Intro to Oceanography Study of the ocean, its surroundings, and life within it. How does it differ from Marine Biology? Marine bio studies marine organisms’ anatomy, physiology, behavior; more individualistic. Covers 71% of the Earth’s surface The five principal oceans 1. Pacific 2. Atlantic 3. Indian 4. Arctic 5. Southern or Antarctic Ocean Artic Atlantic Pacific Indian Southern or Antarctic Comparison of Oceans Size Ocean Area (square miles) Average Depth (ft) D Pacific Ocean 64,186,000 15,215 Marian Atlantic Ocean 33,420,000 12,881 Puerto R Indian Ocean 28,350,000 13,002 Java Southern Ocean 7,848,300 sq. miles (20.327 million sq km ) 13,100 - 16,400 ft deep (4,000 to 5,000 meters) Arctic Ocean 5,106,000 3,953 the souther Trench, Euras 7 SEAS: smaller and shallower and somewhat enclosed by land North Pacific, South Pacific, North Atlantic, South Atlantic, Indian, Arctic, Southern or Antarctic The Seven Seas? The major branches of oceanography : a) Physical oceanography, b) Chemical oceanography, c) Geological oceanography, and d) Biological oceanography. • Physical oceanography • Chemical oceanography It is the study of physical conditions that are prevailing in the seas and oceans. it deals with all large scale physical processes and their effects that are happening within the oceans : waves, currents, tides, Chemical Oceanography attempts to analyses: the interactions between oceans, lithosphere, atmosphere and biosphere, sea water chemistry, controls in chemical distribution, components of marine sediments and chemical controls in biological production • Geological oceanography The study of basic concepts of lithosphere & hydrosphere : the oceanic crust, continental margins, ocean bottom relief, ocean basins, oceanic ridges, riftvalleys, Island arcs, sea water, marine sedimentation, geology of corals • Biological Oceanography The study of marine life, habitat, interactions, abiotic environment, phytoplankton and primary production, zooplankton, migrations and changes, energy flow & mineral cycling, marine food chains, food webs, nektons, marine reptiles, mammals, seabirds, mariculture, Benthic plants and animals, intertidal environments, beaches, coral reefs, estuaries and mangroves are all studied under biological oceanography. 20th Century Voyages Contributed to Oceanographic Knowledge (right) Echo sounders sense the contour of the seafloor by beaming sound waves to the bottom and measuring the time required for the sound waves to bounce back to the ship. If the round-trip travel time and wave velocity are known, distance to the bottom can be calculated. This technique was first used on a large scale by the German research vessel Meteor in the 1920s. It formally began in the 1800’s. Previously, it was thought that the deep ocean had no life below 550 m (Edward Forbes- Azoic Theory). Oceanography history → to understand why and how people apply marine sciences today Latitude measured by using a sextant by measuring position of sun and stars. John Harrison of England is credited with solving the longitude problem by inventing an accurate timepiece Compass came from China 4th century BC, used in Europe 1190 AD GPS- global positioning system- uses satellite tracking Prior to then: 1500 B.C., Phoenicians were skilled sailors and traded goods Migration Routes of Polynesia An early stick chart from Micronesia shows the waves and currents around the islands which are represented by shells. Voyage of Columbus (1492) and Magellan (1519) Cook (1700’s)- sailed twice around the world 1st European to visit Hawaii Cook Humboldt (1800’s)- German naturalist, contributions in geophysics, meteorology, and oceanography The Humboldt Current, also called the Peru Current, is a cold, lowsalinity ocean current that flows north along the western coast of South America.[1] It is an eastern boundary current flowing in the direction of the equator, and extends 500–1,000 km (310–620 mi) offshore. Voyage of the HMS Beagle Darwin (1831): •Subsidence theory of coral reef formation (atolls) & origin of species Voyage of the HMS Challenger (1872-1876) • collected thousands of biological and sea bottom samples • traveled in every ocean except arctic cruise directed by Charles Wyville Thompson • 362 stations, 715 new genera, 5000 new species • discovered Mariana Trench and Mindarnia (34,000 ft deep) Recent: Meteor Expedition (1925)- introduced modern optical and electronic equipment (echo sounder) Glomar Challenger (1968)- drilling for deep sea sediments Rachel Louise Carson (1907-1964) Marine biologist at U.S. Bureau of Fisheries & Fish & Wildlife Service Jacque Cousteau (1910-1997) Navy officer, explorer, film maker, inventor of scuba (1947) "From birth, man carries the weight of gravity on his shoulders. He is bolted to the earth. But man has only to sink beneath the surface and he is free.” Bob Ballard (1942-) Navy officer, explorer, film maker
