Water in Earth’s
Processes
Lesson 10
A Wet Planet
EQ: How is Earth’s
water distributed
among saltwater and
freshwater?
How is Earth’s water distributed
among saltwater and freshwater
• Some people call Earth the “blue planet”
because over 70% of Earth’s surface is covered
with water.
• Most of Earth’s freshwater is found in the
polar ice caps near the North and South Poles.
• From largest to smallest, the amounts of water
on Earth are salt water (97%), solid fresh
water (2%), liquid fresh water (1%).
Salt Water
• Most of the water on Earth is in Earth’s
oceans
• Oceans contain salt water.
• The salinity, or salt concentration,
averages about 3.5%, or 35 grams of salt
per kg of water.
• In order of size from largest to smallest,
Earth’s oceans are the Pacific, Atlantic,
and Indian Oceans.
Fresh Water
• Most of the Earth’s freshwater is located in
the polar caps.
• Lakes, rivers, streams, and glaciers hold the rest
of Earth’s surface freshwater.
• A glacier is a very slow moving river of ice.
• A large portion of the rest of Earth’s freshwater
is trapped between underground layers of
rock. This trapped freshwater is called
groundwater.
Quick Check
About how much of Earth’s surface is
covered by water?
A. 0%
B. 30%
C. 70%
D. 100%
Quick Check
From the largest to smallest, the amounts of
water on Earth are
A. liquid fresh water, solid fresh water, salt
water.
B. salt water, solid fresh water, liquid fresh
water.
C. salt water, liquid fresh water, groundwater.
D. groundwater, salt water, solid fresh water.
Quick Check
A glacier is
A. a river of liquid water.
B. an ice cap.
C. a solid lake.
D. a slow river of ice.
Lesson 25
Sun, Wind, and
Water
EQ: How does a drop of
water move through the
water cycle?
Wind
• Earth receives heat energy from the sun through
Radiation.
• Radiation is the movement of energy through
empty space.
• Air at different places on Earth heats up unevenly.
The uneven heating up of Earth’s air is what
produces wind.
• Cool air moves toward warmer air. Warm air moves
away from cooler air. Moving air is wind.
Water
• Very little water is ever lost on Earth
• The sun is the source of energy that
drives the water cycle.
• Energy from the sun causes the water
particles to move faster and escape
into the air as water vapor.
Water
• Water vapor rises into the air and cools down.
•
•
•
The water molecules move slower and come
closer together, or condense. This is called
condensation.
Condensation forms clouds and precipitation
such as rain, sleet, hail, and snow.
The precipitation falls to the ground and
gathers there in puddles, ponds, rivers, lakes,
and oceans. (Accumulation)
Some water seeps into the ground and collects
there. This underground water is called
groundwater. (runoff)
Water
• Some groundwater finds its way into oceans.
• Water on the surface is warmed again by the
sun and will evaporate. So will water in the soil.
• Water vapor also enters the air from plants.
This is called transpiration.
• This keeps the water cycle going.
Quick Check
What is the source of energy that produces
winds and causes evaporation?
A. lightning
B. Earth’s rotation
C. the moon
D. the sun
Quick Check
Heating liquid water produces
A. snow.
B. rain.
C. water vapor.
D. groundwater.
Quick Check
The sun’s energy reaches Earth through
A. evaporation.
B. condensation.
C. radiation.
D. wind.
Quick Check
What process produces rain?
A. condensation
B. evaporation
C. warming
D. solidification
Quick Check
Water vapor is a
A. liquid
B. solid
C. gas
D. form of energy
Quick Check
The cooling of water vapor leads FIRST to
A. cloud formation.
B. evaporation.
C. formation of groundwater.
D. precipitation.
Quick Check
What process produces a cloud?
A. Evaporation
B. Condensation
C. Radiation
D. warming
Lesson 11
The World’s Oceans
• EQ: How does the
composition and topography
of earth’s oceans vary by
location?
Location of the World’s
Oceans
• The Pacific Ocean is the largest ocean. It is
bordered by North America, South America,
Asia, Australia, and Antarctica
• The Atlantic is the second largest ocean. It
is bordered by N. America, S. America,
Africa, Europe, and Antarctica.
• The third largest ocean is the Indian Ocean.
It lies between the countries of India,
Pakistan, Australia, and the continents of
Africa and Antarctica.
Composition of the World’s
Oceans
• The main substance dissolved in ocean water is
sodium chloride (NaCl) or table salt.
• Other dissolved solid substances are sulfate,
magnesium, calcium, and potassium.
• Solid substances dissolved in sea water come
from rivers, streams, rocks from the shore,
volcanoes and underwater hot springs.
• The concentration of all the dissolved
substances in sea water is about 3.5%.
Composition of the World’s
Oceans
• The oceans also hold dissolved gases,
such as oxygen and carbon dioxide.
• Marine life such as fish need dissolved
oxygen in sea water to live.
• Sea plants such as seaweeds need carbon
dioxide to survive. They get it from the
dissolved carbon dioxide in sea water.
Topography of the World’s
Oceans
• Oceanographers have mapped the ocean
floors by using special equipment.
• Echo sounding, (pings), measure the time
it takes a pulse of sound to go from the
ship to the ocean floor and echo back to
the ship.
• The speed of sound in sea water averages
about 1520 m per second.
Quick Check
Which continents border the Atlantic Ocean?
A. North America, South America, Asia, Australia
B. Asia, Australia, Africa
C. North America, South America, Europe, Africa
D. South America, Europe, Asia, Australia
Quick Check
Which substance do fish need to live and
take in from water that you take in from
air?
A. salt
B. oxygen
C. carbon dioxide
D. water
Quick Check
Pings from an echo sounder aboard a ship
make a round trip in 8 seconds. How far
beneath the ship is the ocean floor?
A. 2,920 meters
B. 6,080 meters
C. 11,680 meters
D. 23,360 meters
Quick Check
Which shows the order of Earth’s three
major oceans from largest to smallest?
A. Pacific, Atlantic, Indian
B. Atlantic, Pacific, Indian
C. Indian, Atlantic, Pacific
D. Atlantic, Indian, Pacific
Quick Check
If you were to walk along the ocean bottom
from a beach, which of the following
features would you reach after the
continental shelf?
A. the abyssal plain
B. a seamount
C. the mid-ocean ridge
D. the continental slope
Quick Check
About how deep is the deepest pat of the
world’s oceans?
A. 4000 meters
B. 8000 meters
C. 11,000 meters
D. 14,000 meters
The Water Cycle
Section 11-1
• How is Earth’s water
•
•
distributed among
saltwater and
freshwater resources?
How does Earth’s
water move through
the water cycle?
How do people and
other living things use
water?
Water on Earth
• Most of Earth’s water is saltwater (97%)
• Most saltwater is found in the oceans
• Only about 3% of water is freshwater
• All living things must share about 1% of
the total amount of water on Earth
Distribution of Water on Earth
• Saltwater oceans and lakes (97%)
• Freshwater (3%)
– Ice (76%)
– Shallow Groundwater (12%)
– Deep Groundwater (11%)
– Lakes and rivers (.34%)
– Water Vapor (0.037%)
• All living things share less than 1% of total
water on Earth!
The Water Cycle 1
• Water is naturally recycled through a
process known as the water cycle
• Water moves from bodies of water, land,
and living things from Earth’s surface, up
to the atmosphere and then back to
Earth’s surface.
• Steps for the water cycle are: evaporation,
condensation, and precipitation
The Water Cycle 2
• The source of energy that drives the water
cycle is the SUN!
• Clouds formation – water vapor loses
energy, cools down, condenses into liquid
water droplets, droplets clump together
around tiny dust particles, forming clouds
• Most evaporated water comes from
oceans, and most precipitation falls back
into the oceans
The Water Cycle 3
• Evaporation – the process by which liquid
water on the surface change to a gas
• Condensation – process by which gas
molecules change into a liquid. This
process forms clouds
• Precipitation – process in which clouds
become too heavy to hold the water
droplets, and the droplets fall to the
Earth’s surface as rain, sleet, snow or hail
How Do People Use Water?
• Humans use water for household purposes,
•
•
•
•
agriculture, industry, transportation, and
recreation.
Irrigation is the process of supplying water to
areas for growing crops
Industry – to make products, cool off
machines
Transportation – travel upon the oceans,
lakes and rivers
Recreation – exercise and sports
Water and Living Things
• Water important for living things to grow,
reproduce and carry on other essential
processes.
• Photosynthesis – process of water, carbon
dioxide and sunlight to make their own
food
• Habitat – place an organism lives and
provides the things it needs to survive
Quick Check
More than 97% of Earth’s total water supply
is found in
A.
B.
C.
D.
ice sheets.
groundwater.
the atmosphere.
the oceans.
Quick Check
The energy the drives the water cycle
comes from
A. the sun.
B. the Earth.
C. the rain.
D. oceans.
Quick Check
Rain that falls on a steep, paved street
during a thunderstorm will most likely
become
A.
B.
C.
D.
groundwater.
runoff.
a spring.
a reservoir.
Quick Check
More than two-thirds of Earth’s freshwater is
found in
A.
B.
C.
D.
rivers and streams.
ponds and lakes.
glaciers and icebergs.
wetlands.
Quick Check
How does the water cycle renew Earth’s
supply of fresh water?
A.
B.
C.
D.
evaporation.
condensation
the sun
precipitation
Ocean Water Chemistry
• How salty is ocean water?
• How do the conditions in
the ocean change with
depth?
• Describe one factor that
increases the salinity of
seawater and one factor
that decreases salinity.
The Salty Ocean
• The average amount of salt in ocean water is
•
•
•
•
about 3.5% or 35 grams of salt per one kilogram
of water
Ocean water carries many different dissolved salts
Sodium Chloride (table salt) is the most abundant
salt in the ocean
Factors increasing salinity include evaporation and
freezing; factors decreasing salinity include
precipitation and rivers
Most oxygen in oceans come from the atmosphere
because it is closer to the surface of the water.
The Salty Ocean
• Two gases found in the oceans are
necessary for living things: oxygen and
carbon dioxide
• Temperature decreases in the ocean with
depth
• Pressure increases with depth in the
ocean
• Scuba divers are prevented from
descending father than 40 m because of
pressure
Divisions of the Global Oceans
• Pacific- the largest ocean; getting smaller
• Atlantic- the second largest; getting larger
• Indian- third largest;
• Southern- located along the border of
Antarctica
• Artic- smallest ocean; most
oceanographers consider it as an
extension of the Pacific, Atlantic, and
Indian Oceans
How Did the Oceans Form?
• About 4 billion years ago, the Earth cooled
enough for water vapor to condense.
• The water began to fall as rain.
• The rain filled the deeper levels of Earth’s
surface and the first oceans began to
form.
Characteristics of Ocean Water
• Ocean water is salty
• Chock-full of solids
• Climate affects salinity
• Water movement affects salinity
• Temperate zones
• Surface temperature Changes
Ocean Water is Salty
• Most of the salt found in oceans is sodium
chloride (table salt).
• Salts have been added to the oceans for billions
•
of years by running waters (rivers, streams)
which dissolve various minerals, and then dump
the water into the oceans.
Also, solid materials come from volcanic
eruptions, hot springs, ocean waves crashing
against rocks
Chock-Full of Solids
• Salinity- the measure of the amount of
dissolved salts in a given amount of water.
• Measured in grams (g).
• 1 kg (1000 g) of ocean water carries an
average of 35 g of salt (3.5%).
• During the water cycle, fresh water from
the ocean is evaporated leaving only the
salts behind.
Climate Affects Salinity
• Some parts of the ocean are saltier than other
•
•
•
parts of the ocean.
Coastal waters in places with hotter, drier
climates have a higher salinity.
Coastal waters in places with cooler, more
humid climates have a lower salinity.
Main reason: evaporation
• Coastal waters have less salinity because more
fresh water from rivers run into the oceans in
these areas.
Water Movement Affects Salinity
• Some parts of the ocean (bays, seas,
gulfs) move less than other parts.
• Also, some parts of the open ocean that
do not have currents run through them
can be slow moving.
• Slower-moving areas of water develop
high salinity.
Temperate Zones
• Temperature of ocean water decreases
with depth.
• Water in the ocean is divided into three
layers by temperate.
• Top layer (surface zone)
• Middle layer (thermocline zone)
• Bottom layer (deep zone)
Temperature Changes
• Temperature in the surface zones vary
with latitude and the time of the year.
• Parts of the ocean along the equator are
warm because it receives more direct
sunlight per year than areas closer to the
poles.
Quick Check
Ocean water is more dense than freshwater
at the same temperature because of
A.
B.
C.
D.
pressure.
salinity.
the Coriolis effect.
upwelling.
Quick Check
The most common substances dissolved in
ocean water are
A.
B.
C.
D.
sodium and chloride.
potassium and chloride.
potassium and sodium.
calcium and chloride.
Quick Check
The concentration of all dissolved
substances in seawater is 3.5%. How
many grams of dissolved substances are
in 200 grams of saltwater?
A. 3.5
B. 7.0
C. 57
D. 200
Quick Check
What is the salinity of saltwater?
As you descend deeper into the ocean
temperature _____________ and pressure
__________.
The two sources of oxygen in ocean water
are __________ and __________.
Exploring the
Ocean
EQ: What are some
features of the ocean floor?
What factors make ocean floor
research difficult?
• Because of darkness, cold, and extreme
•
pressure, scientists had to develop new
technology to enable them to study the deep
ocean floor.
SONAR stands for sound navigation and
ranging.
• Oceanographers study the oceans by:
-sonar
-satellite
What are some of the features of
the ocean floor?
• The eight features of the ocean floor are:
– Continental shelf: a gentle sloping, shallow
area of the ocean floor that extends outward
from the edge of the continent.
– Continental slope: marks the true edge of a
continent, a steady slope where rock that
makes up the continent stops and the rock
that makes up the ocean floor begin.
– Seamounts: mountains completely under
water; extinct volcanoes
What are some of the features of
the ocean floor?
– Abyssal plain: smooth, flat region of the ocean floor
– Mid-ocean ridge: a continuous range of mountains
that wind around Earth’s ocean floor.
– Volcanic Island: very tall mountains created by the
cooling and hardening of erupting volcanoes on the
ocean floor.
– Deep-sea Trench: canyons on the ocean floor that are
the deepest spots on Earth.
– Guyot- flat-top mountain flattened by the action of
waves
– SONAR stands for sound navigation and ranging. It
is a system that uses sound waves to calculate the
distance to an object.
Quick Check
A smooth, nearly flat region of the ocean
floor is call a(n)
A. trench.
B. mid-ocean ridge.
C. abyssal plain.
D. sea mount.
Quick Check
Which ocean floor feature makes up the
deepest parts of the ocean?
A. abyssal plain
B. mid-ocean ridge.
C. deep-sea trench.
D. sea mount
Quick Check
What three (3) factors make ocean floor
research difficult?
1. _______
2. ______
3. ______
Quick Check
What are some features of the ocean floor?
1. __________
2. __________
3. __________
4. __________
5. __________
6. __________
Lesson 12
Waves, Currents,
and Tides
EQ: What causes the ocean to move?
Waves
• A wave is a disturbance that transfers energy
through matter or space.
• Wind transfers energy into the sea causing
waves to occur.
• Undersea earthquakes and landslides can also
put energy into the water to produce ocean
waves.
Waves
• The size of a wave depends on the amount of energy
that is transferred to the water.
• The amount of energy transferred depends on three
things:
– Wind speed
– Length of time it blows
– Distance over which it blows
• As each of these factors increase, so does the size of the
wave.
Ocean Currents
• Winds are responsible for ocean currents.
• A surface current is an ocean current that moves
along the top part of an ocean.
• Surface currents are moved by prevailing winds.
• Prevailing winds are winds that blow in regular
directions almost all the time.
Ocean Currents
• Surface currents can be cold or warm.
• Those that flow from the poles toward the
equator are cold.
• Those that flow from the equator towards the
poles is warm.
• The Gulf Stream is a warm current that flows
northward up the east coast of the United States
toward Great Britain and western Europe.
Tides
• A tide is the rise and fall of the ocean’s
surface caused mostly by the gravitational
pull of the moon.
• At high tide, the ocean water has risen as
high as it will go on a shore.
• At low tide, the ocean water has fallen as
low as it can go on a shore.
Tides
• Earth’s rotation on its axis affects which tides
will occur at a certain place on Earth.
• High tides occur about every 12 hrs.
• Low tides occur about every 12 hours.
• The time between low tide and high tide is
about 6 hrs.
Quick Check
What causes tides but NOY waves and
currents?
A. winds and the moon’s gravity
B. mostly the moon’s gravity
C. mostly the sun’s gravity
D. only winds
Quick Check
What is the main cause of the Gulf Stream?
A. storms
B. winds that blow now and then
C. winds that blow in regular directions
D. the moon’s gravity
Quick Check
If the first high tide of the day occurs at
1:00 a.m., the next high tide will come
closest to
A. 7:00 a.m.
B. 7:00 p.m.
C. 1:00 a.m. the next day
D. 1:00 p.m.
Quick Check
What is the cause waves and currents but
NOT tides?
A. wind
B. the moon’s gravity
C. the sun’s gravity
D. Earth’s gravity
Quick Check
What is the cause of most ocean waves?
A. The climate
B. The large ships in the ocean
C. The moon
D. The wind
Quick Check
A wave will increase in height when the
distance over which the wind blows over
the sea
A. increases.
B. decreases.
C. stays the same.
D is 0 kilometers.
Quick Check
The wave will increase in height when the
speed of the wind
A. remains unchanged for a long time.
B. decreases.
C. increases.
D. changes direction.
Quick Check
Which will produce the highest wave?
A. wind speed of 10 km/h
B. wind speed of 20 km/h
C. wind speed of 30 km/h
D. wind speed of 40 km/h
Quick Check
Which unit of measurement would you use
to express the area of the Atlantic Ocean?
A. m
B. km
C. m²
D. km²
Section 13 – 1
Wave Action
Wave Action
How does a wave form?
How does wavelength
and wave height
change as a wave
enters shallow water?
How do water particles
move within a wave?
How Waves Form
• Most waves form when winds blowing
across the water’s surface transmit their
energy to the water.
• Near shore, the wave height increases and
the wavelength decreases.
• As the energy in a wave passes, water
particles move in a circular path, ending in
their original position.
Describing Waves
• Crest – highest part of a wave
• Trough – lowest part of a wave
• Wavelength – horizontal distance between
crests or troughs
• Wave height – vertical distance from the
crest to the trough
• Frequency – number of waves that pass a
point in a certain amount of time
How Waves Change Near Shore
• In deep waters, waves travel as long, low
waves called swells.
• Near shore, the wave height increases and
the wavelength decreases.
• When the wave reaches a certain height,
the crest of the wave topples. The wave
breaks onto the shore, forming surf.
How Waves Affect the Shore
• Longshore Drift – movement of sand
along the beach
• Rip Currents – a rush of water that flows
rapidly back to sea through a narrow
opening
• Sandbar –as waves slow down, they
deposit the sand they are carrying on the
shallow, underwater slope in a long ridge
Reducing Beach Erosion
• Over time, erosion can wear away a beach
• Threatens homes, buildings, property
• groin – a wall of rocks or concrete to
reduce erosion along a stretch of beach
• Building groins can increases the amount
of erosion father down the beach
Quick Check
What is the cause of most ocean
waves?
A. The climate
B. The large ships in the ocean
C. The moon
D. The wind
Quick Check
Rolling waves with a large distance between
crests have a long
A. wave height
B. wavelength
C. frequency
D. trough
Quick Check
Groins are built to reduce the effect of
A. tsunamis.
B. longshore drift.
C. rip currents.
D. deep currents.
Quick Check
Sand is gradually carried down the beach by
A. groins
B. sandbars
C. crests
D. longshore drift
Section 13 - 4
Currents and Climate
EQ: What forces cause surface
currents and deep currents?
Surface Currents
• Surface currents are driven mainly by
winds and follow global wind patterns,
moving in circular patterns in ocean
basins.
• Surface currents affect water to a depth of
several hundred meters.
• Coriolis effect- the effect of Earth’s
rotation on the direction of winds and
currents
How Surface Currents Affect
Climate
• A surface current warms or cools the air
above it, influencing the climate of the
land near the coast.
• Climate is the pattern of temperature and
precipitation typical of an area over a long
period of time.
• Currents affect climate by moving cold
and warm water around the globe.
• Currents are large streams of moving
water that flow through the oceans
Deep Currents
• Deep currents are caused by differences
in density rather than surface winds.
• Cold waters at the bottom of the ocean
creep slowly across the ocean floor.
• Deep currents move and mix water around
the world.
• They move much slower than surface
currents.
Upwelling
• Upwelling is the upward movement of cold
water from the ocean depths.
• As wind blows away the warm surface
water, cold water rises to replace it.
• Upwelling brings up tiny ocean organisms,
minerals, and other nutrients from the
deeper layers of the water.
El Niño
• El Niño- an abnormal climate event that
occurs every 2 to 7 years in the Pacific
Ocean.
• This causes a sheet of warm water to
move eastward toward the South
American coast.
• El Niño can last for one to two years
before the usual winds and currents
return.
Quick Check
Winds and currents move in curved
paths because of
A.
B.
C.
D.
the Coriolis effect.
longshore drift.
wave height.
tides.
Quick Check
Currents are caused by
A. gravitational pull of the moon.
B. gravitational pull of the sun.
C. Winds, the earth’s rotation, and differences
in water density.
D. the earth’s rotation.
Quick Check
What causes tides but NOT waves and
currents?
A. winds and the moon’s gravity
B. mostly the moon’s gravity
C. mostly the sun’s gravity
D. only winds
Quick Check
What is the MAIN cause of the Gulf
Stream?
A. storms
B. winds that blow now and then
C. winds that blow in regular directions
D. the moon’s gravity
Section 13 - 2
Tides
EQ: What causes tides?
Tides
What causes tides?
How can tides be used to
generate electricity?
Describe the positions of the
sun and the moon, in
relation to Earth when
spring tides occur.
What causes tides?
• Tides are caused by the interaction of Earth, the
•
•
•
•
moon, and the sun.
The moon pulls on the water on the side closest
to it more strongly than it pulls on the center of
the Earth.
This pull creates a bulge of water, called a tidal
bulge, on the side of Earth facing the moon.
The water opposite the moon is pulled toward
the moon less strongly than the water facing the
moon.
This water is “left behind,” forming a second
bulge.
The Daily Tide Cycle
• As Earth turns completely around once each
•
day, people on or near the shore observe the
rise and fall of the tides as they reach the area
of each tidal bulge.
The high tides occur about 12 hrs. and 25 mins.
Apart in each location.
The Monthly Tide Cycle
• Changes in the positions of Earth, the moon, and the
•
•
•
•
•
sun affect the height of the tides during a month.
Twice a month, at he new moon and the full moon, the
sun and moon are in a straight line.
Their combined gravitational pull produces the greatest
range between high and low tide, called a spring tide.
In between spring tides, at the first and third quarters of
the month, the sun and moon pull at right angles to
each other, producing a neap tide.
A neap tide is a tide with the least difference between
low and high tide.
The movement of large amounts of water between high
and low tide are a source of potential energy—energy
that is stored and waiting to be used.
Quick Check
At the full moon, the combined gravitational
pulls of the sun and the moon produce a
A. surface current.
B. neap tide.
C. spring tide.
D. rip current.
Quick Check
A tide which water reaches its lowest point
on the beach each day is called
A. neap tide.
B. high tide.
C. spring tide.
D. low tide.
Quick Check
Tide with the least difference between high
and low tide is called
A. neap tide.
B. high tide.
C. spring tide.
D. low tide.
Quick Check
A tide in which water reaches its highest
point on the beach each day is called a
A. neap tide.
B. high tide.
C. spring tide.
D. low tide.
Quick Check
If the first high tide of the day occurs at
1:00 am, the next high tide will come
closest to
A. 7:00 am
B. 1:00 am the next day
C. 7:00 pm
D. 1:00 pm
Quick Check
Tide with the greatest difference between
high and low tide is called a
A. neap tide.
B. high tide.
C. spring tide.
D. low tide.
Quick Check
High tides occur
A. once every two days.
B. once a day.
C. twice a day.
D. four times a day.