An Introduction to Environmental Science Chapters 1, 2, and 3

1. An Introduction to Environmental ScienceChapters 1, 2, and 3 Check out study tips at the end of the power point

2. Environment: the total of our surroundings • All the things around us with which we interact: • Living things (biotic factors) • Animals, plants, forests, fungi, etc. • Nonliving things (abiotic factors) • Continents, oceans, clouds, soil, rocks • Our built environment • Buildings, human-created living centers • Social relationships and institutions

3. Humans and the world around us • Humans change the environment, often in ways not fully understood • We depend completely on the environment for survival • Increased wealth, health, mobility, leisure time • But, natural systems have been degraded • i.e., pollution, erosion and species extinction • Environmental changes threaten long-term health and survival

4. Natural resources: vital to human survival Natural resources = substances and energy sources needed for survival • Renewable resources: • Perpetually available: sunlight, wind, wave energy • Renew themselves over short periods: timber, water, soil • These can be destroyed • Nonrenewable resources: can be depleted • Oil, coal, minerals

5. Environmental science is not environmentalism • Ecology • The science that deals with the distribution and abundance of organisms and the interactions among them and other organisms. • Environmental science is the study of: • How the natural world works • How the environment affects humans and vice versa • The pursuit of knowledge about the natural world • Scientists try to remain objective • Environmentalism • A social movement dedicated to protecting the natural world

6. Environmental science: how does the natural world work? Environment  impacts  Humans • It has an applied goal: developing solutions to environmental problems • An interdisciplinary field that incorporates: • Natural sciences: information about the world • Environmental Science programs • Social sciences: values and human behavior • Environmental Studies programs

7. The nature of science • Science: • A systematic process for learning about the world and testing our understanding of it • A dynamic process of observation, testing, and discovery • The accumulated body of knowledge that results from this process • Science is essential • To sort fact from fiction • Develop solutions to the problems we face

8. Applications of science leads to Policy decisions and management practices Technology Restoration of forest ecosystems altered by human suppression of fire Energy-efficient methanol-powered fuel cell car from DaimlerChrysler

9. The scientific method • A technique for testing ideas with observations • Assumptions: • The universe works according to unchanging natural laws • Events arise from causes, and cause other events • We use our senses and reason to understand nature’s laws

10. Controlled Experiments • Controlled Experiments contain experimental and control groups. • The experimental group is the group in the experiment that is identical to the control group except for one factor and is compared with controls group. • The control group is the group in the experiment that serves as a standards of comparison with another group to which the control group is identical except for one factor.

11. Manipulative experiments yield the strongest evidence But, lots of things can’t be manipulated Experiments test the validity of a hypothesis

12. Experiments test the validity of a hypothesis • Natural tests show real-world complexity • Results are not so neat and clean, so answers aren’t simply black and white

13. Correlations (natural test) • If question is impossible or unethical, scientists test predictions by examining correlations or natural experiments. • Correlation is the linear dependence between two variables.

14. With enough data, a paradigm shift –a change in the dominant view – can occur

15. DRY MIX is an acronym to help you remember how variables are plotted on a graph. • D = dependent variableR = responding variableY = graph information on the vertical axisM = manipulated variable I  = independent variableX  = graph information on the horizontal axis

16. Independent Variable or Manipulated Variable is what you are testing. It is what causes things to change as you make changes to it. Some people nickname it the I-do variable. • Dependent Variable or the Responding Variable is the effect and it may or may not change. It is observed during as well as at the end of the experiment.

18. Global human population growth • More than 6.7 billion humans • Human population growth has shaped our relationship with natural resources. • Current rate of population growth has slowed but is still growing at 1.23% a year. • Estimated population for 2050 is 9.2 billion • Population growth in developing • countries is increasing 15 times • faster than developed countries • By 2050, 97% of growth will be • in developing countries

19. How Many People Can the Earth Support? We do not know how long we can continue increasing the earth’s carrying capacity for humans without seriously degrading the life-support system for humans and many other species.

20. PERIODS OF HUMAN HISTORY AND POPULATION GROWTH • Hunter-Gatherer • Agriculture revolution • Industrial revolution • Technology revolution (globization)

21. POSITIVE OUTCOMES Population was usually small Expert Knowledge of the Natural World NEGATIVE OUTCOMES High infant mortality rate Overharvested animals to point of extinction Altered ecosystems by distribution of seeds Hunter-Gatherers (earliest humans)Survived by hunting animals and gathering wild plants. They were often nomadic.

22. POSITIVE OUTCOMES More food due to growing crops Support larger populations Higher standard of living and life expectancy Formed villages, towns, etc. NEGATIVE OUTCOMES Cleared land for farming-destruction of habitat and native wildlife Loss of soil fertility and increasing soil erosion More people in concentrated areas contributes to waste, pollution, diseases Power struggle for ownership of resources Agricultural Revolution (10,000-12,000 years ago)Shift in human culture whereas, hunter-gatherers settled into agricultural communities. Domestication of animals and cultivation of plants occur. Main energy sources animal power (some water and wind power)

23. POSITIVE OUTCOMES Mass production of useful and affordable goods. Increased agriculture production. Higher standard of living and life expectancy Lower infant mortality Moderate to high rate of population of growth NEGATIVE OUTCOMES Increased use and dependency of nonrenewable resources Increased air pollution, water pollution Increased amount of waste products. Soil depletion and degradation; Habitat destruction; Loss of biodiversity Industrial Revolution (mid 1700’s until 1900’s)Human cultural shift from animal power to the use of fossil fuels and machinery. (Shift from renewable to nonrenewable resources)

24. POSITIVE OUTCOMES Computer generated models of Earth systems Increased technology surveying and sensing environmental systems The ability to respond to environmental issues/problems more effectively NEGATIVE OUTCOMES Information overload Globalized economy can increase environmental degradation Globalized economy can decrease cultural diversity Information/Globalization Revolution (1950’s until present)Humans are currently in process of social, economic, and environmental changes. This is characterized by sharing and integrating technology worldwide. Development of world-wide communication systems ( telephone, radio, computers, TV, satellites, Internet,)

25. How Long Can the Human Population Keep Growing? Can the human population grow indefinitely? Population growth has slowed but we do not know how long we can continue without overshooting earth’s carrying capacity for humans. No population, including humans, can continue to grow indefinitely.

26. Studying human populations Demography is the study of the characteristics of populations, especially human populations. Demographers study the historical size and makeup of the population. They study properties that affect population growth such as economics and social structure.

27. Unequal distribution of wealth and resources around the world influences environmental problems. The U.N. generally classifies countries as either developed or developing. Economic differences among countries

28. lower average incomes simple agriculture-based communities rapid population growth African countries like Kenya and Ethiopia Indonesia India Characteristics of Developing Countries CHARACTERISTICSCOUNTRIES

29. higher incomes slower population growth diverse industrial economies stronger social support. Characteristics of Developed Countries CHARACTERISTICSCOUNTRIES • United States • Canada • Japan • Countries of Western Europe

30. Almost all environmental problems can be traced back to two root causes: • The human population in some areas is growing too quickly for the local environment to support. (POPULATION GROWTH) • People are using up, wasting, or polluting many natural resources faster than they can be renewed, replaced, or cleaned up. (COMSUMPTION PRACTICES)

31. Problems associated with consumption practices • To support the higher quality of life, developed countries are using much more of Earth’s resources. • More of a problem in Developed Countries. • This rate of consumption creates more waste and pollution per person than in developing countries.

32. Problems associated with rapid population growth • There may not be enough natural resources for the everyone to live a healthy, productive life. • Many problems in Developing Countries result from population growth rate. • In severely overpopulated regions, forests are stripped bare, topsoil is exhausted, and animals are driven to extinction. • In these areas, malnutrition, starvation, and disease can be constant threats.

33. The wealth gap and population growth cause conflict • The stark contrast between affluent and poor societies causes social and environmental stress • The richest 20% use 86% of the world’s resources • Leaves 14% of the resources for 80% of the world’s people to share • Tensions between “haves” and “have-not’s” are increasing

34. How Long Can the Human Population Keep Growing? Thomas Malthus and population growth: In 1798, Malthus a British economist, hypothesized that the human population tends to increase exponentially while food supply increases at a much slower rate. So far, Malthus has been proven wrong. Food production has increased exponentially due to technology advances. Many people believe that technological advances have allowed humans to avoid environmental resistance faced by other populations therefore increasing the carrying capacity for humans.

35. Thomas Malthus and human population • Thomas Malthus • Wrote An Essay on the Principle of Population • Population growth must be restricted, or it will outstrip food production • Starvation, war, disease

36. How Long Can the Human Population Keep Growing? Advocates for slowing population growth believe that because we now fail to provide the basic needs for 1 out of 5 people, how can we support future growth. They are concerned about increased death rates because declining health and environmental degradation. Also the increasing ecological footprint may increase resource use and further degradation.

37. Neo-Malthusians • Paul and Anne Ehrlich, The Population Bomb (1968) • Population growth has disastrous effects leading to famine and conflict by the end of the 20th century

38. “The Tragedy of the Commons” • In his essay, ecologist Garrett Hardin argued that the main difficulty in solving environmental problems is the conflict between the short-term interests of the individual and the long-term welfare of society. • The example he used was the commons, or the areas of land that belonged to the whole village.

40. “Tragedy of the Commons” • Hardin’s point can be applied to our modern commons, natural resources. • Humans live in societies, and in societies, we can solve environmental problems by planning, organizing, considering the scientific evidence, and proposing a solution. • The solution may be to override the short-term interests of the individual and improve the environment for everyone in the long run.

41. Avoiding mistakes made by past civilizations.The lesson of Easter Island: people annihilated their culture by destroying their environment. Can we act more wisely to conserve our resources? http://channel.nationalgeographic.com/series/explorer/3829/Overview#tab-Videos/06769_00

42. The “ecological footprint” • Wackernagel and Rees • The environmental impact of a person or population • Amount of biologically productive land + water • for raw materials and to dispose/recycle waste • Overshoot: humans have surpassed the Earth’s capacity We are using 30% more of the planet’s resources than are available on a sustainable basis!

43. Ecological footprints are not all equal • The ecological footprints of countries vary greatly • The U.S. footprint is almost 5 times greater than the world’s average • Developing countries have much smaller footprints than developed countries • www.myfootprint.org

44. Population growth affects the environment • The IPAT model: I = P x A x T x S • Our total impact (I) on the environment results from the interaction of population (P), affluence (A) and technology (T), with an added sensitivity (S) factor • Population = individuals need space and resources • Affluence = greater per capita resource use • Technology = increased exploitation of resources • Sensitivity = how sensitive an area is to human pressure • Further model refinements include education, laws, ethics

45. Natural Capital =Natural Resources + Natural Services • Natural Resources are materials and energy essential to humans. • Natural services include biochemical cycles (carbon, hydrogen, nitrogen, phosphorus) and energy transfer. • Living sustainable means living off the interest of natural capital.

46. Culture and worldview • Our relationship with the environment depends on assessments of costs and benefits • Culture and worldview also affects this relationship • Culture = knowledge, beliefs, values, and learned ways of life shared by a group of people • Worldview = a person’s or group’s beliefs about the meaning, purpose, operation, and essence of the world Culture and worldview affect our perception of the environment and environmental problems

48. Expanding ethical concern • Why have we expanded our ethical concerns? • Economic prosperity: more leisure time, less anxieties • Science: interconnection of all organisms • Non-western cultures often have broader ethical domains • Three perspectives in Western ethics • Anthropocentrism = only humans have rights • Biocentrism = certain living things also have value • Ecocentrism = whole ecological systems have value • Holistic perspective, stresses preserving connections

49. Western ethical expansion

50. The preservation ethic • Unspoiled nature should be protected for its own inherent value • John Muir (right, with President Roosevelt at Yosemite National Park) had an ecocentric viewpoint