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Physical Oceanography. Chapter 20.1. Branches of Oceanography. Physical Oceanography - study of the motions of seawater, particularly waves currents and tidal motion.
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Physical Oceanography Chapter 20.1
Branches of Oceanography • Physical Oceanography - study of the motions of seawater, particularly waves currents and tidal motion. • Chemical Oceanography - chemistry of seawater and reactions between the atmosphere and hydrosphere. More recently looks at how changes in seawater temperature (El Nino) and salinity affect global climate.
Biological Oceanography - study of life in the oceans, includes marine biology and ecology. • Geological Oceanography - study of the shape and geologic features of the ocean floor.
Major Oceans • The three major oceans are : 1._______-largest, deepest, coldest, least salty. 2.__________- second largest, shallow, warm, salty. 3. _________- intermediate in depth, temperature, and salinity. • The _______Ocean near the north pole, and the ____________ Ocean near the south pole contain vast expanses of sea ice. Pacific Atlantic Indian Arctic Antarctic
Methods of Studying the Ocean The Topex/Poseidon _____________ orbits 1331 km above the Earth, gathering information about the oceans. satellite Sonar _____________ maps ocean floor topography by timing how long it takes sound waves to bounce off the ocean floor. submersibles Underwater vessels called _________________ investigate the deepest ocean trenches.
Sonar (also called echo-sounding) • Sound waves travel how fast in seawater? • How deep is the water if it takes ten seconds for the sound wave to go from ship to ocean floor and back to ship? 1,454 m/s 7,270 m Calculation: (10 s times 1,454 m/s divided by 2 )
Submersibles • Underwater research vessels, called submersibles, also enable oceanographers to study the ocean depths. • They can perform tasks ranging from photography to collecting samples.
Several types of submersibles have been used for underwater research. • One early type is the bathysphere, a spherical diving vessel that was first used for deep-ocean exploration. • This vessel carries scientists and is lowered down by cables.
Another type of submersible is called a bathyscaph. • This is a self propelled, free moving submarine. • Alvin is a well known example. • Hold 1 pilot and 2 scientists.
Robot submersibles enable the ocean to be study at depths that are unsafe for humans. • Jason Jr, a highly maneuverable robot toured the inside of the titanic. • They can tour undersea volcanoes and canyons.
submersible • The picture below is of a _____________.