Lecture 36Are there solutions to global warming?1) Energy alternatives2) Cutting emissions - a political issueThe Energy Issuecurrently: • global, primary energy production is 12 TW (i.e. 12 * 1012 Watts = 12 TeraWatts)• 85% from fossil fuels = 10 TW… this is the problem, equivalent to ~ 6 Gt C/yrneed: • to stabilize CO2 at 550 ppm (double pre-industrial) - where impacts are perhapsmanageable • to accomodate rising population (to 10 billion) and economic progress• 10-30 TW emission-free energy by 2050Further info on world energy:Hoffert et al (2002), Science, 298, 981-987 [www.sciencemag.org >search]Technical solutions• improving efficiency a few TW, safe, feasible, immediate• carbon sequestration But how, exactly?• renewable Safe, requires capital investment-wind power-tidal power-geothermal power-biomass power (i.e. from fast-growing plants with zero netCO2 input because the plant growth uses CO2)-solar energy promising, currently expensive• nuclear fission a few TW; radioactive waste issue• nuclear fusion Not yet feasible.Energy AlternativesImproving efficiency• Fuel efficient cars; Mass transit• Fuel cell hydrogen* cars - up to 70% efficient(*assuming hydrogen is made using renewableenergy, not oil/coal (which is the plan in the Bush Administration hydrogen fuel initiative))• Conservation via building codes• US could reduce emissions by 10-40% at a net savings(according to study by Rubin et al (1992) Science, 257, 261-266)• 1975-2000, US reduction in energy intensity saved energy equivalentto 3 times total oil importsCarbon emission sequestration• Remove CO2 at source with organic solvents (active areaof research by energy companies in anticipation of future regulation)• Huge challenge: a typical 500-MW coal-fired power station emits 10,500tonnes CO2 /day.• Recover CO2 and store in deep ocean/underground(relatively impractical and a potential time-bomb if it were to escape)Energy AlternativesRenewable energy• hydropower (close to saturation)• solar, wind, geothermal currently <1% of global energy• In 2001, wind provided 24 GW (i.e. 1/400 of total global energy)but is growing very rapidly (24% per year in 2001)•10 TW from biomass requires land area similar to ALLpresent agriculture• 10 TW solar requires an area 500 km x 500 km = 250,000 km2vs. 3 km2 presently. Massive but could be done. Could be used to generate H2.Possible leap in technology: ultra-efficient plastic solar cells.• Wind power limited in location. But does supply 10-25% ofpower in Germany, Spain, Denmark. Could supply ~10%of world’s power according to recent estimates.Energy Alternativesnuclear fission at 10 TW, only 6-30 years of proven uranium reserves waste disposal and security issues nuclear fussion no working technology at present prospects are murky geoengineering or climate engineering reflect about 2% of sunlight with stratospheric particles or space mirrors technical feasibility not well known unintended consequences very likely BUT: Publicly-funded energy R&D in the EU and US declined 35%, 1985-1998.US private sector investment in energy research fell 53% over same period.PolicyBottom line: Global warming is a global problem and can only besolved through international cooperation.Discussed implementation issues concerning emissionsreductions; discussed national progress.Conference of the Parties(COP 9), Milan, Dec 2003Failure to agree between Europe and USAon how tough the treaty should beConference of the Parties(COP 6), The Hague, 2000Kyoto Protocol set targets for CO2 emissions forindustrialized nations. Signed by USA but not ratified.Currently, President G.W. Bush neither supportsratification nor enforcement of CO2 emissionreductions.Conference of the Parties (COP 3),Kyoto, 1997UN Framework Convention on Climate Change(UNFCCC) - signed by USA.Currently, a total of 188 signatories; 6 observersRio de Janeiro, 1992(http://unfccc.int/)ResultConferenceThe Kyoto ProtocolTargeted CO2, CH4, N2O, SF6 and some CFC substitutesProposed reductions in GHG emissions:5.2% below 1990 levels for whole world within the period 2008-20128% ” ” ” EU ” ” ”7% ” ” ” USA ” ” ”Countries joining also agreed to other measures, e.g.,:• inventory of national sinks and emissions of GHGs• formulate national programs to mitigate climate changePossible mechanisms (not specified in the treaty): -carrot & stick: fossil fuel taxes, energy conservation tax breaks- US govt idea of emissions trading based on quotasMakes a 20-30% reduction from “business as usual” in 2008-2012Kyoto developmentsBush Administration objections:- developing countries are exempt, including India and China- “incomplete state of scientific knowledge of the causes of, and solutions to,global climate change”- the Kyoto Protocol “would cause serious harm to the US economy”Status of emissions:2000: EU average GHG emissions were 3.5% below 1990 levels2000: US GHG emissions were 13% higher than in 1990 - makes Kyoto even lesslikely to be joined by USA1990-2020: China global contribution to emissions expected to go from 7% to 25%To enter into international law, Kyoto needs1) to be ratified by >55 countries [ done: 104 govts by 2003: EU, Japan, China,..]2) that they emit at least 55% of the industrialized world’s CO2(not yet done, requires Russia to ratify, given that USA won’t)Other countries argue for a “precautionary principle” (‘better safe than sorry’) inthe face of climate uncertainty, analogous to buying insurance. Critics note thesecurity gain for the US if it were to reduce its dependence on foreign oil.Kyoto continued…Dec 2003: Putin decides not to join KyotoIncreasing energy exports to USA are thought to be a large factor(environmentalists blamed Bush Admin for influencing Putin’s decision)Yesterday: March 9, 2004: Putin tells Canadian PM he will ratify KyotoProspect of EU investment in Russian energy industry may be a factor.2004: Russia’s emissions have fallen 32% since 1990 due to poor economy.Scientists all agree, however, that the Kyoto Protocol is not enoughto stop global warming (you can work this out: Fig. 16-14 in textbook).It amounts to ~0.15°C GAAST decrease. Kyoto is analogous to the MontrealProtocol, which was insufficient to stop ozone depletion and had to have numerousamendments to bring ozone levels back to 1970 values by 2100.Conclusion: Currently, global warming has no solution