

Sustainable food production, improved forest management, protecting soils, conserving habitats and restoring land, reducing deforestation and food loss and waste can all tackle climate change, help wildlife and boost livelihoods.

Conserving peatlands, wetlands, grasslands, mangroves and forests can have an immediate impact.

Other measures could include replanting forests and using more trees as part of farms in “agroforestry”, for example for shading livestock or as crops such as apples which could be planted through the middle of fields of other crops.

But the experts warned that planting monocultures of trees or crops for bioenergy on a large scale in an unsustainable way will have negative impacts, and sufficient land must be available to grow food.

They also warn that tackling emissions from land is not on its own enough to curb climate change, and greenhouse gases must be slashed from all sectors to keep global warming to well below 2C or 1.5C above pre-industrial levels.