theory of Natural Selection some six decades later. The full title of the first edition, which Malthus published anonymously in 1798, was
96 Ehrlich wrote
97 This expansion of Malthus’ ideas beyond issues of food production began in the 1800s, including by British economist David Ricardo, who discussed mineral deposits, and W. Stanley Jevons, who, in 1865, predicted that limits to coal reserves would ultimately halt the country’s economic growth. Within a century Jevon’s predictions of “peak coal” proved correct.
98 Data sources for the World Reserves table are the
99 A single cubic kilometer of average crustal rock contains 200,000,000 metric tons of aluminum, 100,000,000 metric tons of iron, 800,000 metric tons of zinc, and 200,000 metric tons of copper, so mineral exhaustion in the molecular sense is meaningless. D. W. Brooks, P. W. Andrews, “Mineral Resources, Economic Growth, and World Population,”
100 For more on this discussion of mineral exhaustion and the perils of a fixed-stock approach to resource assessment, see John E. Tilton,
101 Matthew R. Simmons,
102 A very detailed analysis comes from the National Institute for Materials Science in Tsukuba, Japan. The authors use the Goldman Sachs BRICs and G6 economic projections discussed in Chapter 2 to project future demand for twenty-two metals. K. Halada, M. Shimada, K. Ijima, “Forecasting of the Consumption of Metals up to 2050,”
103 J. B. Legarth, “Sustainable Metal Resource Management—the Need for Industrial Development: Efficiency Improvement Demands on Metal Resource Management to Enable a Sustainable Supply until 2050,”
104 Unconventional oil is much more difficult to extract and includes materials that are often excavated, like oil shales and tar sands, and high-viscosity oils.
105 Based on their analysis of eight hundred oil fields, including all fifty-four “supergiants” containing five billion or more barrels, the International Energy Agency estimates the world average production-weighted decline rate is currently about 6.7% for fields that have passed their production peak, rising to 8.6% decline by 2030.
106 U.S. Crude Oil Field Production data, U.S. Energy Information Administration, http://tonto.eia.doe.gov/dnav/pet/hist/LeafHandler.ashx?n=pet&s=mcrfpus1&f=a (accessed March 31, 2010).
107 This paragraph drawn from remarks by James Schlesinger, p. 31, summary of the National Academies Summit on America’s Energy Future, Washington, D.C., 2008.
108 This is not to suggest that these areas aren’t or won’t be developed. Turkmenistan, one of the last and most recent countries in the Caspian Sea region to be opened to foreign hydrocarbon development, had no fewer than fifteen petroleum companies seeking to launch activities in 2009, including China National Oil Corporation, Gazprom, Lukoil-ConocoPhillips, Midland Consortium, and Schlumberger, an oil field services company.
109 Drawn from remarks by former U.S. secretaries of energy James Schlesinger and Samuel Bodman to the National Academies Summit on America’s Energy Future, Washington, D.C., 2008.
110 This model projection by the International Energy Agency was revised downward from earlier forecasts to account for the 2008 global economic slowdown. It assumes that oil prices will average $100 per barrel during 2008-2015, then steadily rise to $120 by 2030.
111 D. Goodstein,
112 On average, postpeak oil field decline rates are 3.4% for supergiant fields, 6.5% for giant fields, and 10.4% for large fields,
113 A successful Al Qaeda attack on the Abqaia facilities would have shocked world oil markets, as it handles two-thirds of the Saudi Arabian oil supply. National Academies Summit on America’s Energy Future, Washington, D.C., 2008, p. 9.
114 There are major obstacles to a rapid transition to hydrogen fuel-cell cars, as will be described shortly.
115 Specifically from ozone and particulates. M. Jerrett et al., “Long-Term Ozone Exposure and Mortality,”
116 Only if the electricity supplying the grid comes from clean, renewable sources does the plug-in automotive fleet become pollution- and carbon-free. But depending on the efficiency of the coal- or gas-fired power plant, and how many miles the electricity travels over high-voltage lines, the net balance of this trade-off still generally comes down on the side of plug-in electrics. Also, it is more feasible to recapture pollution and greenhouse gases from hundreds of power station smokestacks than from millions of car tailpipes, particularly with regard to carbon capture and storage (CCS) schemes.
117 Hydrogen is highly reactive and thus quickly combines with other elements, for example with oxygen to make water (H2O).
118 Nearly all electric utility power is made using some outside source of energy to turn a mechanically rotating turbine, to spin a tightly wound coil of copper wire inside of a fixed magnetic field. This produces a flow of electrons in the copper wire that we call electricity. Windmills, hydroelectric dams, coal-fired power plants, and nuclear power plants all use variants of this basic idea to make electricity, the main difference between them being the source of energy used to spin the turbine. For example, heat generated by burning coal or from a controlled nuclear reaction can be used to boil water, producing pressurized steam, which passes over a turbine. Building a dam across a river creates an artificial waterfall, allowing the weight of water to fall upon turbines, and so on.
119 In hydrolysis, electricity is used to split water molecules into pure hydrogen and oxygen. It is a common way to obtain pure hydrogen.
120 In terms of radiative physics, tropospheric water vapor is an even more potent greenhouse gas than carbon dioxide. However, owing to its short residence time in the atmosphere—on average just eleven days—it does not linger long before returning to the Earth’s surface. In contrast, carbon dioxide can persist in the atmosphere for centuries, so its concentration steadily accumulates over time.
121
