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Oceanographers study the fundamental properties of ocean water including:
Temperature
Isotherms (lines of equal temperature) generally trend east-west.
Changes seasonally.
Permanent feature in tropical and temperate oceans.
Seasonal thermoclines develop at temperate latitudes.
Non-existent near the poles.
Evaporation
Precipitation
Ice formation and melting
Run-off
Salinity varies with latitude, depth.
Controls the physical structure of the oceans.
The pycnocline (transition layer) is a
zone of rapid change in density.
It separates the surface mixed layer from the deep layer.
Light transmission
Most light is absorbed within the top 1 meter of the ocean; this contributes to the warming of the surface layer.
Light changes with depth.
Photic and aphotic zones
The velocity in water is 1,445 m/sec compared to 334 m/sec in air.
Affected by temperature, salinity, pressure
SOFAR channel: channel in which sound is focused
The sun provides the energy to run the cycle.
The processes of evaporation and precipitation provide the links.
Water from the land is returned via run-off.
Waters high heat capacity plays a fundamental role in determining weather patterns and climate.
The relative proportions of the major constituents in seawater are constant.
The salinity of the oceans has not changed for 1.5 billion years; input and output rates of salt are balanced.
The density of seawater plays an important role in physical structuring of the oceans.
Gases in seawater are determined by diffusion and biological processes.
The hydrologic cycle describes the exchange of water among the various reservoirs on Earth.
The biogeochemical cycle describes the cycling of organic matter and inorganic nutrients among the Earth's reservoirs.
http://dusk.geo.orst.edu/oceans/chem_phys2.html
Salinity
Density
Temperature
Related to latitude and insolation.
Sea Surface Temperatures
in August
Figure
Sea Surface Temperatures
in February
Figure
Thermocline
Zone of rapid change in temperature that separates warm low density water from cold high density water.
Thermoclines:
Polar, Temperature, Tropical
Figure
Latitudinal Variation in
Temperature vs. Depth
Figure
Growth & Decay of the Seasonal Thermocline
Figure
Salinity
Salinity patterns are caused by processes that add or remove water molecules.
Sea Surface Salinity
in August
Figure
Influence of Evaporation and
Precipitation on Salinity
Figure
Halocline Figure
Salinity varies with depth. Haloclines are zones of rapid change in salinity.
Salinity Distribution in the
Western Atlantic
Figure
Density
The density structure of the ocean
Depends on temperature, salinity, and pressure.
Density Structure of the
Oceans
Figure
Light and Sound
The chemical and physical structure of the oceans affects
Sound transmission
Light Transmission
Light transmission affects life both directly and indirectly.
Light
Absorption in the Open Ocean
Figure
Light Absorption in Nearshore Waters
Figure
Sound
Sound is transmitted more effectively in water than in air.
Velocity of Sound
Figure
SOFAR Channel
where sound is focused
(Sound Fixing And Ranging)
Figure
Gases in Seawater:
Sources & Sinks
Figure
Oxygen advection
in the Atlantic Ocean
Figure 5-17(b)
Helium-3 Used to Trace Water Movement
Figure 5-16
The Hydrologic Cycle
Exchange of water between the ocean, land, and atmosphere.
The Hydrologic Cycle
Figure 5-20
The Biogeochemical Cycle
Figure
Summary
Waters unique properties are mostly due to its asymmetric shape and hydrogen bonds.MORE on OCEAN ACIDIFICATION (see PowerPoint file)