1. Climate Change Mitigation in Agriculture and Forestry (IPCC
WGIII AR5 Chapter 11) Cassia Moraes MPA in Development Practice at
Columbia University
2. Introduction - Agriculture, Forestry, and Other Land Use
(AFOLU) plays a central role for food security and sustainable
development. - Plants take up CO2 from the atmosphere and N from
the soil, redistributing it among different pools. CO2 and other
GHG - largely methane (CH4) and nitrous oxide (N2O) - are in turn
released to the atmosphere by plant respiration, by decomposition,
and by combustion. - AFOLU activities lead to both sources of CO2
and other GHG emissions, and sinks of CO2.
3. TOP 3 GHG Emissions from Agriculture 1) Enteric
Fermentation: Global emissions grew from 1.4 to 2.1 GtCO2eq/yr
between 1961 and 2010 annual grow of 0.70% (75% of the total
emissions coming from developing countries). 2) Manure: Global
emissions from manure (organic fertilizer manure deposited on
pasture) grew between 1961 and 2010 from 0.57 to 0.99 GtCO2eq/yr -
annual grow of 1.1%. 3) Synthetic Fertilizer: Emissions from
synthetic fertilizers grew from 0.07 to 0.68 GtCO2eq/yr at an
average rate of 3.9%/yr from 1961 to 2010.
4. GHG fluxes from forestry and other land use - AFOLU
accounted for about a third of anthropogenic CO2 emissions from
1750 to 2011 and 12% of emissions in 2000 to 2009. - Model results
indicate AFOLU emissions peaked in the 1980s in Asia and LAM
regions and declined thereafter. This is consistent with a reduced
rate of deforestation, most notably in Brazil, and some areas of
afforestation. - Burning vegetation releases CO2, CH4, N2O,
ozoneprecursors and aerosols to the atmosphere. When vegetation
regrows after a fire, it takes up CO2 and nitrogen.
5. Current Scenario - AFOLU is responsible for about a quarter
of anthropogenic GHG emissions (deforestation, livestocks
emissions, soil and nutrient management). - Unique scenario for
mitigation options: Increase removals of GHG (forestry); Reduction
of emissions (livestock and land use). - Critical factors that
impact this sector: population (growth), economic and technological
developments, changes in behaviour over time, and how these
translate into demand for food, fuel and other products.
6. - Mitigation include supplyside and demandside options: 1)
Supply-side: increasing production without increasing emissions
(e.g. sustainable intensification). (i) reducing emissions from
landuse change, land and livestock management; (ii) reducing
deforestation; (iii) increasing terrestrial carbon stocks
(sequestration in soils and biomass). (iv) reductions of direct
(e.g., agricultural machinery, pumps, fishing craft) or indirect
(e.g., production of fertilizers) energy-related emissions.
7. 2) Demand-side: agricultural CH4 and N2O would triple by
2055 to 15.3 GtCO2eq/yr if current dietary trends and population
growth were to continue. The potential to reduce GHG emissions
through changes in consumption was found to be higher than that of
technical mitigation measures. (i) reducing losses and wastes of
food in the supply chain and during consumption (3040% of all food
produced is lost); (ii) changing diets towards less GHGintensive
food (animal products vs plantbased options) ; (iii) reduction of
overconsumption in regions where this is prevalent.
8. - Landuse change can affect GHG balances, albedo and other
climate drivers (uncertain outcomes). - Bioenergy could play a
critical role for climate change mitigation, if deforestation is
avoided and bestpractice land management is implemented. - Any
largescale change in land use (e.g. bioenergy and carbon
sequestration) will likely increase the competition for land,
water, and other resources, and conflicts may arise. - Policies in
agriculture and forest management need to account for both
mitigation and adaptation.
9. The following changes were evaluated: no ruminant meat, no
meat, and a diet without any animal products. Changed diets
resulted in GHG emission savings of 3464% compared to the
businessasusual scenario; a switch to a healthy diet recommended by
the Harvard Medical School would save 4.3 GtCO2eq/yr (36%).
Adoption of the healthy diet (which includes a meat, fish and egg
consumption of 90 g/cap/day) would reduce global GHG abatement
costs to reach a 450 ppm CO2eq concentration target by ~50%
compared to the reference case (Stehfest et al., 2009). The
analysis assumed nutritionally sufficient diets; Reduced supply of
animal protein was compensated by plant products (soy, pulses,
etc.). (IPCC WGIII AR5 Chapter 11 p.38)
10. Resources: - IPCC Working Group III AR5 Chapter 11 -
Agriculture, Forestry and Other Land Use (AFOLU):
http://report.mitigation2014.org/drafts/final-draft-
postplenary/ipcc_wg3_ar5_final-
draft_postplenary_chapter11.pdf