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