![\"\"](\"https:\/\/images.newscientist.com\/wp-content\/uploads\/2024\/08\/12145543\/SEI_217164503.jpg\")
<\/div>Cattle farming produces large amounts of greenhouse gases<\/p>\n
Alan Hopps\/Getty Images<\/p>\n<\/div>\n<\/figcaption><\/figure>\n<\/p>\n
With the world\u2019s population growing, the only way to reduce the enormous greenhouse gas emissions from farming is to make food production ever more efficient. Unfortunately, efficiency gains have stalled since 2010, meaning farming emissions \u2013 and deforestation \u2013 could rise sharply as demand for food continues to grow.<\/p>\n
Lin Ma<\/a> at the Chinese Academy of Sciences in Shijiazhuang and his colleagues reached this conclusion by analysing existing data to estimate greenhouse gas emissions per unit of protein produced between 1961 and 2019. They chose protein rather than calories because it is a better measure of food quality, says Ma.<\/p>\n Between 1961 and around 2010, emissions per unit of protein fell by two-thirds, the team found. But since then, there have been no further improvements and there are even some signs of an increase. Farming is responsible for around a third of all greenhouse gas emissions<\/a> and demand for food is projected to rise by up to 50 per cent by 2050. If the climate efficiency of farming is no longer improving, this means that emissions from farming will rise by 50 per cent too, the researchers warn.<\/p>\n What\u2019s more, if the efficiency of farming<\/a> isn\u2019t improving, the only way to increase production is to clear more land for farms, they say, leading to yet more deforestation and loss of biodiversity.<\/p>\n <\/p>\n \u201cThat would be very bad news. We need to be greatly reducing emissions, not increasing them,\u201d says Richard Waite<\/a> at the World Resources Institute in Washington DC, who wasn\u2019t involved in the research.<\/p>\n \u201cThe ongoing \u2013 and even accelerating \u2013 expansion of cropland since the turn of the century is extremely concerning because pathways to stay within 1.5\u00b0C [of global warming] depend on ending deforestation as soon as possible,\u201d he says.<\/p>\n There are many reasons why climate emissions per unit of protein produced are no longer falling, says Dan Rejto<\/a> at the Breakthrough Institute, who wasn\u2019t part of the team. One is that people around the world are eating more meat, which is much more greenhouse gas-intensive than plant-based foods<\/a>. The fact that large quantities of crops are now turned into fuel rather than food<\/a> could be another of these drivers, he says. \u201cThe rise of crop-based biofuels likely explains some of the slowdown in decarbonisation that the paper finds.\u201d That is because biofuel crops, grown for energy, are chosen for being calorie-heavy rather than protein-rich, reducing their efficiency as measured by Ma\u2019s team.<\/p>\n Another potential driver is the increase in extreme weather, which is affecting yields and food prices around the world<\/a>. The study didn\u2019t look at this, says Ma. \u201cBut I believe the impacts of the extreme weather on crop yields were relatively small before 2019.\u201d\u00a0 Topics:<\/p>\n<\/section><\/div>\n
<\/b><\/p>\n
<\/strong><\/p>\n