Download SP4-Unit A-C02-v3

apter 2
Ch
Using Clouds
to Predict Weather
Before you read, scan
the section and notice
the highlighted words.
What three types of
clouds will you learn
about?
Take a look at the sky. You will probably see some clouds.
Clouds cover about half of Earth at any given time. Clouds
are one of the best ways to predict what the weather will be
like for the next little while.
Clouds are grouped by the way they look. There are only
three main types of clouds, so it is easy to recognize them. You
might see more than one type of cloud in the sky at one time.
Cumulus clouds [KYOOM-yuh-luhs kloudz] are fluffy-
looking clouds. They are often tall clouds, piled high and
puffy, like cotton puffs stacked together but with flat bottoms.
Sometimes cumulus clouds are big and close to the ground,
and sometimes they are high up in the air and look very tiny.
Cumulus clouds usually mean that there will be fair weather.
However, if they are very tall and have dark bottoms, they
may bring thunderstorms.
왖 Cumulus clouds
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NEL
Cirrus clouds [SEAR-uhs kloudz] are thin, feather-like
clouds that can look like hair. They show the direction the
wind is blowing. They are always very high in the sky and
are made up of ice crystals. They can mean that there will
be no precipitation now, but that a low pressure air mass is
approaching. The low pressure air mass might bring rain
or snow.
왖 Cirrus clouds
Stratus clouds are flat, layered clouds. They often block
the Sun and cause a dull, grey day or bring rainy weather.
Fog is a stratus cloud at ground level.
왖 Stratus clouds
NEL
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Close your eyes and
try to “see” the type
of cloud that would
bring rain.
The colour of a cloud tells you how much water is in it.
Very white clouds have little moisture. Very dark clouds have
lots of moisture and will probably bring rain.
Start looking at clouds and you may begin to see some
patterns. If you see dark stratus clouds coming, take an
umbrella to school! If you see a few cumulus clouds in the
sky, you can enjoy fair weather. If there are cirrus clouds in
the sky, it may rain or snow tomorrow or the day after. You
can even see clouds changing through the day. Look at the
sky before school, and look at it again at different times
during the day to see if there are any changes.
1. Record the types of clouds you see over the next five days. Do
this twice a day, once in the morning and once in the afternoon.
Choose the same times each day.
Day
Day 1
Type of Morning:
Cloud
cumulus
Day 2
Day 3
Day 4
Morning:
Morning:
Morning:
Afternoon: Afternoon: Afternoon: Afternoon:
2. Draw and label the three main types of clouds—cumulus, cirrus,
and stratus.
3. What can each type of cloud tell you about the weather?
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NEL