Water in Earth’s Processes
Study Guide
Our test will be
December 17, 18, or 19,
depending on your class period.
“The Blue Planet”
70% of the Earth’s
surface is covered
in water.
97% of the water on Earth is salt water.
The oceans’ salinity is too high for humans to consume.
 The salt in the ocean and seas comes from weathering
and erosion of rocks.
 Sea water has a higher concentration of sodium
chloride, NaCl (salt).
 When fresh water pours into the ocean, the salinity
(salt content) stays the same because water continually
evaporates out of the ocean.
3% of the water on Earth is fresh water.
Ice caps and glaciers make up 2%.
The greatest amount of
fresh water on Earth is
found in glaciers and polar
ice caps.
Groundwater makes up .9%.
Rivers, lakes, and swamps make up .1%.
Lake Superior
Largest freshwater body on Earth
Amazon River
Largest carrier of freshwater to the ocean
If new wells are created due to a population
increase, the water table would drop.
Threats to Our Water Supply
1. Pollution – fertilizers, pesticides, sediments, trash, oil/gasoline,
chemicals pollute groundwater
2. Drought – long periods of little or no rain can affect water
supply and farming
3. Overuse- humans are consuming too much of freshwater
supply
HUMANS ARE USING TOO MUCH WATER.
*The average person uses between 40 to 80 gallons of
water per day.
*An average family of 4 uses between 160 to 320 gallons of
water per day.
The Water Cycle
 The water cycle is powered by heat from the Sun. It is the
continuous movement of water from the ocean to the
atmosphere to the land and back to the ocean.
Check out the difference between Earth and the sun!
Heat energy from the sun causes evaporation
and transpiration.
 Evaporation is when liquid water changes into water
vapor and rises.
Evaporation
http://www.middleschoolchemistry.com/multimedia/chapter2/lesson2
See what water molecules are doing during evaporation.
Transpiration
Transpiration is evaporation
of water through plant leaves.
If you were to hang a wet swimsuit
to dry, the heat of the sun, the speed
of the wind, and the amount of water
vapor in the air (humidity) would
affect the evaporation/dry time.
Air always contains some water vapor through
evaporation. We become more aware of water vapor
when air is humid.
Condensation
Condensation is when
water vapor cools and
changes into water
droplets that cling to
dust particles and form
clouds in the atmosphere.
Condensation
Condensation
See what water molecules are doing during condensation.
http://www.middleschoolchemistry.com/multimedia/chapter2
/lesson3
Precipitation
Precipitation is rain,
snow, sleet, or hail
that falls from
clouds onto the
Earth’s land and
oceans.
Types of Frozen Precipitation
(determined by air temperature)
1. Snow- water vapor turns directly to a solid
2. Sleet- rain drops pass through a layer of freezing
temperature near Earth’s surface
3. Hail- water droplets freeze around a small ice crystal
Snow
Hail
Sleet
Where does precipitation go?
 Percolation is the downward movement of water
through pores and other spaces in soil due to gravity.
 Runoff is precipitation that flows over land into
streams and rivers.
 Accumulation is when water gathers in large
quantities such as rivers, lakes, oceans, glaciers, ice
caps, and aquifers (geological formation containing
groundwater.)
Water Cycle Song
https://www.youtube.com/watch?v=o3BVa7PH_JE&list=
UUJjstNDkwktHyvUdtcBfb2g&safe=active
Ocean Motion
3
Currents
types
Waves
“Rivers in oceans”
Tides
2 types
Surface
Currents
Deep
Currents
Caused by
Caused by
Winds
blowing
constantly
Changes in
temperature
and salinity
upwelling
Winds
blowing
occasionally
Caused by
Moon’s
gravitational
pull on Earth
Waves
 Waves are mostly caused by wind, which is caused by
energy from the Sun.
Parts of a wave:
Crest: The highest point of the wave
Trough: The lowest point of the wave
Wave length: distance from crest to crest
(or trough to trough)
Wave height: distance from trough to crest
In a wave, water molecules move in a
circle. ONLY the energy moves forward.
Think about how floating objects move in deep ocean
water. Do they move forward? Or do they simply bob
up and down?
http://www.pbs.org/wnet/nature/conditionblack/seas_fl
ash.html
So that’s why the waves I play in near the
shore look different…
Sometimes undersea earthquakes or
landslides can cause waves.
http://www.embc.gov.bc.ca/em/tsunamis/causes_2.htm
Tsunami animation
Currents
 A current is a movement of ocean water that forms a regular
pattern.
Currents
 There are two types of currents: surface currents and
deep currents.
 Currents can best be described as “rivers in the
ocean.”
Just keep swimming!
http://www.youtube.com/watch?v=JpV7NIJTxD0
Surface Currents
 Surface currents are horizontal and occur within the
top several hundred meters of the ocean.
 Surface ocean currents
are caused by global winds,
the Coriolis Effect, and
continental deflections.
Global winds cause surface currents.
 Global winds are
constant and unchanging.
They are NOT the same as
local winds that
change daily.
Examine global surface currents.
The Coriolis Effect steers surface currents.
 Observe an animation of the Coriolis effect over
Earth's surface.
 Paper and pencil demonstration
Continental deflections steer surface currents.
 When a current runs into a continent, what does it
have to do? It has to deflect, or go a different way.
Surface currents affect climate.
How do you think the
Gulf Stream affects
the United Kingdom’s
climate?
Look at Hopedale in Canada
and Stornaway in Scotland,
each at about the same
distance from the Equator.
Which has a colder climate?
Why?
Surface currents affect climate.
 Columbia, SC sits at 34 degrees latitude
on the East Coast. Los Angeles, CA sits
at 34 degrees latitude on the West
coast. The average June temperature
for Columbia is 92 degrees. The average
June temperature for Los Angeles is 78
degrees. Look at the two cities on a
currents map. Can you figure out why?
Deep Currents
(also known as density currents)
 Density differences due to salinity and temperature
create deep currents, but not ocean waves.
Currents are pretty cool.
http://www.youtube.com/watch?v=JQZ3QkaWWqA
Density of Water
Think about those molecules.
 More salt (higher salinity), more dense water, sinks
 Less salt (lower salinity), less dense water, rises
Cooler water, more dense
Sinks!
Warmer water, less dense
Rises!
Coastal Upwelling
• An upwelling is a
circulation that brings
deep cold water to the
surface. It brings food
particles and nutrients
to the surface, and the
fish follow. Fishermen
love it!
Observe how upwelling
occurs.
Global Areas of Upwelling
Relating Cause and Effect
Cause
Effect
Global Winds
Surface currents
Differences in ocean
water density due to
salinity and temperature
Deep currents
Great Ocean Conveyor Belt
Currents and Nikes
On May 27, 1990 the freighter Hansa Carrier, heading to the U.S.
from Korea, encountered a severe North Pacific storm. During
the storm, a large wave washed twenty-one shipping containers
overboard. Five of these containers held a shipment of
approximately 80,000 Nike shoes that were released into the
North Pacific. Here is where they landed, years later:
Currents carry anything!
There’s a floating island of
STUFF sitting in the middle of
the Pacific, with everything
from plastic bags to entire
sections of a ship.
Ocean Currents
Surface Currents
Deep Currents
(Density Currents)
Directions: On the chart you made, write each sentence
below in the surface category or density category.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Powered by wind
Slow moving
Moves only the upper few hundred meters of water
Can cause upwelling
Created by changes in salinity or temperature.
Moves water horizontally, parallel to surface
Direction of movement is affected by Coriolis effect
Powered by differences in density
Transfers heat to the atmosphere which influences climate
Moves deep in the ocean
Tides
 Tides are the daily rise and fall of water levels that are
caused by gravity due to the moon and sun. Water
rises slowly and covers the shore twice a day then
slowly falls back.
Animation:
http://oceanservice.noaa.gov/education/tutorial_tides/
media/supp_tide05.html
High Tide
Low Tide
Spring Tide and Neap Tide
 High spring tides are caused by an alignment of the Earth, moon,
and sun.
 Neap tides have the smallest daily tidal change and occur when
the sun and moon are at right angles relative to the Earth. The
gravitational forces of the sun and moon work against each
other.
Animation:
http://oceanservice.noaa.gov/education/kits/tides/media/sup
p_tide06a.html
Spring and Neap Tides
Spring and Neap Tides Song
http://www.youtube.com/watch?v=KFYf_it461s&list=UU
JjstNDkwktHyvUdtcBfb2g
Ocean Topography Review
Draw and label the parts of the ocean floor.
Continental Shelf
Abyssal
Plain
Seamount
(Island if
above sea
level)
Mid-Ocean
Ridge
Continental Slope
Rift
Valley
Deep-sea
Trench
Ocean Topography Review
Match the number to the topographical feature.
1. Steeply sloping edge of continental shelf that drops to the
ocean basin
2. Volcano that does NOT rise above sea level
3. Mountain that rises ABOVE sea level
4. Relatively flat part of continent covered by sea water
5. Deepest part of the ocean, a deep ocean trough
6. Flat, almost level, area of the ocean basin, covered with
layers of sediments
7. Underwater mountain chain where 2 plates diverge
8. A break in the Earth’s crust where 2 plates diverge.
Ocean Topography Review
 Sonar is used to measure the depth of the ocean
floor.
 As you go deeper into the ocean, the pressure
increases; therefore, the pressure would be the
greatest in a trench.
 Algae is found above the continental shelf since it
needs sunlight to survive.
 Mid-ocean ridges are underwater mountain chains
near active volcanoes.
Remember those mid-ocean ridges?
https://www.youtube.com/watch?v=sgDM6m0lUGY&list=PLK5QnX_5Gp3Wfz4pMZ
OVMLd9ujDIzfAGb&index=1
Like the seams
of a baseball…
Resources and Energy
 Recycling – reusing waste or
scrap materials to help people
save natural resources.
 One renewable resource from
the ocean is wave energy.
Hydroelectric Energy
Hydroelectric energy is
energy created by the
movement of falling
water.