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Mitigating Near-Term Climate Change: Black Carbon And Short-Lived Greenhouse Gases. John C. Topping, Jr . Leaders Preserving Our Future: Pace and Priorities on Climate Change World Preservation Foundation • London • 3 November 2010.
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Mitigating Near-Term Climate Change: Black Carbon And Short-Lived Greenhouse Gases John C. Topping, Jr. Leaders Preserving Our Future: Pace and Priorities on Climate ChangeWorld Preservation Foundation • London • 3 November 2010
“On the basis of the increasing pace of global warming, including the potential for an abrupt acceleration, … the risk appears to be increasing that a tipping point leading to ‘dangerous,’ or perhaps even catastrophic change could surprise us in the years ahead.” Dr. Michael C. MacCracken
Warming Effect During 21st Century Business as Usual Emissions Scenario, Assumes Some Improvement in Energy Efficiency 21st Century CO2 only 20th Century GHG Emissions Credit: MacCracken 2009
Warming Effect During 21st Century Business as Usual Emissions Scenario, Assumes Some Improvement in Energy Efficiency 21st Century CO2 20th Century GHG Emissions Credit: MacCracken 2009
Warming Effect During 21st Century Business as Usual Emissions Scenario, Assumes Some Improvement in Energy Efficiency 21st Century CO2 20th Century GHG Emissions Credit: MacCracken 2009
Warming Effect During 21st Century Business as Usual Emissions Scenario, Assumes Some Improvement in Energy Efficiency 20th C BC 21st Century CO2 20th Century GHG Emissions Credit: MacCracken 2009
Successful Climate Change Solutions Require Moving Beyond CO2's Challenges • Century long atmospheric lifetime • CO2 emission inertia bound to global energy and agriculture systems • Difficult to achieve North-South consensus • Uncertainty in CO2 regulation Slashing emissions of black carbon and short-lived GHGs must be part of any credible strategy for climate stabilization
Rethinking How We Compare GHGs • Common Metric: 1 tonne of methane = 22 tonnes of CO2 • Possible New Metric: 1 tonne of methane = 75 tonnes of CO2 What’s the difference? (Hint: Methane only lasts 12 years)
Rethinking How We Compare GHGs • Common Metric: 1 tonne of methane = 22 tonnes of CO2 • Possible New Metric: 1 tonne of methane = 75 tonnes of CO2 Over Period of 100 years Over Period of 20 years
1 Tonne of Methane vs. 1 Tonne of CO2 Warming Effect Methane CO2 20 100 12 Years
Warming Effect From GHGs and BC Total 3.55 – 4.01 Sources: IPCC AR4 (2007) , MacCracken and Moore (2008), Ramanathan and Carmichael (2008)
Tropospheric Ozone • Formed as a secondary product of other emissions • By oxidation of methane, CO, and VOCs in the presence of NOx • Once formed, lasts 20 – 24 days • Warming Effect is ~ 0.3 W/m2 • 18% of CO2 effect
Methane • Atmospheric concentrations rising after several years of stability • Lasts 12 years in atmosphere • Warming Effect is ~ 0.86 W/m2 • Just over 50% of CO2 effect • Win-Win opportunities to reduce methane
Black Carbon (Soot) • Dark-colored type of aerosol / particulate matter (PM) • Absorbs sunlight and heat • Stays in atmosphere for only 1 – 2 weeks • Atmospheric Warming Effect is 0.44 – 0.9 W/m2 • 28 – 55% of CO2 effect • Decreased snow albedo in Arctic and Himalayas • Enormous regional increase in warming effect • Globally averaged, is an additional 0.1 – 0.2 W/m2 • Harmful to human respiratory health
Regional Effects • “ Tropospheric ozone and BC snow albedo effect contribute substantially to rapid warming and sea ice loss in the Arctic ” - James Hansen et al. 2005 • Arctic Warming Since 1890 (Shindell et al. 2009) • Black carbon: 0.5 – 1.4˚C • Trop. Ozone: 0.2 – 0.4˚C Shindell estimates that combined sulfate decrease and BC increase caused 75% of direct Arctic warming over past 30 years
Benefits from Black Carbon Reduction • Atmospheric loading and warming influence will drop as emissions drop • Acute decrease in Arctic warming • Reducing certain BC emissions will result in: • Reduced indoor air pollution, which kills 1.9M annually • Reduced outdoor air pollution, which kills 0.8M annually
Warming Effect During 21st Century Business as Usual Emissions Scenario, Assumes Some Improvement in Energy Efficiency 20th C BC 21st Century CO2 only 20th Century GHG Emissions Credit: MacCracken 2009
Warming Effect During 21st Century Aggressive Reductions in both GHGs and Black Carbon 21st Century CO2 only 20th Century GHG Emissions Credit: MacCracken 2009
Near-Term Changes in Warming Effect Black Carbon is Critical to Reducing Near-Term Warming Aggressive Reductions in BC and GHGs Business as Usual Business as Usual Credit: MacCracken 2009
Black Carbon Policy • Not part of Kyoto Protocol or any carbon valuation system • Models for poor-rich country cooperation • Clean cookstove efforts • Manila jeepneys • Developed countries must continue their BC reductions • Strengthen diesel standards • Increasing industrial energy recycling • Acting aggressively through Arctic Council to slash BC emissions affecting Arctic
Ways to Reduce BC • Diesel Particulate Traps • Jeepney Retrofits • Biodegradable Motor Oils • Vessel Emissions • Industrial Energy Recycling • Cleaner Cookstoves • Suppression of Arctic Forest Fires
Global Alliance for Clean Cookstoves • A new public-private partnership led by the United Nations Foundation seeking to create a thriving global market for clean cookstoves in the developing world in order to: • Save lives by reducing exposure to cookstove smoke; • Empower women through productive enterprises associated with stove use, distribution, and production; • Improve livelihoods by reducing disease, freeing time and saving money (which can be used for the purchase of food, medicine, or school fees) and many other social benefits (e.g. clean kitchen, extra time, etc. • Combat climate change by mitigating emissions of black carbon and greenhouse gases, reducing rate of deforestation • Advance Millennium Development Goals related to poverty, health, gender equality, and the environment. Photo Credit: Sunil Lal Photo Credit: E+Co Photo Credit: GTZ Photo Credit: Nigel Bruce