1. Environmental Problems Global Warming Pollution Overfishing

2. Global Warming: Causes “Green house effect” Green house gases (chloroflourocarbons =CFCs, methane, CO 2, water vapor) Increasing CO 2 –Deforestation & burning fossil fuels

3. Fig. 15-31, p. 326

5. Fig. 15-32, p. 326 Global Avg Surface Temp – Relative to 1951-80 mean

7. Global Warming: Marine Impacts

8. Fig. 15-33, p. 327 The North Pole 1996

9. The Maldives in the Indian Ocean – 80% pop. live only 1m above sea level

10. Global Warming: Marine Impacts Sea-level Rise (4-10 inches last century) –Coastal habitats, corals Coral Bleaching Habitat shifts Fresh water lens Circulation patterns

11. Marine Pollution The introduction into the ocean by humans, substances that changes the physical, chemical or biological environment

12. Marine Pollution Many forms –chemicals, sewage, solid waste, sediment, heat Impact of a pollutant depends on quantity, toxicity of the pollutant to each organism, & its affect on the environment Bioamplification – even small amounts of pollutants can have large effects

14. Fig. 15-23, p. 321 Rachel Carson: Silent Spring 1962 – misuse of pesticides

15. PCBs – Poly chlorinated Biphenyls used in hundreds of industrial and commercial applications –(including electrical, heat transfer, and hydraulic equipment; as plasticizers in paints, plastics and rubber products; in pigments, dyes and carbonless copy paper and many other applications) More than 1.5 billion pounds of PCBs were manufactured in the U.S. prior to cessation of production in 1977. 1976 the Toxic Substances Control Act (TSCA) that included prohibitions on the manufacture, processing, and distribution in commerce of PCBs.

16. Marine Pollution Eutrophication –Excess nutrients in water also lead to problems HABs Oxygen depletion

17. Fig. 15-22, p. 321

18. Overfishing When so many fish have been harvested, there are not enough left to breed and replenish the species 45% fish stocks known are overfished

19. Overfishing When so many fish have been harvested, there are not enough left to breed and replenish the species 45% fish stocks known are overfished

20. Fig. 15-10, p. 311

23. Overfishing: Causes Hard to estimate maximum sustainable yield –Must know pop. size, growth & reproduction, life span Models are oversimplified –Don’t always consider competition, schooling behavior, size of fish caught, when they are caught

24. Bykill or By-catch Other species are accidentally caught Drift nets – banned in 1993 “Dolphin-Safe Tuna” Turtle exclusion devises (TEDs)

26. Fig. 15-7a, p. 309

27. Fig. 15-7b, p. 309

29. Fig. 15-26, p. 323

30. What Can Be Done? Education Rational activism – even at the individual level

31. Ozone Depletion: Causes Ozone = three atoms of oxygen Forms naturally in upper atmosphere CFCs attack & deplete ozone layer 4% decrease in US since 1969 50% decrease over poles

32. Ozone Depletion: Marine Impacts Increasing UV levels Decrease in phytoplankton productivity Mortality of surface zooplankton (larvae)

33. Fig. 15-29, p. 325