Essentials of Oceanography

Alan P. Trujillo Al Trujillo teaches at Palomar Community College in San Marcos, CA, where he is co-Director of the Oceanography Program and Chair of the Earth Sciences Department.  He received his bachelor’s degree in geology from the University of California at Davis and his master’s degree in geology from Northern Arizona University, afterwards working for several years in industry as a development geologist, hydrogeologist, and computer specialist.  Al began teaching in the Earth Sciences Department at Palomar in 1990 and in 1997 was awarded Palomar’s Distinguished Faculty Award for Excellence in Teaching.  He has co-authored Introductory Oceanography with Hal Thurman and is a contributing author for the textbooks Earth and Earth Science.  In addition to writing and teaching, Al works as a naturalist and lecturer aboard natural history expedition vessels in Alaska and the Sea of Cortez/Baja California.  His research interests include beach processes, sea cliff erosion, and computer applications in oceanography.  Al and his wife, Sandy, have two children, Karl and Eva.   Harold V. Thurman Hal Thurman retired in May 1994, after 24 years of teaching in the Earth Sciences Department of Mt. San Antonio College in Walnut, California.  Interest in geology led to a bachelor’s degree from Oklahoma A&M University, followed by seven years working as a petroleum geologist, mainly in the Gulf of Mexico, where his interest in oceans developed.  He earned a master’s degree from California State University at Los Angeles and then joined the Earth sciences faculty at Mt. San Antonio College.  Other books that Hal has co-authored include Introductory Oceanography (with Alan Trujillo) and a marine biology textbook.  He has also written articles on the Pacific, Atlantic, Indian, and Arctic Oceans for the 1994 edition of World Book Encyclopedia and served as a consultant on the National Geographic publication Realms of the Sea.  He still enjoys going to sea on vacations with his wife Iantha.

Introduction I.1 What Is Oceanography?

I.2 How Are Earth’s Oceans Unique?

I.3 What Is Rational Use of Technology?

 

Chapter 1 — Introduction to Planet "Earth" 1.1 How Many Oceans Exist On Earth?

    The Four Principal Oceans, Plus One

    The Seven Seas?

    Comparing the Oceans to the Continents

1.2 How Was Early Exploration of the Oceans Achieved?

    Early History

    The Middle Ages

    The Age of Discovery in Europe

    The Beginning of Voyaging for Science

    History of Oceanography…To Be Continued

1.3 What Is the Nature of Scientific Inquiry?

    Observations

    Hypothesis

    Testing

    Theory

    Theories and the Truth

1.4 How Were Earth and the Solar System Created?

    The Nebular Hypothesis

    Protoearth

    Density and Density Stratification

    Earth’s Internal Structure

1.5 How Were Earth’s Atmosphere and Oceans Created?

     Origin of Earth’s Atmosphere

     Origin of Earth’s Oceans

1.6 Did Life Begin in the Oceans?

    The Importance of Oxygen to Life

    Stanley Miller’s Experiment

    Evolution and Natural Selection

    Plants and Animals Evolve

1.7 How Old Is Earth?

     Radiometric Age Dating

     The Geologic Time Scale

 

Chapter 2 — Plate Tectonics and the Ocean Floor

2.1 What Evidence Supports Continental Drift?

    Fit of the Continents

    Matching Sequences of Rocks and Mountain Chains

    Glacial Ages and Other Climate Evidence

    Distribution of Organisms

    Objections to the Continental Drift Model

2.2 What Evidence Supports Plate Tectonics?

    Earth’s Magnetic Field and Paleomagnetism

    Sea Floor Spreading and Features of the Ocean Basins     Other Evidence from the Ocean Basins

    The Acceptance of a Theory

2.3 What Features Occur at Plate Boundaries?

    Divergent Boundary Features

    Convergent Boundary Features

    Transform Boundary Features

2.4 Testing the Model: What Are Some Applications of Plate Tectonics?

    Hotspots and Mantle Plumes

    Seamounts and Tablemounts

    Coral Reef Development

    Detecting Plate Motion with Satellites

2.5 How Has Earth Changed in the Past…And How Will it Look in the Future?

    The Past: Paleogeography

    The Future: Some Bold Predictions

2.6 Plate Tectonics…To Be Continued

 

Chapter 3 — Marine Provinces

3.1 What Techniques Are Used to Determine Ocean Bathymetry?

    Soundings

    Echo Soundings

    Seismic Reflection Profiles

3.2 What Does Earth’s Hypsographic Curve Reveal?

3.3 What Features Exist on Continental Margins?

    Passive versus Active Continental Margins

    Continental Shelf

    Continental Slope

    Submarine Canyons and Turbidity Currents

3.4 What Features Exist in the Deep-Ocean Basins?

    Abyssal Plains

    Volcanic Peaks of the Abyssal Plains

    Ocean Trenches and Volcanic Arcs

3.5 What Features Exist along the Mid-Ocean Ridge?

    Volcanic Features

    Hydrothermal Vents

    Fracture Zones and Transform Faults

 

Chapter 4 — Marine Sediments

 

4.1 What Is Lithogenous Sediment?

    Origin

    Composition

    Sediment Texture

    Distribution

4.2 What Is Biogenous Sediment?

    Origin

    Composition

    Distribution

4.3 What Is Hydrogenous Sediment?

    Origin

    Composition and Distribution

4.4 What Is Cosmogenous Sediment? Origin, Composition, and Distribution

4.5 What Mixtures of Sediment Exist?

4.6 A Summary: How Are Pelagic and Neritic Deposits Distributed?

     Neritic Deposits

     Pelagic Deposits

     How Sea Floor Sediments Represent Surface Conditions

     Worldwide Thickness of Marine Sediments

4.7 What Events Are Revealed by Sea Floor Sediments?

4.8 What Resources Do Ocean Sediments Provide?

    Energy Resources

    Other Resources

 

Chapter 5 — Water and Seawater

5.1 Why Does Water Have Such Unusual Chemical Properties?

    Atomic Structure

    The Water Molecule

5.2 What Other Important Properties Does Water Possess?

    Water’s Thermal Properties

    Water Density

5.3 How Salty Is Seawater?

    Salinity

    Determining Salinity

    Comparing Pure Water and Seawater

5.4 Why Does Seawater Salinity Vary?

    Salinity Variations

    Processes Affecting Seawater Salinity     Dissolved Components Added and Removed from Seawater

5.5 Is Seawater Acidic or Basic?

    The pH Scale

    The Carbonate Buffering System

    Recent Increase in Ocean Acidity

5.6 How Does Seawater Salinity Vary at the Surface and with Depth?

    Surface Salinity Variation

    Salinity Variation with Depth

    Halocline

5.7 How Does Seawater Density Vary with Depth?

    Factors Affecting Seawater Density

    Density Variation with Depth

    Pycnocline and Thermocline

5.8 What Methods Are Used to Desalinate Seawater?

     Distillation

     Membrane Processes

     Other Methods of Desalination

 

Chapter 6 — Air-Sea Interaction

6.1 What Causes Earth’s Seasons?

6.2 How Does Uneven Solar Heating Affect Earth?

    Distribution of Solar Energy

    Oceanic Heat Flow

6.3 What Physical Properties Does the Atmosphere Possess?

     Composition

     Temperature

     Density

     Water Vapor Content

     Pressure

     Movement

     An Example: A Nonspinning Earth

6.4 How Does the Coriolis Effect Influence Moving Objects?

    Example 1: Perspectives and Frames of Reference on a Merry-Go-Round

    Example 2: A Tale of Two Missiles

    Changes in the Coriolis Effect with Latitude

6.5 What Global Atmospheric Circulation Patterns Exist?

    Circulation Cells

    Pressure

    Wind Belts

    Boundaries

    Circulation Cells: Idealized or Real?

6.6 What Weather and Climate Patterns Does the Ocean Exhibit?

     Weather versus Climate

    Winds

    Storms and Fronts

    Tropical Cyclones (Hurricanes)

    The Ocean’s Climate Patterns

6.7 How Do Sea Ice and Icebergs Form?

     Formation of Sea Ice

     Formation of Icebergs

6.8 What Causes the Atmosphere’s Greenhouse Effect?

    Earth’s Heat Budget and Changes in Wavelength

    Which Gases Contribute to the Greenhouse Effect?

    What Changes Will Occur as a Result of Increased Global Warming?

    What Should Be Done To Reduce Greenhouse Gases?

6.9 Can Power from Wind Be Harnessed as a Source of Energy?

 

Chapter 7 — Ocean Circulation

7.1 How Are Ocean Currents Measured?

     Surface Current Measurement

     Deep Current Measurement

7.2 How Are Ocean Surface Currents Organized?

    Origin of Surface Currents

    Main Components of Ocean Surface Circulation

    Other Factors Affecting Ocean Surface Circulation

    Ocean Currents and Climate

7.3 What Causes Upwelling and Downwelling?

    Diverging Surface Water

    Converging Surface Water

    Coastal Upwelling and Downwelling

    Other Causes of Upwelling

7.4 What Are the Main Surface Circulation Patterns in Each Ocean?

    Antarctic Circulation

    Atlantic Ocean Circulation

    Indian Ocean Circulation

    Pacific Ocean Circulation

7.5 What Deep-Ocean Currents Exist?

    Origin of Thermohaline Circulation

    Sources of Deep Water

    Worldwide Deep-Water Circulation

7.6 Can Power from Currents Be Harnessed as a Source of Energy?

 

Chapter 8 — Waves and Water Dynamics

8.1 What Causes Waves?

8.2 How Do Waves Move?

8.3 What Characteristics Do Waves Possess?

    Wave Terminology

    Circular Orbital Motion

    Deep-Water Waves

    Shallow-Water Waves

    Transitional Waves

8.4 How Do Wind-Generated Waves Develop?

    Wave Development

    Interference Patterns

8.5 How Do Waves Change in the Surf Zone?

    Physical Changes as Waves Approach Shore

    Breakers and Surfing

    Wave Refraction

    Wave Reflection

8.6 How Are Tsunami Created?

    Coastal Effects

    Some Examples of Historic and Recent Tsunami

    Tsunami Warning System

8.7 Can Power from Waves Be Harnessed as a Source of Energy?

     LIMPET 500: An Example of a Wave Power Plant

     Global Coastal Wave Energy Resources

 

Chapter 9 — Tides

9.1 What Causes the Tides?

    Tide-Generating Forces

    Tidal Bulges: The Moon's Effect

    Tidal Bulges: The Sun's Effect

    Earth’s Rotation and the Tides

9.2 How Do Tides Vary During a Monthly Tidal Cycle?

    The Monthly Tidal Cycle

    Complicating Factors

    Idealized Tide Prediction

9.3 What Do Tides Really Look Like in the Ocean?

     Amphidromic Points and Cotidal Lines

     Effect of the Continents

     Other Considerations

9.4 What Types of Tidal Patterns Exist?

     Diurnal Tidal Pattern

     Semidiurnal Tidal Pattern

     Mixed Tidal Pattern

9.5 What Tidal Phenomena Occur in Coastal Regions?

    An Example of Tidal Extremes: The Bay of Fundy

    Coastal Tidal Currents

    Whirlpools: Fact or Fiction?

9.6 Can Tidal Power Be Harnessed as a Source of Energy?

     Tidal Power Plants

 

Chapter 10 — The Coast: Beaches and Shoreline Processes

10.1 How Are Coastal Regions Defined?

    Beach Terminology

    Beach Composition

10.2 How Does Sand Move on the Beach?

     Movement Perpendicular to Shoreline

     Movement Parallel to Shoreline

10.3 What Features Exist along Erosional and Depositional Shores?

    Features of Erosional Shores

    Features of Depositional Shores

10.4 How Do Changes in Sea Level Produce Emerging and Submerging Shorelines?

    Features of Emerging Shorelines

    Features of Submerging Shorelines

    Changes in Sea Level

10.5 What Characteristics Do U.S. Coasts Exhibit?

    The Atlantic Coast

    The Gulf Coast

    The Pacific Coast

10.6 What Is Hard Stabilization?

     Groins and Groin Fields

     Jetties

     Breakwaters

     Seawalls

10.7 What Alternatives to Hard Stabilization Exist?

     Construction Restrictions

     Beach Replenishment

     Relocation

 

Chapter 11 — The Coastal Ocean

11.1 What Laws Govern Ocean Ownership?

     Mare Liberum and the Territorial Sea

     Law of the Sea

11.2 What Characteristics Do Coastal Waters Exhibit?

    Salinity

    Temperature

    Coastal Geostrophic Currents

11.3 What Types of Coastal Waters Exist?

     Estuaries

     Coastal Wetlands

     Lagoons

     Marginal Seas

11.4 What Is Pollution?

    Marine Pollution: A Definition

    Standard Laboratory Bioassay

    The Issue of Waste Disposal in the Ocean

11.5 What Are the Main Types of Marine Pollution?

    Petroleum

    Sewage Sludge

    DDT and PCBs

    Mercury and Minamata Disease

    Non-Point-Source Pollution and Trash

 

 

Chapter 12 —Marine Life and the Marine Environment

12.1 What Are Living Things and How Are They Classified?

     A Working Definition of Life

     The Three Domains of Life

     The Five Kingdoms of Organisms

     Taxonomic Classification

12.2 How Are Marine Organisms Classified?

    Plankton (Floaters)

    Nekton (Swimmers)

    Benthos (Bottom Dwellers)

12.3 How Many Marine Species Exist?

     Why Are There So Few Marine Species?

     Species in Pelagic and Benthic Environments

12.4 How Are Marine Organisms Adapted for the Physical Conditions of the Ocean?

    Need for Physical Support

    Water’s Viscosity

    Temperature

    Salinity

    Dissolved Gases

    Water’s High Transparency

    Pressure

12.5 What Are the Main Divisions of the Marine Environment?

    Pelagic (Open Sea) Environment

    Benthic (Sea Bottom) Environment

   

 

Chapter 13 — Biological Productivity and Energy Transfer

13.1 What Is Primary Productivity?

    Measurement of Primary Productivity

    Factors Affecting Primary Productivity

    Light Transmission in Ocean Water

    Why Are the Margins of the Oceans So Rich in Life?

13.2 What Kinds of Photosynthetic Marine Organisms Exist?

    Seed-Bearing Plants (Anthophyta)

    Macroscopic (Large) Algae

    Microscopic (Small) Algae

    Photosynthetic Bacteria

13.3 How Does Regional Primary Productivity Vary?

    Productivity in Polar Oceans

    Productivity in Tropical Oceans

    Productivity in Temperate Oceans

    Comparing Regional Productivity

13.4 How Are Energy and Nutrients Passed Along in Marine Ecosystems?

     Flow of Energy in Marine Ecosystems

     Flow of Nutrients in Marine Ecosystems

13.5 What Oceanic Feeding Relationships Exist?

     Feeding Strategies

     Trophic Levels

     Transfer Efficiency

     Food Chains, Food Webs, and the Biomass Pyramid

     Symbiosis

13.6 What Issues Affect Marine Fisheries?

    Marine Ecosystems and Fisheries

    Overfishing

    Incidental Catch

    Fisheries Management

    Seafood Choices

 

Chapter 14 — Animals of the Pelagic Environment

14.1 How Are Marine Organisms Able to Stay above the Ocean Floor?

    Use of Gas Containers

    Ability to Float

    Ability to Swim

    The Diversity of Planktonic Animals

14.2 What Adaptations Do Pelagic Organisms Possess for Seeking Prey?

    Mobility: Lungers versus Cruisers

    Swimming Speed

    Cold-Blooded versus Warm-Blooded Organisms

    Adaptations of Deep-Water Nekton

14.3 What Adaptations Do Pelagic Organisms Possess to Avoid Being Prey?

    Schooling

    Other Adaptations

14.4 What Characteristics Do Marine Mammals Possess?

    Mammalian Characteristics

    Order Carnivora

    Order Sirenia

    Order Cetacea

14.5 An Example of Migration: Why Do Gray Whales Migrate?

     Migration Route

     Reasons for Migration

     Timing of Migration

     Gray Whales as Endangered Species

 

Chapter 15 — Animals of the Benthic Environment

15.1 How Are Benthic Organisms Distributed?

15.2 What Communities Exist along Rocky Shores?

    Intertidal Zonation

    The Spray (Supratidal) Zone: Organisms and Their Adaptations

    The High Tide Zone: Organisms and Their Adaptations

    The Middle Tide Zone: Organisms and Their Adaptations

    The Low Tide Zone: Organisms and Their Adaptations

15.3 What Communities Exist along Sediment-Covered Shores?

    Physical Environment of the Sediment

    Intertidal Zonation

    Sandy Beaches: Organisms and Their Adaptations

    Mud Flats: Organisms and Their Adaptations

15.4 What Communities Exist on the Shallow Offshore Ocean Floor?

    Rocky Bottoms (Subtidal): Organisms and Their Adaptations

    Coral Reefs: Organisms and Their Adaptations

15.5 What Communities Exist on the Deep-Ocean Floor?

    The Physical Environment

    Food Sources and Species Diversity

    Deep-Sea Hydrothermal Vent Biocommunities: Organisms and Their Adaptations

    Low-Temperature Seep Biocommunities: Organisms and Their Adaptations

    The Deep Biosphere

 

Afterword

A.1 What Are Marine Protected Areas?

A.2 What Can I Do?

 

Appendixes

I    Metric and English Units Compared

II   Geographic Locations

III  Latitude and Longitude on Earth

IV   A Chemical Background: Why Water Has 2 H’s and 1 O

V    Careers in Oceanography

 

Glossary

 

Credits and Acknowledgements

 

Index