Advanced Technology Paths to Global Climate Stability: Energy for a Greenhouse Planet. Martin I. Hoffert (1), Ken Caldeira (3), Gregory Benford (4), David R. Criswell(5), Christopher Green (6), Howard Herzog (7), Atul K. Jain (8), Haroon S. Kheshgi (9), Klaus S. Lackner (10), John S. Lewis (12), H. Douglas Lightfoot (13), Wallace Manheimer (14), John C. Mankins (15), Michael E. Mauel (11), L. John Perkins (3), Michael E. Schlesinger (8), Tyler Volk (2), Tom M. L. Wigley (16). Science 298: 981-987, Novemeber 1, 2002 (http://www.sciencemag.org)
Abstract Stabilizing the carbon dioxide–induced component of climate change is an energy problem. Establishment of a course toward such stabilization will require the development within the coming decades of primary energy sources that do not emit carbon dioxide to the atmosphere, in addition to efforts to reduce end-use energy demand. Mid-century primary power requirements that are free of carbon dioxide emissions could be several times what we now derive from fossil fuels (~10^13 watts), even with improvements in energy efficiency. Here we survey possible future energy sources, evaluated for their capability to supply massive amounts of carbon emission–free energy and for their potential for large-scale commercialization. Possible candidates for primary energy sources include terrestrial solar and wind energy, solar power satellites, biomass, nuclear fission, nuclear fusion, fission-fusion hybrids, and fossil fuels from which carbon has been sequestered. Non–primary power technologies that could contribute to climate stabilization include efficiency improvements, hydrogen production, storage and transport, superconducting global electric grids, and geoengineering. All of these approaches currently have severe deficiencies that limit their ability to stabilize global climate. We conclude that a broad range of intensive research and development is urgently needed to produce technological options that can allow both climate stabilization and economic development.
More than a century ago, Arrhenius put forth the idea that CO2 from fossil fuel burning could raise the infrared opacity of the atmosphere enough to warm Earth (1). In the 20th century, the human population quadrupled and primary power consumption increased 16-fold (2). The fossil fuel greenhouse theory has become more credible as observations accumulate and as we better understand the links between fossil fuel burning, climate change, and environmental impacts (3). Atmospheric CO2 has increased from ~275 to ~370 parts per million (ppm). Unchecked, it will pass 550 ppm this century. Climate models and paleoclimate data indicate that 550 ppm, if sustained, could eventually produce global warming comparable in magnitude but opposite in sign to the global cooling of the last Ice Age (4).
The United Nations Framework Convention on Climate Change aims to stabilize greenhouse gas concentrations at levels that avoid “dangerous anthropogenic interference with the climate system (5).” Atmospheric CO2 stabilization targets as low as 450 ppm could be needed to forestall coral reef bleaching, thermohaline circulation shutdown, and sea level rise from disintegration of the West Antarctic Ice Sheet (6). Wigley and colleagues developed emission scenarios to stabilize atmospheric CO2 at 350, 450, 550, 650, or 750 ppm (7). They minimized early emission controls by initially following a business-as-usual scenario that combines economic growth of 2 to 3% per year with a sustained decline of 1% per year in energy intensity (energy use per gross domestic product). Much larger cuts than those called for in the Kyoto Protocol are needed later, because the levels at which CO2 stabilize depend approximately on total emissions. Targets of cutting to 450 ppm, and certainly 350 ppm, could require Herculean effort. Even holding at 550 ppm is a major challenge.
Primary power consumption today is ~12 TW, of which 85% is fossil-fueled. Stabilization at 550, 450, and 350 ppm CO2 by Wigley et al. scenarios require emission-free power by mid-century of 15, 25, and >30 TW, respectively (8). Attaining this goal is not easy. CO2 is a combustion product vital to how civilization is powered; it cannot be regulated away. CO2 stabilization could prevent developing nations from basing their energy supply on fossil fuels (9). Hansen et al. call for reductions in methane and black soot, which also cause warming (10). Such reductions are desirable but do not address fossil fuel greenhouse warming. The Kyoto Protocol calls for greenhouse gas emission reductions by developed nations that are 5% below 1990 levels by 2008 to 2012. Paradoxically, Kyoto is too weak and too strong: Too strong because its initial cuts are perceived as an economic burden by some (the United States withdrew for this stated reason); too weak because much greater emission reductions will be needed, and we lack the technology to make them.
Arguably, the most effective way to reduce CO2 emissions with economic growth and equity is to develop revolutionary changes in the technology of energy production, distribution, storage, and conversion (8). The need to intensify research on such technologies now is by no means universally appreciated. Present U.S. policy emphasizes domestic oil production, not energy technology research (11). Misperceptions of technological readiness also appear in the latest “Summary for Policymakers” by the “Mitigation” Working Group of the Intergovernmental Panel on Climate Change (IPCC): “... known technological options could achieve a broad range of atmospheric CO2 stabilization levels, such as 550 ppm, 450 ppm or below over the next 100 years or more.... Known technological options refer to technologies that exist in operation or pilot plant stage today. It does not include any new technologies that will require drastic technological breakthroughs....” (12)
This statement does not recognize the CO2 emission–free power requirements implied by the IPCC’s own reports (3,8)and is not supported by our assessment. Energy sources that can produce 100 to 300% of present world power consumption without greenhouse emissions do not exist operationally or as pilot plants.
Can we produce enough emission-free power in time? Here we assess the potential of a broad range of technologies aimed at meeting this goal.
...(4 great figures showing the technology approaches and many interesting details)..
Concluding Remarks Even as evidence for global warming accumulates, the dependence of civilization on the oxidation of coal, oil, and gas for energy makes an appropriate response difficult. The disparity between what is needed and what can be done without great compromise may become more acute as the global economy grows and as larger reductions in CO2-emitting energy relative to growing total energy demand are required. Energy is critical to global prosperity and equity.
If Earth continues to warm, people may turn to advanced technologies for solutions. Combating global warming by radical restructuring of the global energy system could be the technology challenge of the century. We have identified a portfolio of promising technologies here—some radical departures from our present fossil fuel system. Many concepts will fail, and staying the course will require leadership. Stabilizing climate is not easy. At the very least, it requires political will, targeted research and development, and international cooperation. Most of all, it requires the recognition that, although regulation can play a role, the fossil fuel greenhouse effect is an energy problem that cannot be simply regulated away.
1, Department of Physics, 2, Department of Biology, New York University, New York, NY 10003, USA. 3, Lawrence Livermore National Laboratory, Livermore, CA94550, USA. 4, Department of Physics and Astronomy, University of California, Irvine, CA92697, USA. 5, Institute of Space Systems Operations, University of Houston, Houston, TX 77204, USA. 6, Department of Economics, McGill University, Montreal, Quebec H3A 2T7, Canada. 7, MIT Laboratory for Energy and the Environment, Cambridge, MA02139, USA. 8, Department of Atmospheric Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. 9, Exxon- Mobil Research and Engineering Company, Annandale, NJ 08801, USA. 10, Department of Earth and Environmental Engineering, 11, Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY 10027, USA. 12, Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA. 13, Centre for Climate and Global Change Research, McGill University, Montreal, Quebec H3A2K6, Canada. 14, Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375, USA. 15, NASA Headquarters, Washington, DC 20546, USA. 16, National Center for Atmospheric Research, Boulder, CO 80307, USA.
The BW summarized the salient facts. I can see from your post you did not even read the article nor look at the graphs of data showing the rise in CO2, etc. Why don't you sight a peer-reviewed scientific journal article purporting that CO2 emissions cause global warming, give the citation and I'll read it, and then we'll debate their data and findings in detail. Up for it? How does your Republican Party propaganda brochure compare to this Science journal review? |
