A P Environmental Science (APES) What’s the use of a house if you don’t have a decent planet to put it on? Henry David Thoreau Humans and Sustainability: Chapter 1: Environmental Problems, Their Causes and Sustainability Chapter Overview Questions • What are the main themes of this book? • What keeps us alive? What is an environmentally sustainable society? • How fast is the human population growing? • What is the difference between economic growth, economic development, and environmentally sustainable economic development? Chapter Overview Questions (cont’d) • What are the harmful environmental effects of poverty and affluence? • What three major human cultural changes have taken place since humans arrived? • What are the four scientific principles of sustainability and how can we use them and shared visions to build more environmentally sustainable and just societies during this century? Key Concepts • Nature has sustained itself for billions of years by relying on solar energy, biodiversity, and nutrients cycling • Lives and economies depend on energy from the sun, natural resources and natural services (natural capital) Connections in Nature Environment- living and nonliving components that set stage for life Environmental Science- intergrated studies of: • natural science (biology, chemistry, geology) • social science (geography, economics, political science) • humanities (philosophy, ethics) ENVIRONMENTAL SCIENCE Earth's Life-Support System Human Culture Sphere Air (atmosphere) Water (hydrosphere) Population Size Worldviews and Ethics Soil and rocks (lithosphere) Life (biosphere) Economics Politics Ecology and Environmental Science Ecology- study of interaction of organisms with each other and their environment Species- organisms capable of reproducing and producing viable young Ecosystem- defined area within which organisms interact with each other and their environment (smaller slice of a biome) Environmentalism- social movement dedicated to protecting life support systems for all species 3 Goals of Environmental Science • Learn how nature works • Understand how we interact with the environment • Find ways to deal with environmental issues to live more sustainably 3 Principles of Sustainability Long-term sustainability rests on: • Solar energy • Biodiversity • Nutrient (chemical) cycling Solar Energy • Warms planet, necessary for photosynthesis (essential for most life on planet) • Powers indirect forms of solar energy- wind, flowing water (hydroelectric power) Biodiversity • (Astounding) variety of life • Natural systems that support life (biomes) • Natural services such as: topsoil renewal pest control air and water purification Chemical Cycling • Indefinite recycling of chemicals from environment through organisms and back again • AKA nutrient recycling CHECKPOINT 1. What is sustainability and why should we care about it? 2. What are 3 principles nature has used to sustain itself for billions of years? 3 Components of Sustainability • Natural capital • Natural resources • Natural services Natural Capital • Natural resources and natural services • Supports Earth’s diversity • Provided by solar energy ex: ozone layer (resource) + UV protection(service) Natural Resource • Material from environment that meet needs/wants • Vary in renewal time after use: perpetual- continuous supply (sunlight) renewable- days to years for renewal (some fish species) *sustainable yield- highest rate renewable resource can be used without reducing it nonrenewable- exist in fixed stock in terms of human time (energy, metallic minerals, nonmetallic minerals) The Tragedy of the Commons (overexploiting shared renewable resources) described by biologist, Garrett Hardin • Open-access renewable resources: owned by noone, used by anyone (air, open ocean, marine life) • Leads to: “If I don’t use the resource, someone else will and any damage I do to the resource will be too small to matter” • Results in: exploitation and possibly complete degredation of common resource (noone can use it anymore) Example of Tragedy of Commons Imagine a field of grass shared by 6 farmers, each with one cow Each cow currently produces 20 liters of milk per day The carrying capacity of the commons is 8 cows. For each cow above 8, the milk production declines by 2 liters (due to overgrazing, there is less grass for each cow: less grass, less milk!). Total daily milk production for the commons: 120 liters Are the farmers satisfied with 1 cow apiece? Not if they are want more liters of milk (and more profit)! I need a new tractor. Better graze another cow Total daily milk production for the commons: 140 liters (7 cows) We are now at the carrying capacity -- do we stop? Not if I can make a little more profit! Wait! If you can graze another cow, so can I. Total daily milk production for the commons: 160 liters (8 cows) And so... Me too! Me too! Me too! Me too! ...Until there was no more grass for any of the cows The End Natural Services • Natural consequence of energy flow • Provide ecological services • Purify, recycle and detoxify ex: bee pollination of crops rocks, sand purifying stream water marshes controlling flood waters soil formation from eroding rock, decaying organisms Sustainability- Altogether Now CHECKPOINT 1. Create a concept map showing a connection between the following terms: perpetual, renewable and nonrenewable energy. 2. Give examples of each type of resource. Humans and Sustainability • Economic growth- increase in nation’s output of goods, sevices • Gross domestic product (GDP)- annual market value of goods, services produced within nation (measure of economic growth) • Per capita GPD- GPD ÷ total population at midyear (measures economic growth/person) Sustainability and Economic Development Nations are classified as: • More-developed- high average income *19% of population use ≈88% of planet’s resources; produce ≈75% of planet’s waste (US, Canada, Japan, Australia) • Moderately-developed (China, India, Brazil) • Less-developed- middle-low income (poverty) *81% of world’s population (Nigeria, Ethiopia, Somalia) Developed vs Less-Developed Countries Economics: Global View CHECKPOINT 1. What is the difference between GDP and per capita GDP? 2. Distinguish between more-developed and less-developed countries? Ecological Footprint • Ecological footprint- amount of biologically productive land and water required to support an individual and absorb his/her pollution • Per capita ecological footprint- average eco footprint of an individual in an area (calculate your own footprint at www.myfootprint.org/) Ecological Footprint Natural Capital Degradation • unsustainable resource use by wasting, depleting and degrading natural capital • accelerating exponentially • includes: air pollution, aquifer depletion, declining ocean fisheries, species extinction desertification Natural Capital Degradation Ecological Tipping Point • threshold level at which natural capital degradation is irreversible • current tipping points: 1. collapse of some fish populations due to overfishing 2. premature extinction of species due to overhunting, habitat destruction 3. long-term climate change due to burning fossil fuels CHECKPOINT 1. Compare the total and per capita ecological footprints of the United States and China. Use the ecological footprint model to explain how we are living unsustainably. Pollution • Contamination of resource that renders it unsafe • Major types: biodegradable, nondegradable • Results in: 1. disruption of natural life-supports 2. damages life directly 3. create nuisances (unpleasant smells, unwanted noise, etc) Pollution Sources • Point source: single, identifiable sources (drainpipe of a factory, smokestack of a power plant, exhaust pipe of car) • Nonpoint source: dispersed, difficult to identify (pesticides blown into air, runoff of fertilizers from farming areas, litter on Tybee) Dealing with Pollution • Output pollution control/pollution cleanup: cleaning or diluting pollution after it happens • Input pollution control /pollution prevention: reduces or eliminates production of pollutants Problems with Pollution Cleanup 1. Temporary solution (doesn’t address unsustainable use of resource) 2. Often creates pollution in other areas (burning , dumping or burying garbage) 3. Costly 4 Major Causes of Environmental Problems 1. 2. 3. 4. Exponential population growth Unsustainable use of resources Poverty Excluding environmental costs from market prices of goods 5. Conflicting worldview of environmental ethics 1.Population Growth & 2.Unsustainable Resource Use • ≈6.9 billion people on planet • Humanity’s ecological footprint is close to exceeding earths ecological capacity • Can be slowed by economic development, family planning, EDUCATION! Exponential Growth Black Death Hunting and Gathering Agricultural revolution Industrial Revolution 3.Environmental Effects of Poverty and Affluence Poverty: inability to provide for daily needs • affects ≈1 in 5 on planet • prevents choice of environmental protection over survival • results in high rate of natural capital degradation Results of Poverty Environmental Effects of Poverty and Affluence (cont’d) Affluence: lifestyle associated with developed countries which results in: • rapid unsustainable consumption of resources • generation of more pollutants • large ecological footprint • affluenza- addiction to buying more stuff Upside to Affluence • Access to education and technology • Resources to protect natural capital • Resources to reverse some affects of natural capital degredation 4. Prices Vs Value of Natural Capital • Prices of consumer goods and services do not include harmful environmental costs • Government subsidies may encourage depletion and degradation of natural capital • Consumers don’t “feel” the cost of goods to the environment (so they keep wanting more!) 5. Conflicting Worldviews of Environmental Issues Environmental ethics: beliefs about how to treat environmental issues • Planetary management worldview: man is in charge of nature; nature exists to serve man • Stewardship worldview: man has responsibility to ethically manage nature • Environmental wisdom view: nature exists for all species, not just man. Our success depends on knowing how life sustains itself *Aldo Leopold- nature does not belong to man; man belongs to nature CHECKPOINT 1. What is poverty? 2. In what ways do poverty and affluence affect the environment? 3. Explain the problems we face by not including the harmful environmental costs in the prices of goods and services.