Ocean Water, Chapter 20, Earth Science 7

reverse osmosis deslination

uses special membranes that allow water under high pressure to pass through and block dissolved salts

three main sources that form sea salts

volcanic eruptions, chemical weathering of rock on land, and chemical reactions between sea water and newly formed sea-floor rocks

freezing

when water freezes, the first ice crystals formed have no salt and can be removed and melted to get fresh water

intertidal zone

the shallowest benthic zones that lies between the low-tide and high-tide lines

ocean water density range

1.026 g/cm^3 and 1.028 g/cm^3

average salinity of the global ocean

34.7%

dissolved solids composition

55% chlorine, 30.6% sodium, 7.7% magnesium, 3.7% sulfur, 1.2% calcium, 1.1% potassium, and 0.7% trace elements

ocean's contents

96.5% pure water 3.5% dissolved solids (sea salts)

pack ice

a floating layer of sea ice that completely covers and area of the ocean surface; usually no more than 5 m thick

thermocline

a layer in a body of water in which water temperature drops with increased depth faster than it does in other layers; usually present beneath the ocean surface

salinity

a measure of the amount of dissolved salts in a given amount of liquid; measured by the number of grams of dissolved solids in 1000 g of ocean water

carbon sink

a name given to the ocean due to its ability to dissolve and contain large amounts of CO2

desalination

a process of removing salt from ocean water

nekton

all organisms that swim actively in open water, independent of currents

bathyal zone

begins at the continental slope and extends to a depth of 4000 m; plant life is scarce

hadal zone

confined to the ocean trenches; deeper than 6000 m below the surface of the water; virtually unexplored; life is sparse

sublittoral zone

continuously submerged zone located on the continental shelves populated by organisms

color of the ocean

determined by the way the ocean absorbs or reflects sunlight; water absorbs every wavelength except for blue which is reflected which makes the ocean seem blue

three methods of desalination

distillation, freezing, and reverse osmosis deslaination

trace elements

elements in the dissolved solids that exist in small amounts (gold, zinc, and phosphorus)

oceanic zone

extends into the deep waters beyond the continental shelf; has 4 zones: epipelagic, mesopelagic, bathypelagic, and abyssopelagic zones

abyssal zone

has no sunlight; begins at a depth of 4000 m and ends at 6000 m

distillation

heating ocean water to remove salt; the heat causes the water to evaporate and leaves the salts behind and when the vapor condenses, you're left with fresh water

phytoplankton

microscopic plants in the ocean that provide food to many of the ocean's organisms; absorb red and blue light; reflect green light

benthos

organisms that live at the bottom of oceans or bodies of fresh water

nodules

potato-shaped lumps of minerals found on the abyssal floor of the ocean; a valuable source of manganese, iron, copper, nickel, cobalt, and phosphates

properties to describe ocean water

presence of dissolved gases, presence of dissolved solids, salinity, temperature, density, and colour

two factors that affect the density of ocean water

salinity and the temperature of the water

deep water

temperature is 2C; holds more dissolved gases than warm, shallow water

neritic zone

the area of the pelagic zone above the continental shelves; has abundant sunlight, moderate temperatures; and slow water pressure

benthic zone

the bottom region of oceans and bodies of fresh water

two factors that most marine organisms depend on for survival

the essential nutrients available in ocean water and sunlight

plankton

the mass of mostly microscopic organisms that float or drift freely in the waters of the aquatic (freshwater and marine) environments

upwelling

the movement of deep, cold, and nutrient-rich water to the surface

aquaculture

the raising of aquatic plants and animals for human use or consumption

density

the ratio of the mass of a substance to the volume of the substance; solids and liquids: gram per cubic cm; gases: grams per liter

pelagic zone

the region of an ocean or body of fresh water above the benthic zone