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Climate Change

Climate Change. The Scientific Consensus International Treaties. The greenhouse effect. Large molecules allow solar radiation in, but not out Understood since 19 th century Goldilocks phenomenon: Earth is “just right” Greenhouse gases

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Climate Change

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  1. Climate Change The Scientific Consensus International Treaties POLS 422

  2. The greenhouse effect • Large molecules allow solar radiation in, but not out • Understood since 19th century • Goldilocks phenomenon: Earth is “just right” • Greenhouse gases • CO2, H2O, CH4, O3 (natural and anthropogenic) • CFCs, N2O (anthropogenic) • Difference between warm intervals & ice ages: 6°C POLS 422

  3. Fundamental Climate Questions • Are CO2 concentrations increasing? • Yes. • Short-term measurements • Long-term: ice core samples • Is this caused by humans? • Yes. 180-280 ppm is natural • Since industrialization, increased to 380 ppm • Is climate changing? • Prior to FCCC, unclear • Since 1996, IPCC consensus is yes. • More dramatically than models predict POLS 422

  4. IPCC • Background: From UNEP & WMO to UNGA • Predictions • 1995: "The balance of evidence suggests that there is a discernible human influence on the global climate.” [+1.0-3.5 ° C] • 2001: "There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities.” [+1.4-5.8 °C] • 2007: “There is very high confidence that the net effect of human activities has been one of warming. Evidence shows that natural systems are being affected.” [+1.4-8.6 °C] POLS 422

  5. IPCC predictions • CO2 doubling this century >> 1.5°- 8.6° C warming • Sea level rise: + 40-80 cm in 21st C • Could be much larger if Greenland or Antarctic ice sheets melt • More frequent and intense tropical storms • Katrina as indicator of the future • “Climate surprises” inevitable • Ex: Ocean’s thermohaline circulation system POLS 422

  6. FCCC (1992) • Objective: “stabilize atmospheric concentrations of GHGs at safe levels” • Principles • “Common but differentiated responsibility” • Precautionary principle • Cost-effectiveness • Obligations • Annual GHG Inventories • Annex I (IC’s): return GHG emissions to 1990 levels by 2000 (nonbinding) • Annex II (western IC’s): financial assistance to DCs POLS 422

  7. Kyoto Protocol (1997) • 6 GHGs covered: CO2, CH4, N2O, PFCs, HFCs, SF6 • Annex I: differentiated GHG reductions totaling 5% from 1990 levels by 2008-12 • U.S. - 7%; EU -8% Aus, Iceland +10% • 5 ways to meet obligations • Simply reduce GHG emissions • Enhance sinks (forests) • Emissions trading among Annex I parties • Joint implementation in Annex I parties • Clean Development Mechanism (DCs) POLS 422

  8. What Kyoto means: 3 versions • Meaningful action • Annex I emissions projected to rise 30% by 2010 over 1990 levels • Symbolic politics • Loopholes will prevent real cuts in GHGs • Stage is set for deeper reductions • Meaningless gesture • To stabilize GHG concentrations, an immediate 70% reduction in GHG emissions is required • …or 90% by 2030 POLS 422

  9. After Kyoto • 2001: U.S. withdrawal • Bonn surprise (July 2001) • Bush withdrawal galvanized action • Decisions on capacity building in DCs & E. Europe, tech. transfer, joint implementation • Adaptation fund pledged by EU & other ICs • $410 million/year • Russia ratified, bringing Kyoto into force in 2005 • Current negotiations: post-2012 reductions POLS 422

  10. Beyond International Law • Voluntary initiatives • Pew Center: Business Environmental Leadership Council • Public utilities: Seattle City Light • Individuals: Carbon offsetting • Local initiatives • ICLEI: 500+ cities & counties in 67 countries, representing 300 million people • U.S. cities: Nickels’ initiative > 50 million • US governors suit against utilities thrown out • CA: 1990 levels by 2020; 80% below by 2050 • Emissions trading with U.K. POLS 422

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