Farmers urgently need help to adapt their methods of growing food if the world is to curb greenhouse gas emissions and prevent climate change pushing millions into hunger and poverty, the UN Food and Agriculture Organisation (FAO) said yesterday.

Small farmers who produce the bulk of food in developing countries are some of the most vulnerable to changes in climate and need help adapting to a warming planet, FAO said in a report.

Climate is expected to hit crop yields and livestock production and make the price of food more volatile, putting poor families at greater risk of hunger, the UN agency said.

“Unless action is taken now to make agriculture more sustainable, productive and resilient, climate change impacts will seriously compromise food production in countries and regions that are already highly food-insecure,” FAO director-general Jose Graziano da Silva said in the report.

“Hunger, poverty and climate change need to be tackled together. This is, not least, a moral imperative as those who are now suffering most have contributed least to the changing climate,” Graziano da Silva said.

The UN agency estimates that, with climate change, an additional 42 million people will be vulnerable to hunger in 2050. This figure does not include the growing numbers affected by extreme weather events.

The number of weather and climate-related disasters more than doubled in the past two decades compared with the preceding two, the UN Office for Disaster Risk Reduction said last week.

“Climate change is already happening, there is an increasing frequency and severity of extreme weather events,” said Kostas Stamoulis, head of FAO’s Social and Economic Development Department.

These climate shifts are reinforced by the recurring El Niño weather pattern, which takes place when water in the Pacific Ocean becomes abnormally warm, altering global weather patterns.

Hunger, poverty and climate change need to be tackled together. This is, not least, a moral imperative as those who are now suffering most have contributed least to the changing climate

More than 60 million people – two-thirds of them in east and southern Africa – faced food shortages this year because of droughts linked to El Niño.

“We all know that El Niño will happen but the intensity by which it happens is really scary,” Stamoulis said.

Smallholder farmers in Africa and Asia are already affected by rising temperatures, changes in rain patterns, frequency of droughts and rising sea levels.

“Larger farmers have the means to cope with those temporary threats, whereas small farmers can be totally wiped out because they don’t have the savings... or assets,” Stamoulis said.

Climate change is also expected to affect the nutrient content of food. The higher the concentration of CO2 in the atmosphere, the lower the nutritional content of crops like wheat, Stamoulis said.

“So not only people’s ability to acquire food will be reduced, but also the nutrient contents of whatever people will buy will be lower,” he said.

Agriculture, forestry and changes in land use together produce 21 per cent of global greenhouse gas emissions, making them the second largest emitter after the energy sector.

The raising of livestock alone produces nearly two-thirds of agriculture emissions, FAO said yesterday.

The figures do not include emissions produced from farm machinery, or in the transport, processing and storage of food.

“Those emissions come from the way we plough our soil, fertilise our crops, the way we use chemicals and manure, the way we raise our livestock, and the way we ... deforest,” said Stamoulis.

“If we don’t change the way we do business... every target ... to stabilise the climate will be missed,” he added.

A global agreement to tackle climate change, reached in Paris last year, will take effect on November 4. Work is due to start at UN climate talks in Morocco next month to hammer out the rules for putting the accord into practice.

The need for more sustainable agricultural practices will be an important part of that discussion, Stamoulis said.

These include growing crops which use less nitrogen and are more tolerant to drought, restoring forests, changing livestock feed and ploughing the land less.

Soil stores carbon, so the more it is ploughed and the deeper, the more carbon is released into the atmosphere.

How the food we eat makes the situation worse

■ Agriculture, forestry and changes in land use combined are the second largest source of greenhouse gases, producing 21 per cent of global emissions. The top emitter is the energy sector at 47 per cent.

■ To feed a growing global population, agricultural production must rise by about 60 per cent by 2050.

■ Climate change is expected to cut harvests in developing countries in the long term – although it may also improve some crop yields in the short term.

■ If climate change continues unchecked, it will make an additional 42 million people vulnerable to hunger in 2050, according to FAO calculations. However, that figure does not include people affected by extreme weather events such as drought or floods.

■ Small farmers, cattle herders and fishermen are the most vulnerable to climate change, and will need better access to technologies, markets, information and credit to adapt to climate change.

■ Agriculture suffered some 25 per cent of the total economic losses caused by climate-related disasters in developing countries between 2003 and 2013. For drought-related disasters, the share rose to 84 per cent.

■ Livestock alone produces nearly two-thirds of agricultural emissions – mainly from animal burping, manure and feed production. Synthetic fertilisers are the next major contributor, producing 12 per cent, and rice cultivation 10 per cent.

■ Carbon dioxide emissions from agriculture are mainly caused by changes in land use, such as converting forests to pasture or cropland, and land degradation from over-grazing.

■ Most direct emissions of methane and nitrous oxide are caused by livestock flatulence, rice production in flooded fields and the use of nitrogen fertilisers and manure.a

■ Nearly 50 per cent of world food production depends on nitrogen fertiliser. The other half depends on nitrogen found in soil, animal manure, nitrogen-fixing plants, crop residues, wastes and compost.

■ More than a third of food produced worldwide is lost or wasted. Rotting food produces methane, which is a greenhouse gas 25 times more potent than carbon dioxide.

■ Deforestation and forest degradation account for about 11 per cent of all greenhouse gas emissions, more than the world’s entire transport sector.

■ Reducing agriculture emissions depends partly on cutting food waste and loss, as well as shifting people’s diets – including consuming less animal products – and changing farming practices.