a measure of how hot or cold something is; a measure of the average kinetic energy of the particles of a substance.
absorbs solar radiation that heats the water.
the degree of saltiness of a salt solution, especially applied to ocean water. On average, the salinity of the world's oceans is 35 ppt.
the mass of an object divided by its volume; the colder the water, the higher its density. Maximum density would be 4°C. The saltier the water, the more dense it is.
Temperature and salinity
influence the density of seawater.
96.5% water, 55.0% chloride, 30.6% sodium, 7.7% sulfate, 3.7% magnesium, 1.2% calcium, 1.1% potassium, and 0.7% other ions (strontium, bromide, carbon).
measures electrical conductivity, which is related to salinity.
determines depth, usually by barometric pressure.
sample water at different depths.
a hydrothermal vent at the crest of an oceanic ridge; volcanic activity undersea.
water evaporating from the sea surface.
the alkalinity of seawater causes chemicals such as carbonates, phosphates, and manganese to precipitate.
Calcium carbonates are incorporated into the shells of microscopic marine plants and animals.
In water, a distinctive temperature transition zone that separates an upper layer that is mixed by wind (the epilimnion) and a colder, deep layer that is not mixed (the hypolimnion)
layer of water that shows rapid increase in salinity. 100-200 meters deep
Depth zone within which seawater density changes.
Movement of ocean water caused by density difference brought about by variations in temperature and salinity. As ocean water freezes at the poles it concentrates salt, and the colder, denser water sinks.
(0v150 m): well-mixed waters where velocity increases mainly due to increased pressure (pressure is affected by density)
(150v1,000 m): waters where sound velocity decreases due to decreasing temperatures
(below 1,000 m): waters where sound velocity increases due to increased pressure and relatively constant temperature
Because seawater absorbs light, light can only penetrate to a depth of about 200 m. However, not all wavelengths penetrate equally. Red light gets absorbed first, followed by orange and ultraviolet, and then yellow. After about 50 m, the only colors remaining are blue and blue-green. The result is that the color of an object you would see underwater would depend upon the depth.
Below 200 m, the ocean is black because no light from the surface reaches these depths.
the ocean bottom
tiny, free-floating organisms that occur in aquatic environments
the aggregate of actively swimming animals in a body of water ranging from microscopic organisms to whales
microscopic one-celled plants that grow in marine and fresh water; they secrete walls of silica in a variety of forms that accumulate in sediments.
not using oxygen; when applied to organisms, cells, or tissues, it means they do not use oxygen as part of the process of obtaining energy from glucose.