Slide 2 / / / Mr. Harpers science mini- lesson with read-along
audio Click on the speaker icons to hear the spoken words Slide 3
All water is made of tiny, tiny particles called molecules, way too
small to see. several ways to draw water molecules Slide 4 When
these molecules get cold they slow down and freeze solid. Frozen
water is called ice and can be like rock. Slide 5 The molecules in
any solid substance are stuck together. Slide 6 Solid things do not
easily change shape or size. Slide 7 If ice gets warmer it melts
and becomes liquid. The molecules move faster and begin to slip and
slide past each other. Slide 8 The molecules in a liquid substance
can slide by each other and change shape. Slide 9 This is why
liquid water changes shape so easily and can go through small
places. Slide 10 As liquid water gets warmer the molecules begin to
float up and away from the liquid and become gas (part of the air).
Slide 11 The molecules in a gas substance float and stay apart from
each other. Slide 12 Water molecules in the air are called vapor.
The process when liquid water changes into vapor is called
evaporation. Slide 13 Evaporation is what happens when water in an
open container seems to disappear after a few days. Slide 14 The
more water is heated, the faster evaporation happens. Slide 15 When
the temperature gets hotter, evaporation happens faster. Thats why
a wet sidewalk gets dry quickly when the sun comes out. Heat is
what makes water evaporate. Slide 16 We cant see water vapor in the
air because its invisible, but its always there as part of the air
around us. Slide 17 About 75% of Earths surface is covered by ocean
water. Slide 18 / / / / Every day as the sun warms the oceans, many
tons of water molecules evaporate and become gas vapor in the
atmosphere. Heat is what makes water evaporate. Slide 19 Water
vapor high in the sky can cool and condense into tiny floating
droplets of liquid water. Large groups of liquid droplets are what
clouds are made of. Slide 20 The clouds and vapor are blown by
winds all over Earth. Some of it moves over land. Slide 21 When
clouds get colder the droplets get bigger. This makes the clouds
look darker. Slide 22 When the droplets in clouds get too big and
heavy to float they fall to the ground as rain. Slide 23 Some of
the rain that falls soaks into the soil to give water to the trees
and plants. Slide 24 Some rain water seeps deep underground and
collects as groundwater that people can get when they dig a well.
Slide 25 / When it gets really cold, rain turns into snow.
Sometimes snow and ice can lay on the ground for a long time. Slide
26 Rain that doesnt soak into the ground, or freeze into ice and
snow will run down hill toward the ocean. Slide 27 Streams flow
together and get bigger as they move toward the ocean. Slide 28
This runoff water keeps moving downhill until it flows into the
ocean. Slide 29 Slide 30 The sun warms the ocean and the water
cycle keeps going, just like it has for billions of years. Slide 31
Every water molecule on Earth has gone around this Water Cycle
many, many times in the past. vapor Slide 32 If you are a 4 th of 5
th grader, or a younger student who really likes science, this
program continues. Just keep clicking. Slide 33 There are four
steps of the Water Cycle that we should all know. evaporation
condensation precipitation runoff Slide 34 Evaporation is when
liquid water that has been warmed by the sun evaporates and becomes
vapor, a gas in the air. evaporation condensation precipitation
runoff Slide 35 Condensation Slide 36 You can see condensation on a
cold soda can when the air near the can gets cool and the vapor in
that air turns to liquid. Slide 37 When clouds get cooler, the
droplets condense into bigger drops. When the condensation gets too
heavy to float, it will fall to the ground. Slide 38 Precipitation
is when water falls from the sky. If it is warm enough to be
liquid, we call it rain. Slide 39 When the air is colder the
precipitation freezes and becomes snow. Slide 40 Sometimes cold
precipitation falls as beads of ice called sleet. Slide 41
Sometimes precipitation gets blown by updrafts up high where the
air is very cold. Balls of ice get bigger as the wind pushes them
up. Slide 42 When the ice balls fall they are called hail. Big hail
stones can be very dangerous. Slide 43 is the water that runs
downhill. Sooner or later the ice and snow melt. Any precipitation
water that doesnt soak into the ground or get used by plants and
animals runs downhill toward the ocean as runoff. Runoff Slide 44
Runoff streams join together until they form huge rivers that flow
into the ocean. Slide 45 The Water Cycle keeps going around and
around. The cycle never stops. Slide 46 By the time you are a 5 th
grader, you should know the four steps of the Water Cycle. Slide 47
1.Evaporation 2.Condensation 3.Precipitation 4.Runoff Liquid water
becomes part of the air By the time you are a 5 th grader, you
should know the four steps of the Water Cycle. Slide 48
1.Evaporation 2.Condensation 3.Precipitation 4.Runoff Water vapor
cools and becomes liquid. By the time you are a 5 th grader, you
should know the four steps of the Water Cycle. Slide 49
1.Evaporation 2.Condensation 3.Precipitation 4.Runoff Water
droplets get heavy and fall. Rain, snow, sleet. hail By the time
you are a 5 th grader, you should know the four steps of the Water
Cycle. Slide 50 1.Evaporation 2.Condensation 3.Precipitation
4.Runoff Water flows back to the ocean. Slide 51 Wow, you just
learned a lot about The Water Cycle! You must really be interested
in science. But if you want even more science just keep on clicking
that mouse Slide 52 / All living things on Earth must have water to
live. Slide 53 Some plants and animals only need a little water to
survive. Slide 54 Other plants and animals need a lot of water in
order to survive. Slide 55 Earth has a lot of water, but almost all
(97%) of Earths water is salty ocean water. Slide 56 This is fine
for plants and animals that live in the sea. Salt water is OK for
them. Slide 57 But people cant drink saltwater. People must have
fresh water with no salt in it. All plants and animals that live on
land need fresh water to live. Slide 58 People cant drink salty
ocean water. The plants we need for food cant live with salty
water. Animals on land need a lot of fresh water with no salt in
it. Slide 59 Salt water wont kill you if you get a little bit in
your mouth at the beach. But if all you had to drink was ocean
water you would get very sick and be dead in just a few days. Slide
60 If most of Earths water is salt water, where can we get enough
fresh water to live? Slide 61 Lucky for us, when salt water
evaporates only the fresh water molecules become water vapor. All
the salt stays behind in the ocean. Slide 62 When the suns heat
evaporates ocean water only the fresh water molecules become vapor
that forms into clouds. Slide 63 That means that all the water in
clouds is fresh water. And all the water in rain is fresh water.
And all the water in the soil and underground is fresh water. And
all the water in streams, lakes, and rivers is fresh water. Slide
64 So theres plenty of fresh water, right? Slide 65 Not really,
There are 7 billion people on this planet that all need fresh
water. If everybody wastes fresh water there might not be enough.
Slide 66 But there are things we can do to help conserve our
important water resources. Slide 67 Dont let the water run while
you brush your teeth. We only really need a little bit to wet the
brush, then at the end to rinse our mouth and the toothbrush. Slide
68 Dont take super long showers. Its important to stay clean, but
some people waste a lot of water when they shower. Slide 69 Please
dont waste water.
