mitigating near-term climate change: black carbon and short-lived greenhouse gases john c. topping,...
TRANSCRIPT
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
“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
20th Century GHG Emissions
21st Century CO2 only
Warming Effect During 21st CenturyBusiness as Usual Emissions Scenario, Assumes Some Improvement in Energy Efficiency
Credit: MacCracken 2009
20th Century GHG Emissions
21st Century CO2
Warming Effect During 21st CenturyBusiness as Usual Emissions Scenario, Assumes Some Improvement in Energy Efficiency
Credit: MacCracken 2009
20th Century GHG Emissions
21st Century CO2
Warming Effect During 21st CenturyBusiness as Usual Emissions Scenario, Assumes Some Improvement in Energy Efficiency
Credit: MacCracken 2009
20th Century GHG Emissions
21st Century CO2
Warming Effect During 21st CenturyBusiness as Usual Emissions Scenario, Assumes Some Improvement in Energy Efficiency
Credit: MacCracken 2009
20th CBC
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 of100 years
Over Period of
20 years
1 Tonne of Methane vs. 1 Tonne of CO2
War
min
g E
ffec
t
Years12
20 100
MethaneCO2
Warming Effect From GHGs and BC
Sources: IPCC AR4 (2007) , MacCracken and Moore (2008), Ramanathan and Carmichael (2008)
Emission Type Warming Effect in 2005 over Pre-Industrial (watts / m2)
Atmospheric Lifetime
Carbon Dioxide 1.56 Centuries-Millennia
Methane 0.86 12 years
N2O 0.14 114 years
CFC / HCFC 0.28 100-1000 years
CO / VOC(O3 precursors)
0.27 CO – months, VOC – hours(O3 – weeks)
Black Carbon 0.44-0.9 1-2 weeks
Total 3.55 – 4.01
Tropospheric OzoneFormed 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
MethaneAtmospheric 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 heatStays 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 HimalayasEnormous regional increase in warming effectGlobally 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
annuallyReduced outdoor air pollution, which kills 0.8M
annually
20th Century GHG Emissions
21st Century CO2 only
Warming Effect During 21st CenturyBusiness as Usual Emissions Scenario, Assumes Some Improvement in Energy Efficiency
Credit: MacCracken 2009
20th CBC
20th Century GHG Emissions
21st Century CO2 only
Warming Effect During 21st CenturyAggressive Reductions in both GHGs and Black Carbon
Credit: MacCracken 2009
Near-Term Changes in Warming EffectBlack Carbon is Critical to Reducing Near-Term Warming
Business as Usual
Aggressive Reductionsin BC and GHGs
Credit: MacCracken 2009
Business as Usual
Not part of Kyoto Protocol or any carbon valuation system
Models for poor-rich country cooperation Clean cookstove effortsManila jeepneys
Developed countries must continue their BC reductionsStrengthen diesel standards Increasing industrial energy recyclingActing aggressively through Arctic Council to slash BC
emissions affecting Arctic
Black Carbon Policy
Ways to Reduce BC
• Diesel Particulate Traps
• Jeepney Retrofits
• Biodegradable Motor Oils
• Vessel Emissions
• Industrial Energy Recycling
• Cleaner Cookstoves
• Suppression of Arctic Forest Fires
Tickell Interactive Network
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.
Global Alliance for Clean Cookstoves
Photo Credit: Sunil Lal Photo Credit: E+Co Photo Credit: GTZ Photo Credit: Nigel Bruce
