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Glossary of Chemical Oceanography Terms
Meteorites: Extraterrestrial material that reaches the earth from outer space; forms
cosmogenous sediment.
Mixed Estuary: An estuary with a shallow basin where the water is well mixed. This
leads to similar salinities throughout the water column. The salinity increases as
the water flows from the head to the mouth.
Mixed Layer: Upper layer of ocean surface waters (5 to 200 m) where the properties are
homogenous because of mixing caused by wind stress.
Monsoon Current: Replaces the North Equatorial Current during monsoon season
(May–September); driven by the monsoon winds. The current also causes the
Equatorial Countercurrent to disappear.
Mouth: The portion of an estuary closest to the sea.
Negative Estuary: An estuary of high salinity caused by evaporation greater than precipitation and river runoff.
North Atlantic Current: A warm current that is a continuation of the Gulf Stream; highsalinity waters that flow northeasterly in the North Atlantic. It divides into the
Norwegian Current going north and the Canary Current going south.
North Atlantic Deep Water (NADW): Major water mass in the Atlantic Ocean. Formed
in the Norwegian Sea and flows in pulses over sills between Scotland, Iceland, and
Greenland (S = 34.9, t = 2 to 3°C).
North Equatorial Current: Flows westward from North Africa to the Gulf Stream driven
by northeast trade winds (45 Sv, with surface speeds of 25 to 30 cm s –1 ).
Norwegian Current: Continuation of a portion of the North Atlantic Current flowing
between the Shetland and Farrel Islands northward into the Norwegian Sea.
Oyashio Current: A cold current that flows northeast along the eastern Asia coast.
Peru Current: A cold, slow, and shallow water current flowing north off the west coast of
South America.
Polar Cells: Air circulation caused by sinking air at the poles and rising air at high latitudes (60 to 90° latitude).
Polar Front: An area characterized by strong temperature gradients. Warm and cold air
converge in the Polar Front Zone (approximately 55 to 60° N and further north).
Positive Estuary: An estuary of low salinity caused by precipitation and river runoff greater
than evaporation.
Potential Temperature: Temperature of seawater corrected for the effects of pressure. The
application of pressure (depth) to seawater causes the temperature to increase.
Practical Salinity: The salinity determined from conductivity measurements. It has no
units since it is a ratio of conductance of an unknown and a standard. It has and
still is denoted as S and should be denoted as S P . For average seawater, S P = 35.00,
and the reference or absolute salinity is 35.16504 g/ kg for surface water with
little silica.
Precipitation: Formation of a solid from solution by physical or chemical processes.
Formation of rain, hail, snow, or mist from cloud water. Causes the salinity to
decrease and accounts for the lower salinities near the equator.
Profile: The plot of a physical or chemical property (S, O 2 ) as a function of depth.
Pycnocline: A depth layer of ocean where density increases rapidly, preventing vertical
mixing because of rapid changes in temperature or salinity.
Red Sea Water: Warm, saline (S = 42.5) water that flows from the Red Sea into the northern, western Indian Ocean. Flows to a depth of 1000 to 1500 m. Lower salinity and
temperature are found once the water exits the Red Sea due to mixing.
Glossary of Chemical Oceanography Terms
Meteorites: Extraterrestrial material that reaches the earth from outer space; forms
cosmogenous sediment.
Mixed Estuary: An estuary with a shallow basin where the water is well mixed. This
leads to similar salinities throughout the water column. The salinity increases as
the water flows from the head to the mouth.
Mixed Layer: Upper layer of ocean surface waters (5 to 200 m) where the properties are
homogenous because of mixing caused by wind stress.
Monsoon Current: Replaces the North Equatorial Current during monsoon season
(May–September); driven by the monsoon winds. The current also causes the
Equatorial Countercurrent to disappear.
Mouth: The portion of an estuary closest to the sea.
Negative Estuary: An estuary of high salinity caused by evaporation greater than precipitation and river runoff.
North Atlantic Current: A warm current that is a continuation of the Gulf Stream; highsalinity waters that flow northeasterly in the North Atlantic. It divides into the
Norwegian Current going north and the Canary Current going south.
North Atlantic Deep Water (NADW): Major water mass in the Atlantic Ocean. Formed
in the Norwegian Sea and flows in pulses over sills between Scotland, Iceland, and
Greenland (S = 34.9, t = 2 to 3°C).
North Equatorial Current: Flows westward from North Africa to the Gulf Stream driven
by northeast trade winds (45 Sv, with surface speeds of 25 to 30 cm s –1 ).
Norwegian Current: Continuation of a portion of the North Atlantic Current flowing
between the Shetland and Farrel Islands northward into the Norwegian Sea.
Oyashio Current: A cold current that flows northeast along the eastern Asia coast.
Peru Current: A cold, slow, and shallow water current flowing north off the west coast of
South America.
Polar Cells: Air circulation caused by sinking air at the poles and rising air at high latitudes (60 to 90° latitude).
Polar Front: An area characterized by strong temperature gradients. Warm and cold air
converge in the Polar Front Zone (approximately 55 to 60° N and further north).
Positive Estuary: An estuary of low salinity caused by precipitation and river runoff greater
than evaporation.
Potential Temperature: Temperature of seawater corrected for the effects of pressure. The
application of pressure (depth) to seawater causes the temperature to increase.
Practical Salinity: The salinity determined from conductivity measurements. It has no
units since it is a ratio of conductance of an unknown and a standard. It has and
still is denoted as S and should be denoted as S P . For average seawater, S P = 35.00,
and the reference or absolute salinity is 35.16504 g/ kg for surface water with
little silica.
Precipitation: Formation of a solid from solution by physical or chemical processes.
Formation of rain, hail, snow, or mist from cloud water. Causes the salinity to
decrease and accounts for the lower salinities near the equator.
Profile: The plot of a physical or chemical property (S, O 2 ) as a function of depth.
Pycnocline: A depth layer of ocean where density increases rapidly, preventing vertical
mixing because of rapid changes in temperature or salinity.
Red Sea Water: Warm, saline (S = 42.5) water that flows from the Red Sea into the northern, western Indian Ocean. Flows to a depth of 1000 to 1500 m. Lower salinity and
temperature are found once the water exits the Red Sea due to mixing.