Download Notes-Ocean Water

Notes-Ocean Water
Ocean water is a complex mixture of plants, ______________, dissolved solids and
gases. Ocean water, and water in general, have physical properties such as temperature,
density, and ______________ that help describe it. Scientists study these characteristics
and the interactions among the ________________, the atmosphere, and the land.
Salinity
Every year the earth’s rivers carry about _____ billion metric tons of dissolved solids into
the oceans. The chemical weathering of rocks on continents is one source of elements
found in seawater. Most of these dissolved solids are ________. _________ also enter
the water out of the atmosphere or by undersea volcanoes. The amount of dissolved
materials has stayed balanced for millions of years because of the organisms that live off
these materials. About 4 billion years ago the Earth cooled enough for the moisture in
the atmosphere to condense and torrential rains filled the ocean basins. Ocean water is
____% pure water. The other 3.5% are elements like ______________, sodium, sulfur,
calcium, magnesium, and potassium. Other trace solids such as gold and zinc exist in
small amounts. The most abundant gases in the atmosphere are the most abundant gases
dissolved in the ocean, Nitrogen, Oxygen, and _______________ ______________
which Carbon dioxide is most easily dissolved in water. Temperature affects the amount
of gas that dissolves in water. Gases dissolve better in _________ water. Dissolved
gases can also be released back into the atmosphere.
Dissolved solids make up about ____% of the mass of ocean water. Sodium chloride,
normal table salt NaCl makes up 78 % of the oceans dissolved solids. The amount of
dissolved solids present in ocean water is described by it’s ________________ because
most of the solids in ocean water are salts. Both ________________________ and
___________________ increase the salinity of ocean water. This is why tropical waters
have a higher salinity than polar waters. There is also more salinity on the surface than at
greater depths. Ocean water ranges anywhere from 38 or more parts per 1000 to 32 or
less parts per 1000. The salinity stays constant because there is so much
______________________ running into oceans.
Ocean Temperature
Ocean water also absorbs solar energy depending on which ______________ the
water sits. Near the equator ocean temperatures are ________________ than polar
oceans because of the amount of direct sunlight received. The boundary between warm
surface water and cold deep water is called a _______________________. As the depth
of ocean water increases the temperature decreases. The ___________ of water is blue
because that is the only color of light reflected by the water. The rest of the colors are
absorbed.
Ocean Density
Density is how heavy something is for its size. The density of sea water determines
whether the water floats or _____________. Seawater is more dense than fresh water.
Seawater density is influenced by two factors _________________ and temperature.
As ocean temperature decreases the density increases. The ocean is divided into ___
layers based on its density a shallow surface mixed zone, a transition zone, and a deep
zone.
Life in the Oceans
Living organisms in the ocean depend on two major factors: essential nutrients in the
water and __________________. Nearly all life in the ocean is regulated by the life
processes of ________________. Animals and plants help maintain a balance of
nutrients and gases that are required for them to live.
When surface water is blown by the wind, deep nutrient-rich water moves up to take its
place this is called ____________________. Plants grow only in the top 100m of the
ocean because the sun can only penetrate to about 200m. Marine organisms are classified
according to where they live and how they move. Microscopic plants and animals called
plankton serve as the base of food in the oceans. Plankton includes all organisms like
algae, animals and bacteria that drift with the ocean currents. Larger animals called
_____________ are those that move independently of the currents usually by swimming.
Benthos refers to those animals that live on the ocean bottom. The ocean is divided into
life zones by three factors, the availability of sunlight the ________________ from shore
and water ______________. The benthic environment is the bottom or ground zone.
This zone is broken up into 5 zones based on the amount of light and organisms that live
there. The pelagic zone is the open ocean and has a photic zone near the surface and an
aphotic zone at about 200 meters down.