The Water Cycle

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Let’s think….
Look at the background of this slide. What do
you see that has an affect on the water cycle or
is a part of the water cycle?
Write your answer down on your notes page.
Discuss with your shoulder partner.
Discuss with the class.
So what is the water cycle?
The water cycle is the movement of water
between the atmosphere, land, ocean, and even
living things.
Water on Earth
Water on earth can be found in three different
states
Liquid water
Ice
Water vapor
Water changes state as energy is absorbed or
released.
Movement of energy
When water absorbs energy from its surroundings it:
Melts from solid to liquid
Evaporates from liquid to gas
Sublimates from solid to gas
Think about the sun. we know energy in the form of heat is
transferred from an object of higher temperature to the
object with a lower temperature.
So think about a frozen pond. It absorbs the heat energy from
the suns radiation and melts from a solid to a liquid.
Movement of energy cont.
When water releases energy into its surroundings it:
Condenses from gas to liquid(clouds)
Freezes from liquid to solid
Deposits from gas to solid.
Think about a freezing day in the winter. Liquid water
will release all of its heat into the air. As this happens
the liquid water will change state to a solid.(ice)
What are the three states
of water?
Write the question and answer in your notes. We
will go over the question in just a minute.
Solid
Liquid
gas
Movement of energy cont.
Energy can also be transported by the
movement of water from place to place.
For example, water that evaporates from the ocean
carries energy into the atmosphere. This energy, if
the conditions are right, can generate hurricanes.
HOW DOES WATER MOVE?
Water moves in many ways.
Water moves from the ground to the atmosphere.
Water moves from the atmosphere to the ground.
Water moves across land.
From the ground to the atmosphere
Water reaches the atmosphere as water vapor in three
ways.
Evaporation – when liquid water changes into water vapor.
Most of the water in the atmosphere comes from the Earth’s
oceans, this is because oceans cover most of the earth.
Transpiration – the process by which plants release water
vapor into the air through stomata.
Sublimation – the process in which a solid chages directly
into a gas.
Let’s collect some water
In just a minute we are going to split into groups
and go conduct a lab on transpiration. Wait for
instructions. But first, who cat tell me what
transpiration is again?
Right! It is the release of water vapor from a
plants stomata into the air.
We will go set up our lab and then make
observations 5th period.
What happens to water in
the atmosphere?
Condensation
Precipitation
Cont.
Water vapor in the atmosphere mixes with other
gases. To leave the atmosphere water vapor
must change state to liquid water or solid water.
The change of state from a gas (water vapor) to
liquid water is called condensation.
Condensation occurs if the air that contains water
vapor is cooled enough. The vapor condenses on
smaller particles such as dust to form clouds, fog and
mist.
What happens in clouds
In clouds, water droplets may collide and stick
together to become larger. If a droplet becomes
large enough, it falls to earth’s surface as
precipitation.
examples of precipitation are hail, rain, and snow.
The movement of water on
land and in oceans.
After water falls to earth in flows and circulates all
over Earth.
On land liquid water flows downhill both on the
surface and underground.
Water that flows downhill over land is called runoff.
As this water is flowing downhill some seeps into the
ground in a process called infiltration.
Water that makes it underground moves downhill
underground as groundwater.
Cont.
Solid water such as glaciers also move slowly
downhill due to gravity.
In oceans, winds move ocean water on the
surface this is called surface currents.
Deep ocean currents are formed by colder water
sinking and forcing other water out of its space.
Write 2 ways water moves
on land.
Example answers
Runoff
Infiltration
Groundwater
Ice flow
Ocean currents
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