Food causes third of all man-made greenhouse gases
Cuts needed, from fertilisers to transport
Food production accounts for up to 29 per cent of man-made greenhouse gases, twice the amount the UN has estimated comes from farming, according to a study published yesterday.
Looking at emissions across the food system, including forest clearance, fertiliser production and transport, rather than just farming itself, agriculture research organisation CGIAR said much more work was needed to cut climate change emissions from food.
Its report, Climate Change and Food Systems, estimated food production was responsible for between 19 and 29 per cent of mankind’s total greenhouse emissions, far above UN estimates of 14 per cent based on a narrower definition of farming.
“From a food point of view (the UN approach) doesn’t make sense,” said Bruce Campbell, who heads the CGIAR research programme on climate change, agriculture and food security.
Many countries could make big cost savings bycutting emissions, he said. “There are good economic reasons to improve efficiency in agriculture, not just to cut greenhouse gas emissions.”
Global changes in diet, shifting towards vegetarianism from meat, would also help. Growing crops to feed to cows, pigs or sheep takes up far more land and emits more greenhouse gases than producing crops for human consumption.
A separate report by the CGIAR climate programme indicated that climate change is likely to reduce yields of the three biggest crops judged by calorie production – maize, wheat and rice – in developing nations in coming decades.
That could force some farmers to make radical shifts to growing more heat-, flood- or drought-tolerant crops, according to the report, Recalibrating Food Production in the Developing World.
More resilient crops including yam, barley, cowpea, millet, lentils, cassava and bananas could fill in the gaps caused by declining harvests of more sensitive crops, it said.
“The world’s agricultural systems face an uphill struggle in feeding a projected nine to 10 billion people by 2050,” it said. The world population is now just above seven billion.