ocean water

Ocean WaterChapter 15

Section 1 Properties of OceanWater

Objectives:› List substances that are dissolved in

ocean water› Explain how a thermocline forms› Compare and Contrast properties of

ocean water› Predict the solubility of salt in water

at different temperatures

Skills Warm-up

What’s in Water?› Suppose that you have a glass of

pure water, a glass of fresh water, and a glass of salt water.

› If you evaporated the water, what would be left behind in each glass?

Origin of Ocean Water When earth first

formed, it was very ________

Active volcanoes sent ________ ________and ___________ out

One of the gasses was _________________

The released gasses gathered in a layer to become the __________________

Origin of Ocean Water After earth’s surface

cooled, the water vapor ________________ into droplets of water

Water droplets combined and fell to earth as _________

Rainwater flowed over earth’s surface and formed _________ and __________

Water then pooled in large connected basins – the _____________

Our Oceans 4 Oceans

› ___________› ___________› ___________› ___________

Pacific Ocean – largest ocean › covers ______ of the

earth › contains _______ of

earth’s salt water

Chemical Properties of Ocean Water Ocean water is a mixture

of dissolved› __________› __________› tiny amounts of many

__________ As rivers flow across

earth, these substances are picked up

When rivers reach the ocean, the substances are deposited as _________ ______ or used by _______ _____________

Chemical Properties of Ocean Water Major dissolved gasses

› ________ ________ ____________ Major dissolved salts

Salinity The number of _______ __ ______ in 1 kg of water Average salinity of ocean water is _________ Salinity varies from one part of the ocean to

another What causes high salinity:

› High _______________› Low _______________› ________________

What causes low salinity:› High _______________› Melting ____________› Where fresh water meets salt water (___________)

Parts of salt per 1000 parts ocean water

Physical Properties of Ocean Water _______________ Top of water column

directly heated by ______ – depth of 100 to 400 meters

Summer surface temps are _________ than winter

Temp varies from place to place – water is warmer near the __________ and cooler near the __________

Physical Properties of Ocean Water Just beneath the surface

water is a zone where water temp decreases rapidly - ______________

Thermocline forms because warm surface water ______ __ ____ ___ colder water

Depth of thermocline changes with the __________ and with ___________

Below the thermocline, water temp decreases only _____________

Ocean Water and Living Things

Organisms that live in the ocean use substances dissolved in ocean water to survive› _________ – use

dissolved nitrate for growth

› _____ __________– use calcium to build tough, thick shells

› _________ – use silica to build tiny, intricate shells

Ocean Water and Living Things

Many organisms depend on __________

For what???? Sunlight can’t

_______________ too far into ocean water

These organisms must live in _______ ________ near the shore or _________ on top of the water

Examples – algae and diatoms

Ocean Water and Living Things

Some organisms move up and down in the water column by changing their ________

Fish have a _________ ____________› Fill with gas from

bloodstream – fish is less dense – fish rises

› Empty swim bladder – fish is more dense – fish sinks deeper

Organisms that live in deep ocean water must withstand great _____________

Drinkable Ocean Water You shouldn’t drink ocean water – it has too

much _________ for your body to process You will actually get more ___________! Some areas of the world don’t have enough fresh

water They drink ocean water by removing the salt -

________________

Desalination Ocean water is pumped

into a chamber and __________

Water turns to __________ Steam is sent to another

chamber where it cools and _____________

Salt is too __________ and is left behind

Water from condensed steam is fresh and ________________

But fossil fuels need to be used to heat the water

Check and Explain 1. What substances are dissolved in ocean

water? 2. What is a thermocline? Explain how it

forms. 3. Explain the following properties of ocean

water: composition, temperature, salinity, and density.

4. Imagine you have a glass of water at room temperature. You mix salt into the water until no more will dissolve. Then you put the glass in the refrigerator. What will happen to the salt in the water?

Lab – “How Do Temperature and Salinity Affect Density?”

Text page 344

Section 2 Ocean Currents

Objectives:› Describe the major ocean current

patterns in the Pacific and Atlantic oceans

› Identify two factors that drive ocean currents

› Compare and Contrast surface currents and deep currents

› Predict the effects of the Coriolis force

Skills Warm-up

At the Edge› Imagine that you are riding in the

center of a merry-go-round. › You want to throw a ball to a friend

at the edge of the merry-go-round.› Where would your friend have to sit

to be able to catch the ball?

Ocean Currents If you were on a boat

adrift in the ocean near Antarctica, the boat would travel in a _____________ direction.

It would be carried along in a flow of water called a ____________

Current – a flow of water moving through the ocean

A strong current flows in a clockwise direction around _____________

Ocean Currents Currents flow through

all parts of the ocean _______ __________ – flow

horizontally at or near the top of the ocean

_______ __________ – flow horizontally far beneath the surface

Ocean water also flows _____________› Ocean water can flow

down toward the ocean floor or up toward the surface

Surface Currents Surface currents are

driven by _______ that blow for long distances over the ocean’s surface

The winds blow in a ________ ______ because of the Coriolis effect

__________ __________ – caused by the earth’s rotation, bends the earth’s winds and ocean currents

Ocean currents movie

Surface Currents and Wind Patterns

Earth rotates in an ___________ direction

Earth’s motion makes winds blowing toward the equator curve ____________

Winds blowing toward the poles curve ____________

Surface currents in the ocean form similar patterns

If winds change direction, so do surface currents

Surface Currents in the World Ocean ________ currents flow

from the equator ________ currents flow

from the poles Surface currents form

a circular pattern called a ________

Gyres in the northern hemisphere flow ________________

Gyres in the southern hemisphere flow ________________

Deep Currents The movement of surface

currents has little effect on _______ ________ __________

Deep currents are kept in motion by __________ differences

Cold water is the most dense and is at the ____________

This deep cold water flows toward the ___________, but the Coriolis effect bends them ______________

Deep Currents Where winds blow in a

constant direction parallel to the coast, surface currents and deep currents can mix

Wind pushes warm surface water _______ _____ ____ ________

______ _______ _________ moves up to take its place

_____________– the upward movement of deep water

Upwelling brings ___________ up from the ocean floor – attracts marine animals

Shoreline Currents Near shoreline,

_______ currents form that travel only __________ ______________

____________ _________ – when waves approach the shore at an angle and create a zigzag pattern parallel to shore

Shoreline Currents If there is a __________ or

___________, longshore currents can be trapped

Once it finds an opening, the longshore current breaks out forcefully

A narrow, powerful stream of water flows at a right angle to the shore – ______ __________

Very _______________ – swim parallel to shore

Shoreline Currents ____________ – forms

when water carried to the shore in waves pulls __________ toward the ocean

Usually it is not strong enough to be dangerous

But, if wave action is _________ or ocean bottom _______ _________ sharply, it can pull swimmers out to deeper water

Upwelling and Fisheries In areas of ___________,

winds blow warm surface water away from the coast

Cold, deep water moves in to fill the space

This cold, deep water contains large amounts of _____________ that support _________ and feed _________

These are the areas of the world’s most __________ fishing grounds

Upwelling and Fisheries Usually the upwelling

area along the ________ coast of S. A. is very productive

But, when ____ _________ comes, upwelling stops

El Nino is a disturbance of ocean currents and winds that occurs every _______ _______

It warms coastal waters, not allowing the nutrient rich colder waters up

No nutrients – no fish!

Check and Explain 1. Describe the surface currents in the

North Pacific Ocean and the North Atlantic Ocean.

2. What two factors cause ocean currents to form?

3. How do surface currents and deep currents differ? How are they similar?

4. What direction would a plane have to travel to reach a city directly south of its starting point if winds were blowing to the east? Why?

Section 3 Ocean Waves

Objectives:› Explain how waves form› Identify the parts of an ocean wave› Explain how to measure wave

motion› Define how a water particle moves

as a wave passes

Waves Ocean waves form when

_________ pushes against the ocean’s surface

_________ from the wind pushing makes ripples form

__________ is transferred from the wind to the water, making a wave

The _________ a wave surface becomes, the more energy it can absorb from the wind

Mechanics of Wave Motion When you watch a wave move, the

water appears to _______ __________ But, the water barely moves at all It is ______ ___________ that moves

forward, not the water particles Water particles actually move in a

circular __________________ motion

http://www.teachersdomain.org/ext/ess05_int_wavemotion/index.html

Characteristics of Waves Ocean waves form

_____ _______ ________ Wind blows over open

water causing unevenly space, ragged ______ ___ _________ to form

As the wave energy continues to travel, the waves form an even series of smooth, low hills of water called ____________

Wave Action and Energy As a wave gets closer to shore, its height

__________ and its wavelength ____________ As wave reaches shallow water some of the

wave energy transfers up increasing ______ _________

When wave contacts the ocean floor, friction slows down the deeper part of wave but wave crest keeps moving and ________ _________

Wave Action and Energy Waves carry a large amount

of _________ When a wave breaks all the

energy is ___________ against the shore

Can destroy property and disrupt boating and shipping

Can build a ___________ – high, sloping wall built at an angle to the shore

This forces waves to break away from the shore and it is protected from the full force of the waves

Earthquakes and Ocean Waves The most dramatic and

destructive ocean waves are caused by _______________

Earthquake causes part of the ocean floor to ______ ______

This pushes overlying water up, forming a ________ of water

As bulge settles down, it creates a series of _______ ___________

These ___________ waves can travel at speeds of over 700km/hour

Rogue Waves June 3, 1984 the Marques

sailing ship was sunk - 19 of its 28 crew members were lost

The cause was a _______ ________ that seemed to come out of nowhere

Rogue waves occur when two ordinary waves ___________

If their crests and troughs line up, their energy is added together and can form a wave up to ___ _________ __________

Check and Explain 1. How do ocean waves form? 2. Name the parts of an ocean wave. 3. Imagine you are on the deck of a boat

on a calm day. How can you determine the period of the waves passing under the boat?

4. Imagine a small piece of driftwood floating in the ocean. Describe its motion as a wave passes under it. What does this tell you about how a water particle moves as a wave passes?

Activity Tsunami move

Section 4 Tides

Objectives:› Describe the effect of gravity on

earth’s water› Explain why tides change› Compare and Contrast the different

types of daily tide patterns› Predict the effects of tides on fishing

Gravity and Ocean Water The sun and moon are large

objects that exert __________ _______ on the earth

_________ _________ shows the effects of gravity more than the solid earth

Every day the level of the ocean surface rises and falls because of the gravitational pull of the sun and the moon

________ – the daily changes in water level

Gravity and Ocean Water Gravitational pull of the

moon on the ocean is ________ on the side of earth _______ the moon

This causes the ocean to bulge on that side

On the side of earth ________ the moon, the moon’s gravity pulls the _____ ______ towards it and away from its ocean

This also causes a bulge

Gravity and Ocean Water As the earth rotates,

_____ _______ occur in areas of the earth’s surface beneath the bulges

______ _______– the highest level that ocean water reaches on the shore

Low tides occur in areas between the bulges

_____ ________– the lowest level that ocean water reaches on the shore

Daily Tide Patterns Every _______ ______ has at

least one high tide and one low tide every day

Factors that influence daily tide patterns› __________________________

______________________› __________________________

______________________› ________________________

Tide patterns repeat every 24 hours and 50 minutes

Because a complete cycle takes slightly ______ than a day, tides occur at different times

Daily Tide Patterns _____________________–

two high tides and two low tides each day› Atlantic coast of U.S.

_____________________ – one high tide and one low tide each day› Southeastern U.S.

along Gulf of Mexico ______________________–

mix of diurnal and semidiurnal tide patterns› Pacific coast of U.S.

Monthly Tide Cycles Tide heights can vary

each month ______________– daily tides

cycles with the greatest difference between high and low tides

______________ – daily tides cycles with the least difference between high and low tides

Periods of spring and neap tides occur twice each month and are caused by the changing positions of the sun and moon

Tides and Living Things Some organisms live on the

shore __________ the level of the highest tide and the lowest tide – must ___________› Sand dollars› Hermit crabs› Seaweed

As tide changes, they may be _________ with water or __________ to air and sun

Fish are also affected by tides and may come _________ to shore to feed during high tide

Grunion Life cycle of the grunion

fish depends on _______ __________

They swim onto the beach to _________ during the highest spring tides

They ________ their eggs in the sand, where they will develop until the next spring tide

The rising water stimulates the eggs to ________ and the young grunion swim out to sea

Tidal Power – Provides Energy Power plant at mouth

of ________ ________ in France

Huge _______ was built across the river with _________ beneath the surface for water to flow through

Inside the tunnels are large spinning _________

Spinning turbines operate _____________ that produce electricity

Check and Explain 1. How does gravity cause tides? 2. Why do tides change over the course

of a month? 3. What is the difference between a

semidiurnal tide pattern and a diurnal tide pattern?

4. When would a person going fishing on a beach have the best chance of catching a fish? Explain your answer.

Test Review Read Chapter 14 review – page 335

and complete:

› Check Your Vocabulary› Check Your Knowledge