Geology 155Geology 155OceanographyOceanography

Earth SystemEarth System

• System-System-A set or assemblage of things connected, A set or assemblage of things connected, associated, or interdependent, so as to form a associated, or interdependent, so as to form a complex unity;complex unity;. .

• Earth System-composed of interacting physical, Earth System-composed of interacting physical, chemical, and biological processes that move and chemical, and biological processes that move and change materials and energy on earth. The system change materials and energy on earth. The system provides the conditions necessary for life on the provides the conditions necessary for life on the planet. planet. – Example, plants, which are part of the living system, use Example, plants, which are part of the living system, use

solar energy to change carbon dioxide into organic carbon. solar energy to change carbon dioxide into organic carbon. Less carbon dioxide in the atmosphere helps cool the planet. Less carbon dioxide in the atmosphere helps cool the planet. Winds and ocean currents move heat from the tropics to Winds and ocean currents move heat from the tropics to higher latitudes, helping to warm the higher latitudes. higher latitudes, helping to warm the higher latitudes.

Photograph of earth taken on December 7, 1972 by the crew of Apollo 17 from a distance of about 45,000 km, while traveling to the moon. This image revolutionized our concept of earth, and it is one of the most famous photographs ever taken.Image from NASA Earth Observatory.

Right: Earth, the Blue Marble floating in the void-1997. earth as seen from space based on a montage of data from three

satellites. Image from NASA Earth Observatory.

FeedbacksFeedbacks

• Earth systems interact through Earth systems interact through feedbacks.feedbacks.– Positive feedbacks Positive feedbacks lead to instability. They lead to instability. They

speed up change in the system. speed up change in the system. – Negative feedbacks Negative feedbacks lead to stability. They lead to stability. They

reduce change in the system. reduce change in the system. – In past, systems all natural. Now humans In past, systems all natural. Now humans

have influence on planet, changing the have influence on planet, changing the operation of many systems. Because all operation of many systems. Because all systems are interconnected, a change in one systems are interconnected, a change in one systems influences all other systems. systems influences all other systems.

Earth Systems--Earth Systems--InteractionsInteractions

• The Carbon CycleThe Carbon Cycle

GoalGoal

• The goal of earth system science is to The goal of earth system science is to obtain a scientific understanding of the obtain a scientific understanding of the entire earth system on a global scale by entire earth system on a global scale by describing how its component parts and describing how its component parts and their interactions have evolved, how their interactions have evolved, how they function, and how they may be they function, and how they may be expected to continue to evolve on all expected to continue to evolve on all time scales.time scales.

Why Study OceansWhy Study Oceans

• The CO2 problem, global warming, and the ocean The CO2 problem, global warming, and the ocean and all inter-related. and all inter-related.

– The ocean influences climate including earth's surface The ocean influences climate including earth's surface temperature, by influencing: temperature, by influencing:

• The amount of CO2 in the atmosphere, The amount of CO2 in the atmosphere, • The transport of heat from the tropics to polar regions, The transport of heat from the tropics to polar regions, • The operation of the hydrological cycle, The operation of the hydrological cycle, • Earth's carbon cycles. Earth's carbon cycles.

– Most of the oxygen in the atmosphere comes from the Most of the oxygen in the atmosphere comes from the oceans. oceans.

– The oceans may be responsible for abrupt climate The oceans may be responsible for abrupt climate change. change.

– Will global warming plunge the world into the next ice Will global warming plunge the world into the next ice age? age?

Why Study Oceans?Why Study Oceans?

• Helps control our Helps control our climateclimate

Why Study Oceans?Why Study Oceans?• Fisheries and other resources of Fisheries and other resources of the ocean are important. the ocean are important. – Roughly 25% of the protein Roughly 25% of the protein

used by people comes from used by people comes from fish. fish.

– So much overfishing, fish are So much overfishing, fish are endangered endangered

• The loss of fish changes The loss of fish changes the marine food webs. the marine food webs.

• Changing food webs affect other Changing food webs affect other life and processes in the sea. life and processes in the sea. – How many fish can be How many fish can be

caught?caught?

•from a 1920 postcard. (Census of Marine Life)from a 1920 postcard. (Census of Marine Life)

http://marinebio.org/i/fishmarket.jpg

Sea Salt - Maio Island -

Why Study Oceans?Why Study Oceans?

• El Niño results from in part from El Niño results from in part from changes in oceans. changes in oceans. – Oceans influence weather patterns. Oceans influence weather patterns. – A change of temperature of surface A change of temperature of surface

water in the western north Pacific and in water in the western north Pacific and in the tropical Atlantic can cause drought the tropical Atlantic can cause drought in Texas, and flooding and mudslides in in Texas, and flooding and mudslides in California. California.

Why Should We Care About Why Should We Care About Oceanography?Oceanography?

• Petroleum and Petroleum and mineral resourcesmineral resources

CA gov.

Underwater mineral deposit Extracting the oil

Why Should We Care About Why Should We Care About Oceanography?Oceanography?

• RecreationRecreation

LA CO Fire

Why Study Oceans? Why Study Oceans? • Damaging ocean damages us.Damaging ocean damages us.

• Coastal pollutionCoastal pollution– Coastal pollution seems to be the cause of large scale harmful algal Coastal pollution seems to be the cause of large scale harmful algal

blooms. blooms. – Coastal pollution seems to be the cause of large scale harmful algal Coastal pollution seems to be the cause of large scale harmful algal

blooms. blooms. – Pollution also seems to create dead zones in some regions. Pollution also seems to create dead zones in some regions. – What causes the dead zones off Mississippi and Oregon in the What causes the dead zones off Mississippi and Oregon in the

summer?summer?

Oiled Jackass penguins, South Africa.© International Fund for Anial Welfare (IFAW).

Why Study OceansWhy Study Oceans

• Coastal processes influence beaches and Coastal processes influence beaches and those who live and work near the beach. those who live and work near the beach.

• Ocean waves erode beaches. Ocean waves erode beaches. • Structures along beach in most areas Structures along beach in most areas

will be destroyed in the long run. will be destroyed in the long run. • Cost of protecting structures along the Cost of protecting structures along the

beaches is very high. beaches is very high. • Why do some beaches lose so much Why do some beaches lose so much

sand that houses are destroyed? sand that houses are destroyed?

What is Oceanography?What is Oceanography?

OceanographyOceanographySubdisciplinesSubdisciplines

• GeologicalGeological

• PhysicalPhysical

• ChemicalChemical

• BiologicalBiological

How Do the Oceans Impact How Do the Oceans Impact Us?Us?

• HurricanesHurricanes– KatrinaKatrina– IreneIrene

•TsunamiTsunami•Indonesia 2004Indonesia 2004•JapanJapan

Hurricane KatrinaHurricane Katrina

Hurricane KatrinaHurricane Katrina

2004 Indonesia Tsunami2004 Indonesia Tsunami

Click image above to view film footage

Indonesia TsunamiIndonesia Tsunami

Japan Tsunami-2011Japan Tsunami-2011

simmania.darkbb.com New York Times

Gaining Knowledge of the Gaining Knowledge of the OceansOceans

• Early VoyagesEarly Voyages

• Age of DiscoveryAge of Discovery

• Science for VoyagingScience for Voyaging

Early VoyagesEarly Voyages

Early Voyages Early Voyages

• Polynesia ColonizationPolynesia Colonization

• VikingsVikings

• ChineseChinese

The Age of DiscoveryThe Age of Discovery

• Prince Henry the NavigatorPrince Henry the Navigator

• Christopher ColumbusChristopher Columbus

• Ferdinand MagellanFerdinand Magellan

Voyaging for ScienceVoyaging for Science• The First Scientific ExplorationThe First Scientific Exploration

• James CookJames Cook• Charles DarwinCharles Darwin

• The Challenger ExpeditionThe Challenger Expedition

The Challenger ExpeditionThe Challenger Expedition• Major Contributions . . .Major Contributions . . .

– First pure scientific expeditionFirst pure scientific expedition– Life was possible below 549 m (1800 ft)Life was possible below 549 m (1800 ft)– Discovered 4,717 new speciesDiscovered 4,717 new species– Collected ocean water informationCollected ocean water information

• Temperature, salinity, and water densityTemperature, salinity, and water density

• Ocean current and sediment distributionOcean current and sediment distribution

2121stst Century Technology Century Technology

UnderwaterUnderwater• SonarSonar

• SubmersiblesSubmersibles

SatelliteSatellite• MODISMODIS• QuikSCATQuikSCAT

• TRMMTRMM

Ocean FactsOcean Facts• About 70% of Earth’s surface is covered by water.About 70% of Earth’s surface is covered by water.• Average depth of the Pacific Ocean = 4,638 mAverage depth of the Pacific Ocean = 4,638 m• Average depth of the Atlantic Ocean = 3,872 mAverage depth of the Atlantic Ocean = 3,872 m• Average temperature = 3.9°C (39.0°F)Average temperature = 3.9°C (39.0°F)• Age of oceans = 4 billion yearsAge of oceans = 4 billion years

Hydrologic CycleHydrologic Cycle

• Continuous cycle of how water moves through different reservoirs, or from ocean to air, onto land, to lakes and streams and groundwater back to the sky and ocean.

Hypsographic CurveHypsographic Curve

• Shows Shows distribution of distribution of elevations and elevations and depths on Earthdepths on Earth

( Know how to read graph)