Chapter 14 Unit Notes Lesson 1: Composition and Structure of Earth’s Oceans abyssal plain large, flat area of the seafloor that extends across the deepest parts of the ocean basin brackish describes freshwater mixed with seawater manipulate to operate by hand or by mechanical means photosynthesis chemical process that converts light energy, water, and carbon dioxide into sugar salinity measure of the mass of dissolved solids in a mass of water seawater has an average salinity of 35 parts per thousand

A. Earth’s Oceans 1. Earth’s oceans contain 97 percent of Earth’s water. 2. There are five oceans on Earth. a. The smallest and shallowest ocean is the Arctic Ocean. b. The largest and deepest ocean is the Pacific Ocean. 3. The water in the oceans came from several sources. As Earth formed, volcanic eruptions added water vapor to the air. a. As Earth cooled, the water vapor condensed into droplets that fell to Earth as precipitation. b. Another source of Earth’s oceans was melted ice from asteroids and comets that collided with Earth. 4. Minerals from rocks at Earth’s surface are carried into the ocean by rivers and streams. a. Salinity is a measure of the mass of dissolved solids in a mass of water. b. The average salinity of ocean water is 35 parts per thousand. c. Brackish water is freshwater mixed with salt water. B. The Seafloor 1. The continental margin is the area of the seafloor that stretches from the shoreline to the ocean basin. 2. The continental margin is divided into the continental shelf, the continental slope, and the continental rise. 3. Abyssal plains are large, flat areas that extend across the deepest parts of the ocean basins. a. Abyssal plains are covered with sediment. b. In some areas, underwater volcanoes rise from the abyssal plains and form islands. 4. A continuous chain of underwater volcanoes is called a(n) mid-ocean ridge. 5. A deep canyon that forms where plates collide is called a(n) trench. 6. Scientists use submersibles and other technology to study the seafloor. 7. The main resources from the ocean floor or beneath it are energy resources and minerals. Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

live live in this

s

wave height. as depth increases.

zone.

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salinity than the water water than the salinity

surface increases. decreases

greater circular.

the wind distance. blows, and

salinity than water beneath than it. The salinity water upper

when it collapses near the shore.

blowing over water. The size of a surface wave sizeblowing of a over The water. received.

time

less crest. trough. wind breaker sunlight

zone receives some sunlight, but not much.

zone receives no light.

middle deep Organisms Organisms that require sunlight for the process of zone. The The Most of the animals in the deep zone make light in the process of bioluminescence.

wavelength. Scientists divide oceans into zones based on water depth, temperature, salinity, As depth increases, the density of ocean water The zone that receives the most sunlight is the Surface water Earth’s has at poles water Surface layer of ocean water in tropical regions has has in tropical regions ocean of water layer it. beneath density, and the the and of amount density, a. b. c. d. rise and fall of the ocean’s surface caused by the gravitational force between Earth and the Moon, Moon, the and Earth between force gravitational the by caused surface ocean’s the of fall and rise In temperate and tropical regions, temperature difference in water level between a high tide and a low tide low a and tide high a between level water in difference occurs when Earth, the Moon, and the Sun form a straight line; has the largest tidal range tidal largest the has line; straight a form Sun the and Moon, the Earth, when occurs Surface waves are caused by the by caused waves are Surface the of on wind speed, length depends The motion of water particles in a wave is A surface wave becomes a(n) The lowest part of a wave is the The vertical distance between a crest and a trough two between horizontal or two isconsecutive distance The consecutivecrests troughs is the the The highest part of a wave is the 5. 4. 1. 2. occurs when Earth, the Moon, and the Sun form a right angle; has the lowest tidal range tidal lowest the has angle; right a form Sun the and Moon, the Earth, when occurs

3. wave that forms when an ocean disturbance suddenly moves a large volume of water of volume large a moves suddenly disturbance ocean an when forms that wave average level of the ocean’s surface at any given time given any at surface ocean’s the of level average Zones in the Oceans the in Zones 1. 2. 3. 2. 3. 4. 1. Parts of a Wave a of Parts Surface Waves Surface periodic periodic C. and Earth and the Sun the and Earth and B. A.

tsunami tsunami sea level level sea tide spring range tidal tide Lesson 2: Ocean Waves and Tides tide neap C. Tsunamis 1. A(n) tsunami is a wave that forms when an ocean disturbance suddenly moves a large volume of water. 2. A tsunami can be caused by a(n) earthquake, a volcanic eruption, landslides, or breaking glaciers. 3. Tsunamis can be quite high because they have long wavelengths. D. Tides 1. The average height of the ocean’s surface at any given time is called sea level. 2. Tides are the periodic rise and fall of sea level caused by gravitational forces that exist among Earth, the Moon, and the Sun. a. The largest tides are caused by the gravitational attraction between Earth and the Moon. b. The gravitational attraction between Earth and the Moon produces two bulges in the ocean’s surface. c. The area on Earth where the ocean bulges is experiencing high tide. d. The two thin areas of ocean on opposite sides of Earth are experiencing low tides. e. The difference in water level between high tide and low tide is the tidal range. f. Sea level is often measured as the average height of the ocean between high tide and low tide. g. When the Sun, the Moon, and Earth are aligned, spring tides occur. High tides are higher than normal, and low tides are lower than normal. h. When the Sun, the Moon, and Earth form a right angle, neap tides occur. High tides are lower than normal, and low tides are higher than normal.

Lesson 3: Ocean Currents Coriolis Effect movement of wind and water to the right or left that is caused by Earth’s rotation gyre circular system of currents ocean current large volume of water flowing in a certain direction upwelling vertical movement of water toward the ocean’s surface

A. Major Ocean Currents 1. A(n) current is a large volume of water flowing in a certain direction. 2. One cause of an ocean current is friction between wind and the ocean surface. a. A(n) surface current is an ocean current that moves water horizontally and does not reach a depth of more than 400 m. b. Earth’s prevailing winds influence the formation and direction of surface currents. c. In each ocean, major surface currents form a circular system of currents called a(n) gyre. Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

This

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source pollution. - source pollution. - warmer cooler sinks, sources, such as volcanic eruptions. activity.

Conveyor Belt Conveyor

term effects on the term effects point - upwells, rotation. Ocean and the and Ocean

natural human substance that causes a change in the health of

er that is cold and holds many is cold and that holds many er water water current are -

harmful water water current are Deeper water water Deeper

-

North Atlantic North air. sinks.

of nearby land can affect the direction and speed of currents.

are caused by differences in temperature or salinity, not winds. explosive growth of algae that harms other organisms

surface water, and then this warm water cools.and water surface water, then this warm

loss of color in corals that occurs when stressed corals expel the algae

d. topography Some ocean pollution comes from Most ocean pollution results from An oil spill from a ship is an example of Runoff from land is an example of nonpoint warms Coastal Coastal areas near a warm inland. farther Coastal areas near a cold inlan currents in the Density and in this model. energy water The model explains how cold, dense water Coriolis effect. results Earth’s Coriolis effect from The water and Earth’s of The Density increases with decreased temperature or that is dense Water with it. In addition to the wind, the direction surface currents flow depends on the on the surface currents flow depends direction the toaddition the wind, In

efers to anything related to the oceans or water

r environment. the ocean. a. b. c. d. a. b. b. carry Earth’s oceans. through energy currents b. a. f. brings movement up wat vertical a. d. e. large growth of algae Scientists use a model called the Great Ocean Ocean the Great model called Scientists a use Sometimes ocean currents have vertical movement, which is called movement, vertical currents is called have which Sometimes ocean Ocean currents affect climate because they carry moisture and Ocean pollution includes any Ocean pollution can have immediate and long have and immediate pollutionOcean can Density currents 2. 1. 2. 3. 1. Impacts on Weather and Climate 4. Ocean Pollution Ocean harmful algal bloom marine A. Lesson 4: Environmental Impacts on Oceans bloom coral bleaching that live in them B.

C. B. Keeping Oceans Healthy Oceans and GlobalOceans Change Climate and 1. 1. 4. 3. 3. 2. 1. 3. 2. 5. 5. Solid Climate data show that Earth’s showthat surface data Climate has temperature Erosion can wash excessive amounts of of amounts excessive wash can Erosion

income for humans. Oceansand mineral provide O provide Oceans distribute Oceans seawater, in dissolves dioxide carbon When and The amount of c. b. a. the past century. c. b. a. b. a. b. a. organisms. Ocean organisms require require organisms Ocean b. a. 2

weaker. include Thesethealgae producemuchof organisms Earth’s that calcium.

during When marineWhen absorb organismslesstheir shellsandskeletons calcium, get Increasing acidiwater in it dissolved oxygen of amount the increases, water ocean of temperature the When Increasi their tissues. the expel corals make can temperature in change small a Even organisms. the of much up uses are they die, algae When wash from phosphates and nitrates excess of result the often are blooms Algal reproduce greateraverage. innumbers than much harmful A(n) keeps also sediment Excess filter Sediment canuse to clog as thestructures thatorganismsclams such andsponges Great Garbage Pacific Patch. The to try animals Many oxygen

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sunlight

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resources and servearesources source of as and

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carbonic acid carbonic level.

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Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.