The Coastal Ocean

Essentials of Oceanography

Coastal waters

Relatively shallow areas that adjoin continents

Heavily used for commerce, recreation, fisheries, and waste disposal

Experience dramatic changes in salinity and temperature

Salinity and temperature in the coastal ocean

Estuaries

Estuaries are partially enclosed coastal bodies of waterExamples of estuaries include:

River mouthsBaysInletsGulfsSounds

Formed by a rise in sea level after the last Ice Age

Classifying estuaries by origin

Coastal plain

Fjord

Bar-built

Tectonic

Figure 11-3

Examples of estuaries

Fjord estuary (Norway) Tectonic estuary (San Francisco Bay)

Genesis of a Fjord

Coastal wetlandsCoastal wetlands are saturated areas that border coastal environments

Brackish water conditions

Two most important types of coastal wetlands:

1. Salt marshes (mid-latitudes)

2. Mangrove swamps (low latitudes)

Coastal wetlands: Salt marshes and mangrove swamps

Figure 11-8

The value of coastal wetlands

Coastal wetlands are high biological productivity 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.)

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

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

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

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)

Main types of marine pollution

Petroleum (oil)

Sewage sludge

DDT (dichlorodiphenyltrichloroethane) and PCBs (polychlorinated biphenyl)

Mercury

Non-point-source pollution

Marine pollution: Petroleum

Oil spills can be caused by:

Tanker accidents

Intentional dumping

Drilling/pumping operations

Figure 11-12

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

Marine pollution: Petroleum

Various processes act to break up and degrade oil in the marine environment

Figure 11-18

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

Macando Blowout

Gulf of Mexico

Marine pollution: PetroleumDeep-water Horizon Oil Spill (2010) – More appropriately named the Macando Blowout

4.9 million barrels of oil spilled.

Approx. 210,000,000 gallons of oil

Marine pollution: Sewage sludge

Sewage sludge is the semisolid material that remains after sewage treatmentMuch sewage sludge was dumped offshore until laws restricted sewage dumping

Figure 11-21

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

Marine pollution: PCBsPolychlorinated biphenyl

Liver damage, cancer, changes in estradiol

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

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)

Marine pollution: Non-point- source pollution

Non-point-source pollution comes from material washed down storm drains as “poison runoff”

Includes fertilizers (atrizine), pesticides, road oil, and trash

Figure 11-26

Current law regulating ocean dumping

The only substance that is illegal to dump anywhere in the ocean is plastic

Ocean Garbage Patches:

A trash vortex

Approximately twice the size of Texas

At least 100 feet deep

Plastic in the marine environment

Plastic:Does not biodegrade

Floats

Has high strength

Is ingested by and entangles marine animals

Figure 11-28

In groups of two or three:

Design, draw & label the following:An estuary

Movement of water in/out of the estuary from a large body of water.

Some example life forms that would live in the area

3 sources of pollution & the consequences or resolutions to the pollution.

By yourself:1. Draw or describe a made up organism that can be found

in the following zones:a. Euphotic

b. Disphotic

c. Aphotic

d. Hadal

2. At least one must be benthic.

3. The following characteristics/strategies must be included: DSL, counter shading, chromatophores, camouflage, euro/stenothermal, euro/stenohaline, meroplanktonic.

BellworkChange 10 to 25% of the water in your tank. Fill up the tank so there is no visible water line!

If you are not helping with your tank you need to be working on the following:

In groups no larger then 3:

Create a single chart/drawing that includes all of the following in their appropriate locations:

Epipelagic, mesopelagic, bathypelagic, abyssopelagic, hadal, deep scattering layer, estuary, lagoon, barrier island, coastal waters, continental shelf, small-eyed fish, large-eyed fish, blind fish.