Introducing Environmental Science and Sustainability

1. Introducing Environmental Science and Sustainability 1

2. Overview of Chapter 1 • Human Impacts on The Environment • Population, Resources and the Environment • Sustainability • Environmental Science • Addressing Environmental Problems

3. The Environment (Earth) • Life has existed on earth for 3.8 billion yrs • Earth well suited for life • Water over ¾ of planet • Habitable temperature, moderate sunlight • Atmosphere provides oxygen and carbon dioxide • Soil with essential minerals for plants

4. Human Impacts on Environment- Population • Earth’s Human Population is at 6.9 billion • Growing exponentially • Expected to add several billion more people in 21st century

5. World Population Clock • http://www.census.gov/main/www/popclock.html

6. Population • 1 in 4 people live in extreme poverty • Cannot meet basic need for food, clothing, shelter, health • Difficult to meet population needs without exploiting earth’s resources

7. Gap Between Rich and Poor • Highly Developed Countries (HDC) • Complex industrialized bases, low population growth, high per capita incomes • Ex: US, Canada, Japan

8. Gap Between Rich and Poor • Less Developed Countries (LDC) • Low level of industrialization, very high fertility rate, high infant mortality rate, low per capita income • Ex: Bangladesh, Mali, Ethiopia

9. Types of Natural Resources

10. Overpopulation • People overpopulation • Too many people in a given geographic area • Problem in many developing nations • Consumption overpopulation • Each individual in a population consumes too large a share of the resources • Problem in many highly developed nations, US in particular

11. Consumption • Consumption • Human use of materials and energy • People in HDCs are big consumers • Unsustainable Consumption • Occurs when the level of demand on a country’s resources damages or depletes the resource enough to reduce the quality of life for future generations • Caused by overpopulation and/or overconsumption

12. Ecological Footprint • The average amount of land, water and ocean required to provide that person with all the resources they consume

13. Ecological Footprint • Humans have an ecological overshoot

14. Ecological Footprint Comparison

15. Environmental Impact Affluence per person I = P A T Environmental effect of technologies Number of people IPAT Model • Measures 3 factors that affect environmental impact (I)

16. Environmental Sustainability

17. Environmental Sustainability • The ability to meet current human need for natural resources without compromising the needs of future generations • Requires understanding: • The effects of our actions on the earth • That earth’s resources are not infinite

18. Day 2 Notes

19. Tragedy of the Commons • Garrett Hardin (1915–2003) • Solving Environmental Problems is result of struggle between: • Short term welfare • Long term environmental stability and societal welfare • Common pool resources • Garrett used Common Pastureland in medieval Europe to illustrate the struggle

20. Sustainable Development- Systems Concept • Economic development that meets the needs of the present generation without compromising future generations

21. Environmental Science • An interdisciplinary study of human relationship with other organisms and the earth • Biology • Ecology • Geography • Chemistry • Geology • Physics • Economics • Sociology • Demography • Politics

22. Earth System and Environmental Science • System • A set of components that interact and function as a whole • Global Earth Systems • Climate, atmosphere, land, coastal zones, ocean • Ecosystem • A natural system consisting of a community of organisms and its physical environment

23. Earth Systems and Environmental Science • Negative feedback • Change triggers a response that counteracts the changed condition

24. Feedback • Positive feedback • Change triggers a response that intensifies the changing condition

25. Scientific Method

26. Controls and Variables in Experiment • Variable • A factor that influences a process • The variable may be altered in an experiment to see its effect on the outcome • Control • The variable is not altered • Allows for comparison between the altered variable test and the unaltered variable test

27. Five Steps to Addressing An Environmental Problem • Five steps are idealistic • Case Study: Lake Washington

28. Assessing Environmental ProblemCase Study: Lake Washington • Large, freshwater pond • Suburban sprawl in 1940’s • 10 new sewage treatment plants dumped effluent into lake • Effect = excessive cyanobacteria growth that killed off fish and aquatic life

29. Assessing Environmental ProblemCase Study: Lake Washington • Scientific Assessment • Aquatic wildlife assessment done in 1933 was compared to the 1950 assessment • Hypothesized treated sewage was introducing high nutrients causing growth of cyanobacteria • Risk Analysis • After analyzing many choices, chose new location (freshwater) and greater treatment for sewage to decrease nutrients in effluent

30. Assessing Environmental ProblemCase Study: Lake Washington • Public Education/Involvement • Educated public on why changes were necessary • Political Action • Difficult to organize sewage disposal in so many municipalities • Changes were not made until 1963! • Evaluation • Cyanobacteria slowly decreased until 1975 (gone)

31. Assessing Environmental ProblemCase Study: Lake Washington • Results