Tab 2 – BLUE – Salinity (C76-77)
1. Sodium chloride (salt) is the most plentiful compound in the ocean.
2. Salinity is a measure of the amount of dissolved salt contained in water.
3. The ocean is salty because of underwater volcanic eruptions and because rain and rivers
wash the elements that make up salt into the ocean (these elements are found in rocks
and minerals).
4. The higher water’s salt content, the greater its density; therefore, salt water has a higher
density than freshwater.
5. Salinity increases when water evaporates from the ocean and leaves behind salt causing
the water to become even saltier. Also, when water freezes into ice it leaves behind the
salt in the water below.
6. Salinity decreases in areas diluted by freshwater, as in an estuary, and in areas with lots of
rain fall.
7. The overall salinity of the ocean remains constant because salt is both added and removed
by natural processes (the water cycle, volcanic eruptions, etc.).
Tab 3 – PINK – Dissolved Gases (C78)
1. The three major dissolved gases that are essential to ocean life are oxygen (O2), nitrogen
(N2), and carbon dioxide (CO2).
2. Carbon dioxide is used when plants and algae use sunlight to convert it and water into
food, and release oxygen into the water.
3. The oxygen in the ocean comes from the air above the ocean surface and from plants as a
waste product of photosynthesis.
Tab 4 – YELLOW – Temperature (C79)
1. The ocean is divided into three layers based on temperature:
 The surface layer is heated by the sun and mixed by winds and waves. It is the
warmest layer. Warm water stays at the surface because warm water is less
dense than cold water.
 The thermocline lies below the surface layer, and the temperature of the water in
this layer drops fast with depth.
 The deep water is cold all year (at or barely above freezing), even in the tropics.
2. The temperature of the water at the surface of the ocean varies by location and season.
The surface layer is warmer nearer the equator than near the poles. Over much of the
Earth, the surface layer is warmer in the summer and cooler in the winter.
Tab 5 – WHITE – Ocean Floor (C80-81)
1. The ocean bottom along coastlines is called the continental shelf. A continental shelf is the
flat or gradually sloping land that extends underwater from the edge of a continent to a
continental slope.
2. A continental slope is a land feature that drops steeply at the edge of the continental shelf.
3. The features that lie beyond the continental slope include:
 huge submarine canyons that slice through the continental slope and shelf,
 flat abyssal plains (wide, flat areas of the ocean floor that are covered with a thick
layer of sediment) that cover huge portions of the deep-ocean floor



mid-ocean ridges are chains of mountains (the world’s longest mountain range) that
run through an ocean basin
seamounts are underwater mountains
volcanic islands are underwater volcanoes that are tall enough to reach above the
surface of the water
Tab 6 – WHITE – Ocean Exploration (C81-82)
1. As you go deeper in the ocean, the pressure of the water increases, and the more crushing
the weight of the water becomes.
2. Besides pressure, three other obstacles to ocean exploration are darkness, lack of air, and
chilling cold.
3. Three things scientists use to explore the ocean include:
 scuba equipment that allows a diver to spend about an hour underwater and
reach depths as great as 40 meters (130ft)
 small submarines to go even deeper
 robots equipped with cameras that offer views of areas too deep or difficult
for humans to reach
4. Two methods used in mapping the ocean floor are sonar (a system that uses sound waves
to measure distances and locate objects) and satellite imaging (used for mapping large
areas by detecting tiny bumps and dips in the ocean’s height to reveal the shape of the
ocean floor).
Tab 7 – YELLOW – Ocean Currents
1. An ocean current is a mass of moving water.
2. Surface currents are caused by strong winds blowing over the ocean; these winds are
caused by the uneven heating of the Earth’s surface. These currents move warm water
from the equator and cool water away from the poles. They extend only about 100-200
meters (300-500ft) down into the ocean.
3. The two factors that affect the paths of surface currents are the Earth’s rotation (clockwise
in the Northern Hemisphere and counterclockwise in the Southern Hemisphere) and the
shapes of the continents.
4. Deep currents are driven by differences in water density; dense water sinks in the ocean.
Water becomes more dense because of cooling, an increase in salinity, or both. Warm
water rises because it is less dense than cold water.
5. Downwelling is the movement of water from the surface to greater depths. As the water
sinks, it carries oxygen down from the surface.
6. Upwelling is the movement of water up to the surface; this brings up nutrients from the
deep ocean.
7. Surface currents help distribute heat around the globe by moving warm water away from
the equator and cool water away from the north and south poles.
8. The Gulf Stream affects Great Britain by carrying warm water from the Gulf of Mexico
northeastward toward Europe. Due to the warm Gulf Stream waters, Great Britain has a
mild climate.
9. An El Niño occurs every three to seven years when the winds in the Pacific Ocean do not
blow as strongly as usual. Without the winds, this disrupts the movement of currents in
the Pacific. During El Niño years, weather patterns change around the planet. Some places
get more or less rain or snow than usual, and temperatures may be warmer or cooler than
in other years.
Tab 8 – PINK – Waves
1. Definitions:
 crest – the high point of the wave
 trough – the low point of the wave
 wave height – the vertical distance between the top of the crest and the bottom of
the trough
 wavelength – the distance between one wave crest and the next
 frequency – the number of waves passing a point in a certain time
2. As waves get closer to the shore:
 wave height increases
 wavelength shortens, and
 frequency slows (the waves slow down).
3. Rip currents are narrow streams of water that break through sandbars and drain rapidly
back to sea. They occur when high winds or waves cause a larger-than-usual amount of
water to wash back from the shore.
4. A longshore current moves water parallel to the shore. They occur in places where waves
meet the land at an angle rather than head-on (which occurs on almost every shore).
Tab 9 – BLUE – Tides
1. A tide is the periodic rising and falling of the ocean’s water level.
2. Three factors that cause the tides include the gravity of the moon, the gravity of the sun,
and the Earth’s rotation.
3. Most places experience two high tides and two low tides each day.
4. Some of the benefits of tidal power plants include using the energy of tides to generate
electricity causes much less pollution than many other methods, and tides are a
renewable source of energy because they are not used up in the process. Some of the
drawbacks of tidal power plants include there being few places in the world suitable for
such dams, disrupting/blocking the paths of migrating fish, hurting marine life by altering
the regular flow of water, and not always generating electricity at the times of day when
people most need it.
Tab 10 – GREEN – Ocean Zones
1. Define the following terms:
 intertidal zone – zone closest to shore; at high tide it is covered with water, and at
low tide it is exposed to air
 neritic zone – lies over the continental shelf; water is not very deep; there are plenty
of nutrients and sunlight; many organisms live in this zone
 oceanic zone – the open ocean out past the continental shelf; the water may be
quite deep; nutrients may be scarce; fewer organisms live in this zone
 photic zone – is the top 200 meters of water; has enough sunlight for
photosynthesis, so it contains more living things than the aphotic zone
 aphotic zone – the water below 200 meters; there isn’t enough sunlight for
photosynthesis, so l living things must eat whatever drifts down from above or eat
each other; fewer living things live in this zone than near the surface
 benthic zone – is on the ocean floor (which drops as you move away from the
continents); there are few organisms that live on the ocean floor where the water is
very deep
2. Four characteristics of environments near the shore are sunlight reaches most of the way
to the ocean bottom, nutrients wash in from land, temperature and salinity are nearly
constant from the surface to the bottom, and these conditions support many kinds of
living things.
3. Open ocean conditions differ from those found close to the shore in many ways:
 sunlight reaches through only the very top part of the open ocean,
 nutrients sink down to the dark depths,
 there are no rocks, reefs, or big plants to provide shelter from predators,
 there are fewer living things than in the waters near the shore, and
 life is more spread out