The research, led by Dr. Eric Davidson and published in Environmental Research Letters, examines the challenge of stabilizing nitrous oxide (N2O) emissions by 2050 – the most aggressive reduction scenario outlined in the IPCC draft report. Unlike the two most prevalent greenhouse gases, carbon dioxide (CO₂) and methane (CH₄), N2O is a critical element in food production. Its main sources are manure and synthetic fertilizers.
Davidson, president and a senior scientist at the Woods Hold Research Center in Massachusetts, said that stabilizing N2O emissions by 2050 would require improved management of fertilizer and manure sources, as well as reduction of the developed world’s per capita meat consumption to reduce fertilizer demand and reduce the growth in the amount of manure being produced.
“We have the technical know-how and the tools to greatly improve efficiencies of fertilizer use in agriculture, although several economic and political impediments often stand in the way of their adoption,” Davidson said.
He calculated that meat consumption would need to be reduced by half using Food and Agriculture Organization (FAO) data, which assume the world’s population will hit 8.9bn by 2050, with an increased daily per capita calorie intake of 3130 kcal. The FAO data also suggest that average meat consumption per person in the developed world will rise from 78kg per year in 2002 to 89kg per year in 2030. For the developing world, per capita consumption is predicted to increase from 28kg per year in 2002 to 37kg per year in 2030.
As for whether such a major reduction in meat consumption would be possible, Davidson said: “That will depend, not only on education about diet, but also on prices of meat. Some agricultural economists think that the price of meat is going to go way up, so that per capita consumption will go down, but those are highly uncertain projections.”