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Dennis Meadows
Economics and Limits to Growth: What’s Sustainable? Dennis Meadows at The Population Institute Washington, DC October 6, 2009 1 The Reference Scenario Original Report Today Industrial Output Population Pollution Resources Food 2 Main Insights from the Scenario • In 1972 we expected another 40-80 years of growth. • All our scenarios showed growth ending in the period 2010-2050. • The preponderant mode was overshoot and decline, not gradual slowing within a limit. • Changes in technology may delay the end of growth by a few years, but they do not avoid it, and they do not avoid the decline. • Social changes are essential for the attractive futures. • What are today considered to be problems are actually symptoms. The real problem is physical growth in material and energy flows pressing against the limits of a finite planet. 3 Main Points of My Speech • Growth has continued until we are now past sustainable levels. • The global society will change more over the next 20 years than in the past 100. Design policies for what is coming, not what has been. • The main forces for change will be climate change and resource scarcity - especially fossil fuels and water. • The end of growth does not result from total depletion, but from rising capital costs. • The most important scarcity is the absence of a longerterm perspective. 4 World Population 5 Industrial Production 6 Index of World Metals Use 7 “Sind die Menschen noch zu retten?” Die Zeit, 16.11.06 If current trends of overfishing and pollution continue, .. all seafood faces collapse by 2048. By the middle of the century … no fewer than 7 billion people in 60 countries may be faced with water scarcity. Human beings and the natural world are on a collision course. .. Fundamental changes are urgent…. - more than 1,600 scientists, including 102 Nobel laureates, from 70 countries (Ignoring climate change) “could create risks of major Disruption to economic and social activity… on a scale Similar to those associated with the great wars.” Stern Review October 2006 8 One Indicator of Overshoot 9 Other Indicators of Overshoot 10 The Sequence of Objections • 1970s: There are no limits. • 1980s: There are limits, but they are distant in time. • 1990s: The limits are near, but they are irrelevant, since they will be dealt with by the market. • 2000s: The market is not adequate, but new technologies will let us evade the limits without requiring that we stop growth. 11 Capital Cost of Discovery C o s t 0 Fraction of Resource Remaining 1 12 Capital Cost of Abatement C o s t 0 Fraction of Sink Remaining 1 13 Energy Return on Investment 14 15 The Time of Greatest Stress • Most people assume that the major global difficulties would occur after the end to growth. • This is not correct. • The globe’s population would experience the most stress prior to the peak, as pressures mount high enough to neutralize the enormous political, demographic, and economic forces that now sustain growth. • We are in the early phases of that period now. 16 CO2 Concentration 17 Four Factors Determine the Amount of CO2 Emissions CO2 Emissions Number Units of Energy of x Capital x Required per x People Per Person Capital Unit Efficiency Demography Cultural Norms Fraction of Energy from Fossil Fuels Solar Energy Technology © Dennis Meadows; 2007 18 A Problem Better -------> Time Horizon Desired Actual Now Next Evaluation Future 19 Easy Problems Better -------> Action #1 Desired Actual Action #2 Now Next Evaluation Future 20 Difficult Problems Better -------> Action #1 Action #2 Desired Actual Now Next Evaluation Future 21 Relying on Present Net Value to Choose Assumes: • All consequences of an action are known • All consequences can be expressed in monetary units; they are commensurate • We are the ones entitled to pick the interest rate • Maximizing financial benefits is the goal of society • Current mistakes can be corrected by paying some cost in the future Every single one of these assumptions is false for the issue of climate change!! 22