Climate change and poor management practices threaten the world's farmlands and food security, the United Nations said yesterday in a major report.
Deforestation and loss of peatlands, mangroves and grasslands for large-scale agriculture are degrading life-giving soils that humanity needs to feed and clothe itself, cutting yields, threatening food supplies for millions and raising the risk of mass migration.
Such large-scale damage to the environment is making the land more vulnerable to risks from more extreme weather which, in turn, is fuelling more severe temperature and rainfall changes locally in a vicious circle, the report by the Intergovernmental Panel on Climate Change (IPCC) concluded.
The far-reaching study by more than 100 authors from 52 countries was finalised on Wednesday in Geneva after nearly a week of negotiations between scientists and policymakers from 195 countries. The authors examined thousands of studies over about three years to better assess the links between climate change, food security, land degradation and desertification.
The report is a vital guide for governments as climate change risks grow in a world where the population is heading for 10 billion people by mid-century, threatening to place even greater strain on the planet's limited resources.
The IPCC last October looked at the steps needed to limit global warming to 1.5 deg C, a key goal of the Paris Climate Agreement. It concluded that deep emission cuts are needed before 2030 to achieve this.
While last year's report looked at the sources of emissions, this year's focus is on how human activity is eroding the planet's natural defences to climate change.
The report said the way the earth's land is used is a key part of the solution to reducing the risks from climate change.
Key findings of the report
Here are some of the key findings of the IPCC's special report on land use. The report points to an urgent need to reform the way food is grown.
• Humans directly use more than 70 per cent of the earth's ice-free land surface for food, feed, fibre, timber and energy. The land and ecosystems such as forests play a vital role in regulating the climate and watersheds essential for mankind. The land is both a source and a sink for greenhouse gas emissions, but booming demand for food means it is a major source of planet-warming emissions. Data since 1961 shows that rapid population growth and changing diets have caused unprecedented rates of land and water use. Rapid agricultural expansion has led to widespread destruction of forests, wetlands, grasslands and other ecosystems, and increased land degradation and desertification, leading to widespread soil erosion.
• About a quarter of the earth's ice-free land area is subject to human-induced degradation. This has made the land more vulnerable to further erosion and greater extremes of heat, drought and floods caused by climate change. This, in turn, will affect yields and food security for millions more people in the coming decades.
• Asia and Africa are projected to have the highest number of people vulnerable to increased desertification. The tropics and subtropics are projected to be most vulnerable to crop yield decline.
• About 821 million people, many in poorer dryland areas, are undernourished.
EMISSIONS, FOOD WASTE
• Agriculture, forestry and other land uses are responsible for about 23 per cent of mankind's greenhouse gas emissions during the 2007-2016 period. Data available since 1961 shows the per-capita supply of vegetable oils and meat has more than doubled, and the supply of food calories per capita has increased by about one-third. Currently, 25 per cent to 30 per cent of total food produced is lost or wasted.
• Steps including sustainable food production, improved forest management, ecosystem conservation and land restoration, reduced deforestation and cutting food waste can all help farmers and societies adapt and improve food security.
• Preserving and restoring wetlands, mangroves and peatlands can also lock away large amounts of carbon dioxide, the main greenhouse gas, and offer quick benefits.
The land, from tropical forests and peatlands to desert grasslands, soaks up large amounts of planet-warming carbon dioxide (CO2), the main greenhouse gas. It is part of a natural cycle in which carbon is produced and recycled by plants on land and organisms in the oceans as a way to regulate the climate.
But large-scale burning of fossil fuels such as oil, gas and coal, as well as the clearing and burning of forests, has disrupted the natural order, leading to ever greater amounts of CO2 that nature can no longer absorb, fuelling a warming world.
The IPCC said that reducing greenhouse gas emissions from all sectors, including land and food, was essential.
The report found that there are many ways to reduce the impact on farmlands, including switching to less intensive cropping practices, ecosystem conservation and land restoration, reducing deforestation, cutting food waste and switching to climate-friendly diets.
During a news conference yesterday, Dr Valerie Masson-Delmotte, one of the report's 107 authors, stressed the need for early action.
"It takes time for ecosystems, soils and trees to take up carbon, so early action gives more benefits. It also takes time for education, capacity building and training, so the practices are learnt and can be implemented," she said.
The report also highlights the changes in diets in recent decades, including surging demand for meat and vegetable oils. Producing both releases a lot of carbon.
It also highlighted food waste. At present, between 25 per cent and 30 per cent of total food produced is lost or wasted, the report said.
Food waste remains a big problem in Singapore, with about a fifth of all local and imported food lost every year, a recent study found.
The Singapore Food Agency (SFA) and National Environment Agency said they have strategies to reduce food waste, including waste minimisation guidebooks for supermarkets and other businesses.
An SFA spokesman said the agency is exploring Good Samaritan laws for Singapore to ease business concerns over the donation of excess food.
She added: "However, it is important to ensure that any food donated is fit for consumption. In considering the feasibility of such laws, there is a need to strike a balance between facilitating food donation and ensuring that food donors and food distributors exercise due care and practise good hygiene when distributing donated food."