Emissions from agriculture, forestry and fisheries have nearly doubled over the past 50 years and could increase an additional 30 per cent by 2050, without greater efforts to reduce them, new FAO estimates of greenhouse gas data shows
This is reportedly the first time that FAO has released its own global estimates of greenhouse gas (GHG) emissions from agriculture, forestry and other land use (AFOLU), contributing to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC).
Agricultural emissions from crop and livestock production grew from 4.7bn tonnes of carbon dioxide (CO2) equivalents in 2001 to over 5.3bn tonnes in 2011, a 14 per cent increase. The increase occurred mainly in developing countries, due to an expansion of total agricultural outputs.
Meanwhile, the net GHG emissions due to land use change and deforestation registered a nearly 10 per cent decrease over the 2001-2010 period, averaging around three billion tonnes CO2 eq per year over the decade. This was the result of reduced levels of deforestation and increases in the amount of atmospheric carbon being sequestered in many countries.
FAO’s data based on a country reports show that while those emissions continue to increase, they are not growing as fast as emissions from fossil fuel use in other sectors, so the share of AFOLU out of total anthropogenic emissions is actually decreasing over time.
The largest source of GHG emissions within agriculture is enteric fermentation - when methane is produced by livestock during digestion and released via belches - this accounted in 2011 for 39 per cent of the sector’s total GHG outputs. Emissions from enteric fermentation increased 11 per cent between 2001 and 2011.
Emissions generated during the application of synthetic fertilizers accounted for 13 per cent of agricultural emissions (725 metric tonnes CO2 equivalent) in 2011, and are the fastest growing emissions source in agriculture, having increased some 37 per cent since 2001.
Greenhouse gases resulting from biological processes in rice paddies that generate methane make up 10 per cent of total agricultural emissions, while the burning of savannahs accounts for five per cent.
In 2011, 44 per cent of agriculture-related GHG outputs occurred in Asia, followed by the Americas (25 per cent), Africa (15 per cent), Europe (12 per cent), and Oceania (four per cent), according to FAO’s data. In 1990 however, Asia’s contribution to the global total (38 per cent) was smaller than at present, while Europe’s was much larger (21 per cent).
“FAO’s new data represent the most comprehensive source of information on agriculture's contribution to global warming made to date,” said Francesco Tubiello of the Organization’s Climate, Energy and Tenure Division. “Up to now, information gaps have made it extremely difficult for scientists and policymakers to make strategic decisions regarding how to respond to climate change and has hampered efforts to mitigate agriculture's emissions.”
“Data on emissions for AFOLU activities support member countries in better identifying their mitigation options and enable their farmers to take faster and more targeted climate-smart responses. This in turn improves their overall resilience and their food security. It also allows the countries to tap into international climate funding and accomplish their rural development goals. We also see much interest in capacity development on these topics at country level and respond to these needs through regional and country-level activities around the globe,” he added.