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Global Climate Change: Challenges for Scientists and Scientific Institutions December 6, 2008 Ralph J. Cicerone, President National Academy of Sciences
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OUTLINE Greenhouse Effect Greenhouse Gases from Human Activities Rising Temperatures, Sea Level and Ice Losses World Energy Needs and Fossil Fuels Roles for Scientists and Science Academies Geoengineering ?
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237 105 342 68 169 390 327 90 16 H 2 O, CO 2, O 3
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Calculating the Surface Temperatures of Planets for Venus Actual T e = 730KWRONG! Greenhouse effect and clouds, high pressure S(1 - e for Earth, S = 1368 W/m 2, = 0.3, so we calculate T e = 255K (- 18 ºC or - 32 ºF)WRONG ! Greenhouse effect & clouds are needed for Mars T e = 240 to 250K (large day/night swings) OK Greenhouse effect is very small, low pressure WRONG ! OK !
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Global CO 2 Emission Estimates 1750 - 2005 CITE AS: Marland, G., T.A. Boden, and R. J. Andres. 2007. Global, Regional, and National CO2 Emissions. In Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A.
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Weiss et. al. ALE/GAGE Web site
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Clathrate Decomposition 5? Tg/yr (0.9%) Termites 40 Tg/yr (7.4%) Freshwaters 5 Tg/yr (0.9%) Wetlands 115 Tg/yr (21.3%) Boreal: 20 – 60 Tg/yr Oceans 10 Tg/yr (1.9%) Rice Paddies 110 Tg/yr (18.5%) Biomass Burning 55 Tg/yr (10.2%) Landfills 40 Tg/yr (7.4%) Global Methane Release Rates Coal Mining 35 Tg/yr (6.5%) Gas Production 45 Tg/yr (8.3%) Enteric Fermentation 80 Tg/yr (14.8%) Cicerone & Oremland, 1988Total = 540 Tg/yr
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Frohlich and Lean (2005): Recent analyses of satellite measurements do not indicate a long-term trend in solar irradiance (the amount of energy received by the sun)
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www.giss.nasa.gov/gistemp (updated from Hansen et al., 2001)
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Last 50 Years Surface Temperature Change Based on Linear Trends ( o C)
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Sea Level Change Source: University of Colorado at Boulder http://sealevel.colorado.edu/
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South Cascade Glacier 1955 South Cascade Glacier 2006
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Meltwater stream flowing into a moulin in the ablation zone of the Greenland ice sheet. Accelerations of ice flow in summer are closely related to variations in air temperature and surface melting, and indicate that meltwater quickly travels through 1000 m of ice and enhances basal sliding. These observations reveal a mechanism for dynamic response of ice sheets to climate change. [Photo: R. J. Braithwaite]
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Warming increases mass-loss from self-lubricating ice sheets In places, ice rests on a water-and- mud-lubricated pancake griddle, in other places on a bumpy bedrock waffle iron; these can be mapped through two miles of ice, but job far from done; In places, ice is self-lubricating-- surface meltwater plunges to bottom to make it more slippery, so warming may bring faster flow, but depends on griddle vs. waffle iron character. Zwally et al., 2002, Science
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Where were headed: Heat waves Extreme heat waves in Europe, already 2X more frequent because of global warming, will be normal in mid-range scenario by 2050 Black lines are observed temps, smoothed & unsmoothed; red, blue, & green lines are Hadley Centre simulations w natural & anthropogenic forcing; yellow is natural only. Asterisk and inset show 2003 heat wave that killed 35,000. Stott et al., Nature 432: 610-613 (2004)
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Pre-Industrial 280ppm 380ppm 425 440ppm Present Dangerous Level Global Carbon Cycle Management Anthropogenic Emission 7.2 GtC / y Absorption 3.1 GtC/ y How to control the tap to avoid risk industrialization CO2 in Atmosphere Ocean 2.2 Land 0.9 2ppm/y ex: 2.4-2.8 rise from PI Feedback Adapted from Nishioka, NIES, Japan
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World Primary Energy Consumption, 1970-2030 Quadrillion Btu HistoryProjections 207 244 284 308 347 365 398 463 511 559 607 654 702 Sources: History 1970-1975: Energy Information Administration, International Energy Database, April 22, 2008. History, 1980-2005: Energy Information Administration, International Energy Annual 2005 (http://www.eia.doe.gov/iea). Projections: International Energy Outlook 2007, DOE/EIA-0484(2007) (http://www.eia.doe.gov/oiaf/ieo).
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Solutions Require: Research on Climate Actions for Mitigation Actions for Adaptation
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Climate Change Mitigation and Adaptation Mitigation = Reduce Pace and Amount of Climate Change Caused by Humans Adaptation = Reduce Adverse Impacts on Human Well-being from Climate Changes that Occur
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World Primary Energy Consumption, 1970-2030 Quadrillion Btu HistoryProjections 207 244 284 308 347 365 398 463 511 559 607 654 702 Sources: History 1970-1975: Energy Information Administration, International Energy Database, April 22, 2008. History, 1980-2005: Energy Information Administration, International Energy Annual 2005 (http://www.eia.doe.gov/iea). Projections: International Energy Outlook 2007, DOE/EIA-0484(2007) (http://www.eia.doe.gov/oiaf/ieo).
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International Bodies Are Needed for Consensus Examples: IPCC Reports, IAC Energy Report, United Nations Framework Convention on Climate Change Yet, each country needs its own scientists to evaluate data, to assess scientific understanding.
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Article 2, UN Framework Convention on Climate Change (1992)
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Who Should Define "Dangerous" ? scientists? elected leaders? ____________ ?
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Convene Individual Scientists Analyze and Report on All Issues Interact with Local Leaders Represent the Nation Internationally Science Academies Can:
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©2007 Nature Publishing Group
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Inject Sulfur into Earths Stratosphere ? S gases convert to sulfate particles. Fine particles stay aloft for one year or more, as shown by stratosphere-penetrating volcanoes. Assuming global spreading --- 5 TgS/year could cause 4W/m 2 of cooling cost = $125 billion/year ??. Optical depth of particles = 0.04 (some whitening of sky with reddish, violet sunsets) Current emissions of S from fossil-fuel burning = 50TgS/year Side Effects of Concern:ozone losses ? Other unknown effects? Continuous operations required. (from Crutzen and several other scientists) Modify to Inject only over Arctic Region?
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Geoengineering to Counter Climate Change Motivations Expressed by Proponents Apparent inadequacy of efforts to limit emissions of GGs Hopes for Low-cost engineering interventions Largest Concerns Expressed by Opponents Inadvertent side effects (examples) Unwarranted encouragement for technological fixes will decrease commitment to mitigation efforts. Oceanic acidification will continue.
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Encourage and Formalize Research Peer-reviewed publications in scientific journals. Calculations: State principles, display equations and assumptions, analyze sensitivities and side effects. Suggest experiments. Peer-reviewed research-grant programs. Sessions at major scientific meetings. An Approach to Geoengineering?
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Discourage Implementation: A Moratorium Scientists define criteria and conditions for eventual experiments. Seek small-scale demonstrations and rigorous monitoring, linked with predictive calculations. International teams. Mechanisms for Public Oversight. Withhold participation and endorsement unless/until conditions are met. An Approach to Geoengineering?
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Immediate action with multiple benefits. Energy efficiency would: decrease our dependency on foreign oil improve our national security decrease our trade deficit decrease local air pollution increase our national competitiveness encourage development of new products for global markets decrease household energy costs while also slowing the increases of CO 2 and CH 4 !
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Oceans acidifying as well as warming pH history and business as usual projection Red line is global annual average; blue lines show ocean-to-ocean and seasonal variation. Surface ocean pH has already fallen by 0.1 pH unit. Projected additional changes are likely to have large impacts on corals and other ocean organisms that make skeletons/ shells from calcium carbonate.
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Population, Excessive Consumption, or Technology? CO 2 Emissions = [ Unit Produced ] X [ Person ] X [ Population ] EmissionsUnits Consumed
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