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