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Outline

Outline. Acknowledgements. Physics of the pendulum. Personal context for the talk. Limits to Growth (1973, 1992, 2004): summary. Canadian situation: Managing without Growth (2008) Evidence that the models show the correct trends. Nuclear weapons: review, where we are now.

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Outline

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  1. Outline • Acknowledgements. • Physics of the pendulum. • Personal context for the talk. • Limits to Growth (1973, 1992, 2004): summary. • Canadian situation: Managing without Growth (2008) • Evidence that the models show the correct trends. • Nuclear weapons: review, where we are now. • What we can do.

  2. Beauty of Physics : predictive power from a few basic ideas. Force = mass x acceleration gives Time for 1 swing of pendulum as l = length of pendulum = 4.3 m g = 9.8 m/s2 T = 4.2 s, independent of its mass.

  3. Positive and negative feedback, sustainability, limits to growth. Positive feedback: increases the quantity of interest. Negative feedback: decreases the quantity of interest. Sustainability: inputs equal outputs, now and into the future. Limits to growth

  4. I started at Trent in 1973. 1962 Rachel Carson's Silent Spring: First public concern over chemical pollution. 1963 Limited Test Ban Treaty: No atmospheric nuclear bomb tests; first global treaty against pollution. US-USSR Cold War at its height. 1966 Paul Ehrlich's The Population Bomb: Modern recognition of finite size of the world. 1973 Meadows et al.Limits to Growth: First attempt to model the interactions of population, resources, pollution, .. 1973 Trent's first course on environmental problems (Physics & Chemistry)

  5. Militarism Environmental degradation Global economic inequity Broader Context: Three closely related problem areas in the world today. • Cost of Militarism (Stockholm International Peace Research Institute, 2009 data) • The world spends more than $1.5 trillion /year on militarism = $1.1 million/minute or • $225 per person /year.“ This is an increase of 49% since 2000. • Reducing military expenditures of core countries (~$500 billion/yr) by less than 10% • each year would pay the costs, for everyone in poorer countries, of • Basic education • Water and sanitation • Basic health and nutrition • Education/programs for birth control • (UN Development Programme, 2001) • Military operations cause 6 to10% of global air pollution and contribute significantly to global warming. (World Watch Institute 2000).

  6. Limits to Growth 1973, 1992, 2004 • Modelled global relationships among 5 variables: population, non-renewable natural resources, industrial outputs (consumer, agricultural, health, more industrial capacity, ...), food production, and pollution. • Designed to predict global trends, not to make exact predictions re numerical values or dates or specific effects. • Exponential growth makes advance planning critical • Exponential growth = Growth depends on the quantity already present. • E.g. toxic algae on a pond doubles every day. First noticed when it covers 1% of the pond. 1, 2, 4, 8, 16, 32, 64, 128%. If wait until 50% coverage to attack the problem, only 1 day left. • “Slow” at start, but accelerates. • Limits - cultivable land • - agricultural yield per unit of land • - non-renewable resources (oil, minerals) • - ability of the earth to absorb pollution

  7. Speak to your neighbours. Which of the following do you think would have the biggest effect on global sustainability? • (a) population • (b) non-renewable natural resources • (c) industrial outputs (consumer, agricultural, health, ...) • (d) food production • (e) pollution. • Which of the above do you think we can affect most easily?

  8. Erosion loops: self-increasing feedback. Temp rise in North > snow melts earlier > less snow to reflect sunlight > more heat absorbed by earth

  9. Possible response modes of the model global carrying capacity Time Example: Population

  10. 2004 Standard run, Doubled non-renewable resources Business as usual & better extraction technology

  11. One stable model • Assumes in 2002: • Accepted goal of 2 children/family • Goal of adequate global standard of living: 10% more than world average in 2000. • New technologies improve (to 4%/yr per unit of output): resource use, land yield, pollution abatement, as needed and with 20-year implementation period. • (Over 100 years, this reduces pollution per unit of output by 95%. Similar gains for land yield and efficiency of resource use.)

  12. Stable model Policies implemented in 2002 Policies implemented in 1982

  13. Time Scales(1992 book) Why government and the market will not provide a solution by themselves.

  14. Overall conclusions of model • Unregulated exponential growth leads to overshoot and collapse. • If you raise one limit, you encounter another soon, and sometimes several. The world does not run out of land or food, "it runs out of the ability to cope". We have to work on all aspects at once (discussion). • Costs skyrocket as we approach a limit: it costs far more per barrel to process tar sands oil than conventional oil. It costs much more to remove the last 20% of a pollutant from a smokestack. • Time delays in response (e.g., time to implement new technology or policy) result in overshoot (or undershoot) and oscillation or collapse. • "The market is blind to the long term & pays no attention to sources or sinks until they are almost exhausted, which is too late to act." • Therefore, we (our governments) cannot rely on markets or individual goodwill to solve the problems; governments must regulate and rely on innovation and entrepreneurship to accomplish this efficiently.

  15. A sustainable society is probably still possible without reductions in population, industrial output, or quality of life, if we act now. • Sustainability would not freeze in inequities in society; all people must be at a comparable and acceptable standard of living for the world to be sustainable. • A sustainable society does not mean zero growth or a stagnant society. New goods and services would continue to be developed, but net material investment would be zero. Conditions for a Sustainable Society (Herman Daly) • Renewable resources cannot be used up faster than they are generated. (Can’t cut forest faster than new ones grow.) • Non-renewable resources cannot be used up faster than renewable substitutes are developed. (Bio-oils to replace crude oil, for lubrication.) • Pollution emissions cannot exceed the absorptive capacity of the environment.

  16. Canada: Peter Victor, Managing Without Growth (2008) 213 177 136 122 36

  17. Canada: Peter Victor, Managing without growth (2008) 169 78 56 46 48 Reduced poverty by transfer of $ from rich to poor through taxes. Improved productivity (output per person) AND high employment, through a shorter workweek NOT more production.

  18. Evidence that the Limits to Growth models are reasonable • The models fit current data reasonably well; e.g, 1972 model predicted 2002 population and food output. • The predicted limits are now visible. Climate change (pollution) ~ Limit for runaway climate change. http://en.wikipedia.org/wiki/File:Carbon_Dioxide_400kyr.png http://data.giss.nasa.gov/gistemp/graphs/

  19. Depletion of Non-renewable Resources: "Peak Oil" http://www.theoildrum.com/node/6169 Gabriella, CEO of Petrobras, (2009): "The world needs oil volumes the equivalent of one Saudi Arabia every two years to offset future world oil decline rates."

  20. Depletion of Non-renewable Resources: Minerals (D. Cohen, New Scientist, 2007)

  21. SPECIES EXTINCTIONS International Union for the Conservation of Nature - in 2004 calculated that the rate of extinction had reached 100-1,000 times that suggested by the fossil records before humans. 17,300 species are considered under threat. E.g., in the past 20 years, about 70% of all butterfly species in Britain have shown signs of decline. About 28% of plant species and 54% of bird species also declined in areas studied over long periods. Science (2004) and Juliette Jowit, Guardian newspaper, March 2010.

  22. Renewable Resources: “Global ecological footprint”(WWF Living Planet Report 2010) Footprint: Land and water area the human population requires to produce the resources it consumes and to absorb its wastes, using prevailing technology.

  23. Nuclear Weapons (has largely disappeared from the public discourse) Militarism Environmental degradation Global economic inequity The Hiroshima bomb killed (15,000 tons of TNT) ~ 100,000 people over about 3 days. Modern hydrogen bombs (~ 1 million tons of TNT) are typically 70 times more powerful.

  24. Fig. 4 . Global firepower of nuclear weapons in terms of World-War II firepower, 2001 The one dot in centre = firepower of WW II = 3 MT. Each square = 50 WW II's. Circle at upper left = 24 MT = firepower on 1 Trident sub = 8 WW II's. Dots in two squares = destroy all large and medium cities in world. Total ~ 2000 WW II's http://www.tridentploughshares.org/article1071

  25. Number of nuclear weapons in the world (Fed'n American Scientists Feb 2011) US & Russia each have ~2000 weapons on high alert. MAD = Mutually Assured Destruction = 200

  26. USA and Russia stockpile of nuclear weapons, 1945-2005 (http://en.wikipedia.org/wiki/Nuclear_arms_race) MAD 2011

  27. LONG-TERM EFFECTS • Nuclear radiation: cancer, leukemia, genetic damage. From 1945 to 1984, 2500 people per year were still dying prematurely from the radiation from Hiroshima and Nagasaki bombs of 1945. • 2. Nuclear winter (from an all-out war): Science Dec. 1983 (Climate model) • Reduction of sunlight to about 5% of normal, blocked by the sooty smoke from • burning cities. • Darkness and sub-freezing temperatures would last for several months, down to -23oC. • A global effect, as the smoke would circulate over most of the world. • Result: if the war was in early spring, then be no summer that year, so no crops • for > 1 yr. People surviving the initial radiation would soon have no food. • 3. Effects from regional conflict of one hundred 15-kT (small) warheads on cities. Science Mar. 2007 • - For example, India vs. Pakistan: 22 million immediate dead in these countries. • (+ Gwynne Dyer: Climate Wars, 2008, from water conflict) • - Global cooling: e.g., 20 fewer frost-free days in Canadian prairies, would devastate wheat production.

  28. Recent Progress in Disarmament • 1996 Comprehensive Test Ban Treaty (CTBT). • Bans all NW tests, to stop the development of new weapons, and eventually eliminate all weapons as they must be tested periodically. • As of March 2011, nine of the 44 “nuclear-capable” states had not ratified the treaty: • signed but not ratified: China, Egypt, Indonesia, Iran, Israel and the United States • not signed: India, North Korea and Pakistan • But … no USA or Russian tests since 1992.

  29. Under Obama (elected Nov. 4, 2008) • - Feb 2009, cut out all funding for The Reliable Replacement Warhead program, a favourite of the Bush government. • April 2010. Signed 10-year New START treaty with Russia (Strategic Arms Reduction Treaty): • - reduce deployed nuclear weapons by a further 30%. Both sides can retain 1550 deployed warheads, but removed warheads don't have to be destroyed. • - limits missile launchers and heavy bombers to 800, half of the previous treaty. • - 18 on-site inspections/year allowed. • - ratified by Russia and USA governments; effective Feb. 5, 2011. • April, 2010. New Nuclear Posture Review: "The NPR is a pragmatic policy document that combines maintaining a strong nuclear arsenal, modest reductions in nuclear weapons, nonproliferation efforts, and a vision of a world free of nuclear weapons." (FAS). It also renounces the development of any new nuclear weapons by the USA. • The situation is improving, but with even 3000 weapons on high alert there is still a danger of an accidental launch.

  30. Militarism Environmental degradation Global economic inequity • General conclusions from Limits to Growth: • We have to act now. • All aspects must be addressed at once. • You and I have to take active control over our future. The marketplace or governments will not initiate the process. • Individual goodwill is not enough; we need broad grassroots support to force government change. • A sustainable future can be reached with an acceptable standard of living for all, and no reduction in population. • This is an enormous challenge, but also an incredible opportunity and motivation to create the world we all want. Business as usual is not acceptable.

  31. What can we do? (From Limits to Growth) • Visioning – we have to imagine where we want to go, in broad terms, before we can make progress towards sustainability. • Networking – we can’t do it alone. We need the support of others, moral, technical, organizational, political, …. • Truth-telling – we must reframe the discourse. • Not: A warning about the future is a prediction of doom. • But: A warning about the future is a recommendation to follow a different path. • Learning – The best path forward is uncharted. We need inform ourselves, do our best, and learn from our mistakes. • Loving – To avoid collapse, we must see ourselves, others and nature as part of an integrated global ecosystem. We must contribute as individuals but one individual can't do everything. Work close to the heart, cultivate community, and trust others to do the rest.

  32. WHAT CAN WE DO? • - Keep informed • - Become involved: - Contribute time or $ to an environmental/peace/social justice group. • - Make the environment an election issue. • SOME PETERBOROUGH ENVIRONMENTAL ORGANIZATIONS • - OPIRG (Ontario Public Interest Research Group) • - Council of Canadians • - SAGE (Safe and Green Energy) • - Transition Town • SOME PETERBOROUGH AND CANADIAN PEACE ORGANIZATIONS • Project Ploughshares, http://www.ploughshares.ca/ (Kawartha Ploughshares in Peterborough, Dr. Joyce Barrett 743-0241). • Physicians for Global Survival, http://www.pgs.ca/ • Ceasefire, http://www.ceasefire.ca/ • Science for Peacehttp://scienceforpeace.sa.utoronto.ca/ (Main office at U. of Toronto); encourages student groups. • SOME PETERBOROUGH SOCIAL JUSTICE ORGANIZATIONS • - Peterborough Partnership Council on Immigrant Integration • - Community and Race Relations Committee • - Jamaica Self-Help • - ......

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