2. A.P. Environmental Science Introduction

3. Global Environmental Science Picture n Four global trends

4. Four Global Trends n Population growth and increasing consumption n Degradation of soils n Global atmospheric changes n Loss of biodiversity

5. 1. Population growth

6. n reached 6 billion about October 12, 1999 n Will reach 7 billion October, 2011 n May reach 10 billion by 2050 n World POPClock World POPClock n Population Connection Population Connection

7. Fig. 1-1, p. 6 Industrial Revolution ? Agricultural revolution Hunting and Gathering Billions of people Time Black Death—the Plague

8. Fig. 1-12, p. 18

9. 1. Population growth n The United States reached 300 million on October 17, 2006 at 3:46 AM.

10. http://www.census.gov/population/ww w/popclockus.html

11. n California now has 38 million, may have 50 million by 2025

12. Population Growth n All people create demands on the earth n Demand tends to increase with affluence “affluenza”

13. Question n “ How can Earth support a near doubling of the population and still increase standards of living ”

14. 2. Degradation of Soils

15. n Fertile soil is the foundation for plant growth and food production n BUT-- soils are being degraded by erosion, overgrazing, development

16. 3. Global Atmospheric Changes

17. u Burning fossil fuels ( oil, natural gas, and coal) has caused increases in global carbon dioxide

18. u CO 2 blocks infrared radiation and therefore traps heat in the atmospheric u resulting in displacement of plants, rise in sea level, changes in climate and weather

19. 4. Loss of Biodiversity

20. u Increasing population and increasing consumption are accelerating conversion of forests, grasslands, and wetlands, etc. to agriculture and urban development

21. Destruction of habitat = destruction of species

22. Biodiversity is important n Mainstay of crops and medicine development n Critical factor in maintaining stability of natural systems n For aesthetic and moral reasons

23. Unifying Themes of Environmental Science

24. 3 Unifying Themes n Sustainability n Stewardship n Sound science

25. Sustainability n Means that a system or process can be continued indefinitely without depleting resources to keep it going n Harvests cannot exceed reproduction rates n Lead to concept of sustainable development

26. Stewardship n Stewards are responsible for earth and its population n Concept originated from environmentalism movement

27. Sound Science n Environmental issues are sometimes embroiled in controversy n One side is science n One side are those who mistrust scientists and their interpretations and motives

28. Understanding science n People need to understand how science is done n Will lead to greater understanding of the issues n Sound science is essential to helping guide us into the 21st century