1. Oceanography

2. I. Introduction to Oceans
A. Oceanography – the study and exploration of the world’s oceans.
B. Formation of the ocean waters – water vapor and condensation
of vapor as rain in the
ocean basins

3. II. Properties of Ocean Water
A. Composition of Ocean Water
1. H2O is 96.5 %
2. other elements is 3.5%
3. salinity – dissolved salt content of a body of water

4. II. Properties of Ocean Water
B. Temperature of Ocean Water
1. as temperature increases, density decreases
2. surface temperature – from 2OC (Arctic) to 28OC (equator)
3. subsurface temperature – from 1OC to 3OC
4. thermocline – zone where there is a sharp difference in temperature between surface and deeper water.

5. II. Properties of Ocean Water
C. Pressure – pressure increases as the ocean depths increases
D. Color – natural color is blue, but can be affected by pollutants or microscopic plants

6. III. Oceans – a continuous body of saltwater that covers approximately 70% of the Earth
A. PACIFIC – the largest, deepest, covers 1/3 of the Earth’s surface, contains approximately ½ of the Earth’s water.
B. ATLANTIC – second largest, contains Mediterranean, Caribbean and North Seas, shallower than Pacific and Indian

7. III. Oceans
C. INDIAN - deeper than the Atlantic, shallower than the Pacific
D. ARCTIC – surrounds the geographic North Pole

8. IV. Life in the Ocean
A. Plankton – drifting organisms in aquatic environments (marine and freshwater). The base of the food web in these environments
1. phytoplankton – plant plankton – example – diatoms
2. zooplankton – animal-like plankton example- protists, crustaceans

9. IV. Life in the Ocean
B. Nekton – organisms that swim in the ocean freely.
examples – larger fish, squid, sea turtles, whales

10. IV. Life in the Ocean
C. Benthos – community of organisms that live on, in, or near the ocean floor
examples – crabs, coral, starfish, clams, sea anemones
1. benthic environment – region near or at the bottom of a pond, lake, or ocean, including organisms that live there
2. pelagic environment – ecological realm that includes the entire ocean water column

11. Threats to the Ocean
The oceans are huge but are becoming increasingly more polluted.
Overfishing is also destroying fish populations.

12. V. Marine Ecosystems
Includes: estuaries, coral reefs, oceans, and polar ecosystems
Marine ecosystems contain dissolved _____.
In oceans, lack of water is not a problem. Therefore, the types of organisms present are dependent upon __________, sunlight available, and ___________.
salt
temperature
nutrients

13. Estuaries

14. Estuaries
An ecosystem where _____ _____ from rivers and streams mixes with _____ _____ from the ocean.
Estuaries contain plenty of light and nutrients which support large populations of plants and animals.
Plants and animals that live in estuaries are able to tolerate variations in ________ because the _____ content of the water varies as the fresh and salt water mix.
fresh
water
salt
water
salinity
salt

15. Threats to Estuaries
Estuaries provide harbors, access to the ocean, and connections to rivers. As a result, many of the world’s largest cities are built on estuaries.
Because of this, many estuaries have become polluted.

16. Coral Reefs

17. Coral Reef
limestone
Coral reefs are __________ islands in the sea that are built by coral animals called polyps.
Thousands of species of plants and animals live in the cracks and crevices of coral reefs, making coral reefs among the most ________ ecosystems on Earth.
Corals can only live in _____ salt water where there is enough ______ for photosynthesis. Therefore, coral reefs are only found in shallow, tropical seas.
diverse
warm
light

18. Threats to Coral Reefs
If the water surrounding a reef is too hot or cold, or if fresh water drains into the water surrounding a reef, corals have trouble producing limestone.
If the water is too muddy, too polluted, or too high in nutrients, algae that live within the corals will die or grow out of control and smother the corals.
Oil spills, sewage, pesticide, and silt runoff have all been linked to coral reef destruction.

19. Polar Ecosystem

20. Polar Ecosystems
The ice-covered polar caps can be considered marine ecosystems because nearly all food is provided by phytoplankton in the ocean.
The ______ Pole is in the Arctic Ocean and the ______ Pole is in Antarctica.
________ provides the main source of food at both poles.
North
South
Plankton

21. Threats to Polar Ecosystems
Oil extraction, tourism, and garbage are the worst threats to the polar ecosystems.
Conservationists want these areas to become world wildlife refuges.

22. Upwelling refers to deep water that is brought to the surface.
Areas of upwelling are created by surface winds that pull water away from an area. This deficit of water on the surface invites water to come up from deeper regions.

23. To understand upwelling, you must be familiar with how the Coriolis Effect affects ocean surface currents. The Coriolis Effect acts on moving water, because it is not attached to the rotating Earth. As water flows over the rotating earth, it appears to deflect to the right in the Northern Hemisphere and the left in the Southern.

24. The deep water that surfaces in upwelling is cold; by looking at Sea Surface Temperature maps we can identify cool upwelled water versus hotter surface water.

25. Upwelled water also contains nutrients (nitrate, phosphate, silicate) and dissolved gases (oxygen and carbon dioxide) that are not utilized at depth because of a lack of sunlight. Now on the surface, these nutrients and gases help to fuel photosynthesis by small algae called phytoplankton.

26. Phytoplankton photosynthesize using specialized color pigments called chlorophyll. Thus, “Ocean Color” maps are another way to identify areas of upwelling. Where on this ocean color map are high phytoplankton concentrations?

27. Ecological and Economic effects of upwelling:
Upwelling leads to more phytoplankton
More phytoplankton leads to more fish
More fish lead to commercial fishing jobs and to more seafood

28. Even though upwelling areas account for only 1% of the ocean surface, they support 50% of the worlds fisheries.

29. Phytoplankton come in many shapes and forms
Phytoplankton come in many shapes and forms. Collectively they form the base of oceanic food webs.
Without upwelling many of the world’s fisheries would not thrive.

30. Some climatic events can reduce upwellings.~
El Nino

31. Along Peru’s coast, an El Nino event decreases the coastal winds
Along Peru’s coast, an El Nino event decreases the coastal winds. Thus the upwelling from below is slowed.
An El Nino condition results from weakened trade winds in the western Pacific Ocean near Indonesia, allowing piled-up warm water to flow toward South America.

32. What is La Niña?
La Niña is characterized by unusually cold ocean temperatures in the Equatorial Pacific, compared to El Niño, which is characterized by unusually warm ocean temperatures in the Equatorial Pacific.

33. VI. Instruments of Investigation
SCUBA – Self-Contained Underwater Breathing Apparatus. Tanks of compressed air strapped on a diver’s back and connected by hoses to a mouthpiece for breathing
SONAR – Sound Navigation And Radar. Methods of mapping the ocean floor by transmission and reflection of sound waves

34. Instruments of Investigation (cont.)
C. Geostationary operational Environmental Satellites (GOES) orbit the Earth at 22,000 miles. They are highly advanced observation platforms supplying detailed imagery of the Earth’s oceans

35. Instruments of Investigation (cont.)
D. Underwater Laboratories – The Aquarius Underwater Laboratory is the only undersea laboratory dedicated to marine science operating in the world. Aquarius provides life support systems that allow scientists to live and work underwater, in reasonably comfortable living quarters, with sophisticated research capabilities

36. Instruments of Investigation (cont.)
E. Deep ocean submersibles – Over the last few decades, engineers have developed technologies capable of meeting the many challenges that the deep sea imposes upon explorers.

37. VIII. Waves and Wave Action
A. Causes – wind and earthquakes
B. Characteristics of Waves
1. crest – highest point of a wave
2. trough – lowest point of a wave
3. wavelength – distance between
2 adjacent wave crests or wave
troughs

38. VIII. Waves and Wave Action
4. wave frequency – the number of
waves that pass a point in a
certain amount of time
5. wave period – time between the
passage of two wave crests (or
troughs) at a fixed point

39. VIII. Waves and Wave Action
6. wave height – vertical distance
between crest and trough of a
wave
7. breaker – high wave crest that
has been pulled down by gravity
8. surf – area between the breaker
zone and the shore
9. white caps – wave crests breaking
into white foam

40. VIII. Waves and Wave Action
10. swells – formation of long wavelength surface waves more stable than normal wind waves and formed by storms
11. deep water waves – waves that move in water deeper than ½ their wavelength
12. shallow water waves – waves that reach water shallower than ½ their wave height

41. VIII. Waves and Wave Action
C. Tsunami – a great sea wave caused especially by undersea earth movement or volcanic eruption

42. VIII. Waves and Wave Action
D. storm surge – an offshore rise of water often associated with a low pressure weather system, typically tropical cyclones
E. undertow – the current beneath the surface that sets seaward or along the beach when waves are breaking on the shore
F. longshore current – an ocean current that move parallel to the shore

43. IX. Tides
A. Tidal range – the vertical difference between high and low tides
1. high tides – occur twice a day, when the ocean water bulges as a result of the gravitational pull of the overhead moon
2. low tides – occur twice a day, when the two areas of the earth are not experiencing high tide

44. IX. Tides
B. Spring Tide – exceptionally high and low tides that occur at the time of the full and new moons, when the sun, earth, and moon are approximately aligned
C. Neap Tide – times when the difference between high and low tide are minimized. Occur during quarter moons

45. X. Currents and Climates
A. Surface currents – Horizontal movement of seawater in the ocean
1. are driven by winds and can affect movement to a depth of several hundred meters
2. either cool or warm the air above it influencing the climate of the land near the coast (example – Gulf Stream)
B. Ocean Currents
Deep Currents

46. At the shoreline
Water becomes shallow, wave height increases because wave length decreases
Waves become steeper, then collapse (breakers)

47. Wave refraction Close to coast, water gets more shallow
Waves are slowed down
If waves arrive at an angle, one part is slower than the rest
Causes waves to bend = wave refraction

48. Waves arriving at bays are slow (deposition)
At headlands, faster (erosion)

49. A sequence of features is produced as headlands are degraded
Sea cliffs
Waves erode base -undercutting

50. Headlands may be eroded back leaving a remnant (stack)

51. Longshore drift Waves arrive at a coast at an angle (swash)
Backwash returns at 90 degrees
Sand is moved along the beach = longshore drift or longshore current

52. Result of longshore drift and a lot of sediment
Coastal deposition
Result of longshore drift and a lot of sediment
= produces extensions of deposit from the shoreline

53. May grow across a bay (baymouth bar)
spit = curved extension
May grow across a bay (baymouth bar)
May link an island to the main land (tombolo)

54. Types of Coastline Submergence and emergence changes coastlines
Pocket beaches

55. Emergent coast Uplifted land surface
Coastal landforms are found above present sea level
a wave-cut platform when elevated - uplifted marine terrace

56. Barrier Island Coasts Occur on low lying coasts with gentle gradients
BARRIER ISLANDS - low ridges of sand built by waves
behind the islands are lagoons
shallow water with tidal deposits
TIDAL INLETS - gaps between the islands

57. Oceanography – Think about it!
You will be given a scenario which you will read. You will then:
Draw a ‘before’ picture with color what your area might look like.
Draw an ‘after’ picture with color what your area might look like.
Answer the seven questions on a separate sheet of paper.
DO NOT WRITE ON ‘OCEANOGRAPHY – THINK ABOUT IT!’ PAPER