Agriculture Can Change World's Future

VANCOUVER - May 4/07 - SNS -- The fourth assessment report of the Intergovernmental Panel on Climate Change (IPCC) says agriculture can immediately start playing a major role in reducing greenhouse gas (GHG) emissions and helping reduce the volume of greenhouse gases in the atmosphere.

"Improved crop and grazing land management to increase soil carbon storage" would help clean up the atmosphere, the IPCC report said.

Agriculture can also work on "restoration of cultivated peaty soils and degraded lands; improved rice cultivation techniques and livestock and manure management to reduce CH4 emissions; improved nitrogen fertilizer application techniques to reduce N2O emissions; dedicated energy crops to replace fossil fuel use; (and) improved energy efficiency."

"Agricultural practices collectively can make a significant contribution at low cost to increasing soil carbon sinks, to GHG emission reductions, and by contributing biomass feedstocks for energy use (medium agreement, medium evidence)," the IPCC report said.

"A large proportion of the mitigation potential of agriculture (excluding bioenergy) arises from soil carbon sequestration, which has strong synergies with sustainable agriculture and generally reduces vulnerability to climate change," the IPCC report said.

"Stored soil carbon may be vulnerable to loss through both land management change and climate change. Considerable mitigation potential is also available from reductions in methane and nitrous oxide emissions in some agricultural systems. There is no universally applicable list of mitigation practices; practices need to be evaluated for individual agricultural systems and settings.

"Biomass from agricultural residues and dedicated energy crops can be an important bioenergy feedstock, but its contribution to mitigation depends on demand for bioenergy from transport and energy supply, on water availability, and on requirements of land for food and fibre production. Widespread use of agricultural land for biomass production for energy may compete with other land uses and can have positive and negative environmental impacts and implications for food security."

From a policy perspective, the IPCC report said government's need to provide: "Financial incentives and regulations for improved land management, maintaining soil carbon content, efficient use of fertilizers and irrigation."

And, policies "may encourage synergy with sustainable development and with reducing vulnerability to climate change, thereby overcoming barriers to implementation."

Between 1970 and 2004, global emissions of CO2, CH4, N2O, HFCs, PFCs and SF6, weighted by their global warming potential (GWP), have increased by 70% (24% between 1990 and 2004), from 28.7 to 49 Gigatonnes of carbon dioxide equivalents (GtCO2-eq). The emissions of these gases have increased at different rates. CO2 emissions have grown between 1970 and 2004 by about 80% (28% between 1990 and 2004) and represented 77% of total anthropogenic GHG emissions in 2004.

The largest growth in global GHG emissions between 1970 and 2004 has come from the energy supply sector (an increase of 145%). The growth in direct emissions in this period from transport was 120%, industry 65% and land use, land use change, and forestry (LULUCF) 40%. Between 1970 and 1990 direct emissions from agriculture grew by 27% and from buildings by 26%, and the latter remained at approximately at 1990 levels thereafter. However, the buildings sector has a high level of electricity use and hence the total of direct and indirect emissions in this sector is much higher (75%) than direct emissions.

The effect on global emissions of the decrease in global energy intensity (-33%) during 1970 to 2004 has been smaller than the combined effect of global income growth (77%) and global population growth (69%); both drivers of increasing energy-related CO2 emissions. The long-term trend of a declining carbon intensity of energy supply reversed after 2000. Differences in terms of per capita income, per capita emissions, and energy intensity among countries remain significant. Developed countries held a 20% share in world population, produced 57% of world Gross Domestic Product based on Purchasing Power Parity (GDPppp), and accounted for 46% of global GHG emissions.

The IPCC report said progress is being made. "A range of policies, including those on climate change, energy security, and sustainable development, have been effective in reducing GHG emissions in different sectors and many countries. The scale of such measures, however, has not yet been large enough to counteract the global growth in emissions.

"With current climate change mitigation policies and related sustainable development practices, global GHG emissions will continue to grow over the next few decades.

"The SRES (non-mitigation) scenarios project an increase of baseline global GHG emissions by a range of 9.7 GtCO2-eq to 36.7 GtCO2-eq (25-90%) between 2000 and 2030. In these scenarios, fossil fuels are projected to maintain their dominant position in the global energy mix to 2030 and beyond. Hence CO2 emissions between 2000 and 2030 from energy use are projected to grow 45 to 110% over that period.

"Two thirds to three quarters of this increase in energy CO2 emissions is projected to come from (developing nations), with their average per capita energy CO2 emissions being projected to remain substantially lower (2.8-5.1 MT CO2 per capita) than those in (developed nations) by 2030."