Ciencias Naturales

2. What Are Clouds?
Sadly, clouds are not made up of candy floss or cotton wool and
unfortunately you can’t bounce on them!
Clouds are actually made up of tiny droplets of water.
In the highest clouds, these tiny droplets change to ice crystals.

3. What Clouds Tell Us
Different types of clouds tell us different things about the weather.
We are going to look at the following categories:
• Cirrus
• Cumulus
• Stratus
• Nimbus

4. Cirrus
Cirrus clouds are the highest form of cloud.
They look like paint brush strokes across the sky.
They are made up of ice crystals and are above 18 000 feet.
They are normally white and predict pleasant weather.
Photo courtesy of linznix (@flickr.com) - granted under creative commons licence – attribution

5. Cumulus
Cumulus literally means a heap or pile.
Cumulus clouds are known as fair-weather clouds. They are fluffy and
tend to be seen on a sunny day.
Most forms of cumulus clouds will not produce any rain or snow.
Larger forms can produce some rain showers but these tend not to be
heavy.
Photo courtesy of Tez Goodyer (@flickr.com) - granted under creative commons licence – attribution

6. Stratus
These are the most common form of clouds in Britain. They are low layers
of clouds and tend to act as a block to the sun. They are found up to 6500
feet from the ground.
They can be any shade from white to dark grey.
They often mean rain!
Photo courtesy of whatStefanSees (@flickr.com) - granted under creative commons licence – attribution

7. Nimbus
Nimbus is a word which can be added to the other types of clouds e.g.
cumulonimbus.
Nimbus are clouds which bring us snow and rain.
Photo courtesy of katerha (@flickr.com) - granted under creative commons licence – attribution

8. Cumulonimbus
Cumulonimbus are storm clouds. They can reach enormous sizes. The rain
they produce comes suddenly and dramatically.
They can also produce snow or hailstones and cause thunder and lightning
storms. In other countries, they can even cause tornadoes.
Photo courtesy of berniedup (@flickr.com) - granted under creative commons licence – attribution

9. Quiz
1. Which type of cloud is the lowest lying?
2. What is name of the highest type of cloud?
3. Which type of cloud means there is a storm coming?
4. What are clouds made up of?
5. What do cirrus clouds look like?

10. Quiz - Answers
1. Which type of cloud is the lowest lying?
• Stratus
2. What is name of the highest type of cloud?
• Cirrus
3. Which type of cloud means there is a storm coming?
• Cumulonimbus
4. What are clouds made up of?
• Clouds are made up of tiny droplets of water. In
the higher forms of clouds the drops can change
to ice crystals.
5. What do cirrus clouds look like?
• They look like paint brush strokes in the sky.