Oceanography I Introduction to Oceans A Oceanography the

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Oceanography

Oceanography

I. Introduction to Oceans A. Oceanography – the study and exploration of the world’s

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

II. Properties of Ocean Water A. Composition of Ocean Water 1. H 2 O

II. Properties of Ocean Water A. Composition of Ocean Water 1. H 2 O is 96. 5 % 2. other elements is 3. 5% 3. salinity – dissolved salt content of a body of water

II. Properties of Ocean Water B. Temperature of Ocean Water 1. as temperature increases,

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

II. Properties of Ocean Water C. Pressure – pressure increases as the ocean depths

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

III. Oceans – a continuous body of saltwater that covers approximately 70% of the

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

III. Oceans C. INDIAN - deeper than the Atlantic, shallower than the Pacific D.

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

IV. Life in the Ocean A. Plankton – drifting organisms in aquatic environments (marine

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

IV. Life in the Ocean B. Nekton – organisms that swim in the ocean

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

IV. Life in the Ocean C. Benthos – community of organisms that live on,

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

Threats to the Ocean The oceans are huge but are becoming increasingly more polluted.

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

V. Marine Ecosystems Includes: estuaries, coral reefs, oceans, and polar ecosystems ¡ Marine ecosystems

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

Estuaries

Estuaries

Estuaries ¡ ¡ ¡ fresh _____ water from rivers An ecosystem where _____ salt

Estuaries ¡ ¡ ¡ fresh _____ water from rivers An ecosystem where _____ salt water 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 salinity because able to tolerate variations in ____ salt content of the water varies as the _____ fresh and salt water mix.

Threats to Estuaries provide harbors, access to the ocean, and connections to rivers. As

Threats to 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. ¡

Coral Reefs

Coral Reefs

Coral Reef ¡ ¡ ¡ limestone Coral reefs are _____ islands in the sea

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 diverse ecosystems on Earth. most ____ warm salt water Corals can only live in _____ light for where there is enough ______ photosynthesis. Therefore, coral reefs are only found in shallow, tropical seas.

Threats to Coral Reefs ¡ ¡ ¡ If the water surrounding a reef is

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.

Polar Ecosystem

Polar Ecosystem

Polar Ecosystems The ice-covered polar caps can be considered marine ecosystems because nearly all

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

Threats to Polar Ecosystems Oil extraction, tourism, and garbage are the worst threats to

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. ¡

Upwelling refers to deep water that is brought to the surface. Areas of upwelling

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.

To understand upwelling, you must be familiar with how the Coriolis Effect affects ocean

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. http: //www. classzone. com/books/earth_science/terc/content/visualizations/es 19 04/es 1904 page 01. cfm

The deep water that surfaces in upwelling is cold; by looking at Sea Surface

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.

Upwelled water also contains nutrients (nitrate, phosphate, silicate) and dissolved gases (oxygen and carbon

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.

Phytoplankton photosynthesize using specialized color pigments called chlorophyll. Thus, “Ocean Color” maps are another

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?

Ecological and Economic effects of upwelling: Upwelling leads to more phytoplankton ¡ More phytoplankton

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 ¡

Even though upwelling areas account for only 1% of the ocean surface, they support

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

Phytoplankton come in many shapes and forms. Collectively they form the base of oceanic

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.

Some climatic events can reduce upwellings. ~ El Nino

Some climatic events can reduce upwellings. ~ El Nino

Along Peru’s coast, an El Nino event decreases the coastal winds. Thus the upwelling

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.

What is La Niña? ¡ La Niña is characterized by unusually cold ocean temperatures

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.

VI. Instruments of Investigation A. B. SCUBA – Self-Contained Underwater Breathing Apparatus. Tanks of

VI. Instruments of Investigation A. B. 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

Instruments of Investigation (cont. ) C. Geostationary operational Environmental Satellites (GOES) orbit the Earth

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

Instruments of Investigation (cont. ) D. Underwater Laboratories – The Aquarius Underwater Laboratory is

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

Instruments of Investigation (cont. ) E. Deep ocean submersibles – Over the last few

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.

VIII. Waves and Wave Action A. Causes – wind and earthquakes B. Characteristics of

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

VIII. Waves and Wave Action 4. wave frequency – the number of waves that

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

VIII. Waves and Wave Action 6. wave height – vertical distance between crest and

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

VIII. Waves and Wave Action 10. swells – formation of long wavelength surface waves

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

VIII. Waves and Wave Action C. Tsunami – a great sea wave caused especially

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

VIII. Waves and Wave Action D. storm surge – an offshore rise of water

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

IX. Tides A. Tidal range – the vertical difference between high and low tides

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

IX. Tides B. Spring Tide – exceptionally high and low tides that occur at

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

X. Currents and Climates A. Surface currents – Horizontal movement of seawater in the

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

At the shoreline ¡ Water becomes shallow, wave height increases because wave length decreases

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

Wave refraction ¡ ¡ Close to coast, water gets more shallow Waves are slowed

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

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

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

A sequence of features is produced as headlands are degraded ¡ Sea cliffs ¡

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

 • Headlands may be eroded back leaving a remnant (stack)

• Headlands may be eroded back leaving a remnant (stack)

Longshore drift ¡ Waves arrive at a coast at an angle (swash) ¡ Backwash

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

Coastal deposition ¡ 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

spit = curved extension ¡ May grow across a bay (baymouth bar) ¡ May

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

Types of Coastline Submergence and emergence changes coastlines Pocket beaches

Types of Coastline Submergence and emergence changes coastlines Pocket beaches

Emergent coast ¡ Uplifted land surface ¡ Coastal landforms are found above present sea

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

Barrier Island Coasts ¡ ¡ ¡ Occur on low lying coasts with gentle gradients

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

Oceanography – Think about it! You will be given a scenario which you will

Oceanography – Think about it! You will be given a scenario which you will read. You will then: 1. Draw a ‘before’ picture with color what your area might look like. 2. Draw an ‘after’ picture with color what your area might look like. 3. Answer the seven questions on a separate sheet of paper. DO NOT WRITE ON ‘OCEANOGRAPHY – THINK ABOUT IT!’ PAPER