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Short Background on Climate Change and Greenhouse Gases Dr Ruth Nussbaum ProForest Presentation to the RSPO GHG WG2 meeting in Feb 2010
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The Greenhouse Effect Source: GLECOSYS Solar radiation enters the atmosphere The earth’s surface is warmed and radiates heat back into the atmosphere Some energy is radiated into space, the rest is trapped as heat in the atmosphere – GHGs increase the amount of energy trapped
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Main Greenhouse Gases Carbon dioxide (CO 2 ) Stays in atmosphere: 1-2 yrs (uncertain) Global warming potential: 1 (all other gases GWP relative to CO 2 ) Methane (CH 4 ) Stays in atmosphere: 12±3 yrs Global warming potential: 23 (IPCC) 1 tonne CH 4 = 23 t CO2e Nitrous Oxide (N 2 O) Stays in atmosphere: 114 yrs Global warming potential: 296 (IPCC) 1 tonne N 2 O = 296 t CO2e
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Converting C to CO2e Carbon converted to CO2-equivalent (CO2e) using molar weights –Carbon (C)= 12 –CO2 = 12+16+16 = 44 –Conversion factor (CF) = 44/12 = 3.67 –CO2e = tonnes of C * CF Biomass conversion to CO2e –Trees approximately 50% C –CO2e = tonnes of biomass * 0.5 * 3.67
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Source: IPCC 2007 GHG Concentrations Radiative Forcing (W/m2) Atmospheric Concentration
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Annual Global Sources and Sinks of GHGs Sources Fossil Fuels Deforestation 6.4 Gt1.6 Gt Figures taken from Global Carbon Project and are indicative only Gt = giga tonne = 1 billion tonnes += Sinks Atmosphere 3.1 Gt Uncertain where this CO 2 is going: assumed to be a land sink (e.g. regenerating forest) Oceans 2.2 Gt + 2.6 Gt + These values are in addition to background naturally occurring sources and sinks For 1990-2000 For 2000-2008 7.7 1.4 4.1 3.0 Gt 2.3 Gt Taken up by “land”, with a 0.3 Gt residual unaccounted for
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Current Temperature Rise
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Projected Fossil Fuel Emissions: Actual vs. IPCC Scenarios Source: Global Carbon Project [Raupach et al. 2007, PNAS, updated; Le Quéré et al. 2009, Nature Geoscience; International Monetary Fund 2009] Projection 2009 Emissions: -2.8% GDP: -1.1% C intensity: -1.7% Due to Global Recession
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Projected Temperature Rise 2 C is the maximum temperature rise the UNFCCC “recommends” Our current trajectory is closer to 4 C
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Projected Changes in Precipitation Consistent findings across scenarios Increased Asian Monsoon
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