1. Chapter 11 The Coastal Ocean
Essentials of Oceanography
7th Edition

2. Coastal waters Relatively shallow areas that adjoin continents
Heavily used for commerce, recreation, fisheries, and waste disposal
Experience dramatic changes in salinity and temperature

3. Salinity and temperature in the coastal ocean
Figure 11-1

4. Estuaries Estuaries are partially enclosed coastal bodies of water
Examples of estuaries include:
River mouths
Bays
Inlets
Gulfs
Sounds
Formed by a rise in sea level after the last Ice Age

5. Classifying estuaries by origin
Coastal plain
Fjord
Bar-built
Tectonic
Figure 11-3

6. Tectonic estuary (San Francisco, CA) Fjord estuary (Norway)
Examples of estuaries
Tectonic estuary (San Francisco, CA)
Fjord estuary (Norway)
Figure 11-4

7. Classifying estuaries by water mixing
Vertically mixed
Slightly stratified
Highly stratified
Salt wedge
Figure 11-5

8. Coastal wetlands
Coastal wetlands are saturated areas that border coastal environments
Brackish water conditions
Two most important types of coastal wetlands:
Salt marshes (mid-latitudes)
Mangrove swamps (low latitudes)

9. Coastal wetlands: Salt marshes and mangrove swamps
Figure 11-8

10. The value of coastal wetlands
Coastal wetlands are highly productive areas that serve as fish nurseries for many important species
Effectively filter polluted runoff from land
Problem: are viewed as worthless land, so are often replaced with developments (roads, housing, shopping, etc.)

11. Lagoons
Lagoons are shallow coastal bodies of water separated from the ocean by a narrow strip of land such as a barrier island
Figure 11-9

12. Mediterranean circulation
The Mediterranean Sea experiences high rates of evaporation
Causes inflow of water at the surface and outflow of high salinity water below
Figure 11-11b

13. Pollution in coastal waters
Coastal waters are highly affected by pollution because they are:
Heavily used
Close to sources of pollution
Shallow-water bodies
Not as well circulated as the open ocean

14. Marine pollution: A definition
The introduction by man, directly or indirectly, of substances or energy into the marine environment, including estuaries, which results or is likely to result in such deleterious effects as harm to living resources and marine life, hazards to human health, hindrance to marine activities, including fishing and other legitimate uses of the sea, impairment of quality for use of sea water and reduction of amenities. (World Health Organization)

15. Main types of marine pollution
Petroleum (oil)
Sewage sludge
DDT and PCBs
Mercury
Non-point-source pollution

16. Marine pollution: Petroleum
Oil spills can be caused by:
Tanker accidents
Intentional dumping
Drilling/pumping operations
Figure 11-12

17. Marine pollution: Petroleum
Petroleum is biodegradable
Many pollution experts consider oil to be among the least damaging ocean pollutants
Data from the 1989 Exxon Valdez oil spill shows the recovery of key organisms
Figure 11-13

18. Marine pollution: Petroleum
Various processes act to break up and degrade oil in the marine environment
Figure 11-18

19. Marine pollution: Petroleum
When oil washes up at a beach, it can negatively affect the marine environment
Oil can coat marine organisms and render their insulating fur or feathers useless
Oil on the beach from the Exxon Valdez oil spill, Alaska

20. Marine pollution: Sewage sludge
Sewage sludge is the semisolid material that remains after sewage treatment
Much sewage sludge was dumped offshore until laws restricted sewage dumping
Figure 11-21

21. Marine pollution: DDT
DDT was a widely used pesticide that became concentrated in marine fish
DDT caused brown pelicans and ospreys to produce thin egg shells
Worldwide, DDT has been banned from agricultural use but is still used in limited quantities for public health purposes

22. Marine pollution: PCBs
PCBs are industrial chemicals used as liquid coolants and insulation in industrial equipment such as power transformers
PCBs enter the marine environment through leaks and from discarded equipment
PCBs can accumulate in animal tissues and affect reproduction

23. Marine pollution: Mercury and Minamata disease
Mercury has many industrial uses but is extremely toxic
A chemical plant released large quantities of mercury into Minamata Bay, Japan
Residents who ate highly contaminated fish suffered neurological disease and birth disorders (Minamata disease)

24. Marine pollution: Non-point- source pollution
Non-point-source pollution comes from material washed down storm drains as “poison runoff”
Includes fertilizers, pesticides, road oil, and trash
Figure 11-26

25. Current law regulating ocean dumping
The only substance that is illegal to dump anywhere in the ocean is plastic
Figure 11-27

26. Plastic in the marine environment
Does not biodegrade
Floats
Has high strength
Is ingested by and entangles marine animals
Figure 11-28

27. Essentials of Oceanography 7th Edition
End of Chapter 11
Essentials of Oceanography
7th Edition