Humans must change diets to save planet, says UN climate change report

Top UN scientists have warned humans to drastically change their diet to limit the effects of climate change.

Balanced diets could help create a sustainable future, a special report by the Intergovernmental Panel on Climate Change looking at the relationship between climate change and land use found. The report was leaked on Monday before being officially unveiled on Thursday.

"Some dietary choices require more land and water, and cause more emissions of heat-trapping gases than others," said Debra Roberts, one of the report's 107 authors.

“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.”

Around 2 billion adults are overweight or obese, but 821 million people are still undernourished, “highlighting the need to reform the global food system”, the report said.

Greenpeace Switzerland activists unveiled a banner outside the UN meeting in Geneva emblazoned with “Less Meat = Less Heat. Climate Action NOW!”

According to the IPCC, the meat consumption has more than doubled in the past 60 years as land was converted to agricultural use at what has been described as “an unprecedented rate in human history”.

The Intergovernmental Panel on Climate Change also urged changes to land management and food production in order to limit global warming to 2° C.

It said the use of bioenergy — biofuels such as wood or crop waste — needs to be carefully managed to avoid risks to food security.

The UN’s scientists also warned of water scarcity, soil erosion, vegetation loss, wildfire damage and a decline in tropical crops due to climate change.

The report says humans now use 72 per cent of the planet's ice-free surface to feed, clothe and support the growing population.

"Agriculture, forestry and other types of land use account for 23% of human greenhouse gas emissions," said Jim Skea, a co-chair of one of the IPCC's three working groups on the topic.

"New knowledge shows an increase in risks from dryland water scarcity, fire damage, permafrost degradation and food system instability, even for global warming of around 1.5°C,” said Valérie Masson-Delmotte, one of the IPCC working group co-chairs.

Higher carbon dioxide levels are expected to lower the “nutritional quality of crops,” the report said.

That could severely hike food prices. Cereal prices could increase by 7.6 per cent by 2050 due to climate change, the report estimated.

"Food security will be increasingly affected by future climate change through yield decline — especially in the tropics — increased prices, reduced nutrient quality, and supply chain disruptions,” said Priyadarshi Shukla, co-chair of one of the IPCC working groups.

“We will see different effects in different countries, but there will be more drastic impacts on low-income countries in Africa, Asia, Latin America and the Caribbean,” he said.

The IPCC has warned that a rise in temperature higher than 1.5°C above pre-industrial levels could trigger climate destabilisation.

The report’s 107 authors came from 52 countries, the majority from developing countries, and 40 per cent of them were women.

Scientists declared July the warmest month ever recorded globally on Monday on the back of Europe’s ‘Sahara plume’ heatwave, with record high temperatures recorded in the UK, Germany, Belgium and the Netherlands