Air is an invisible mixture of gases that surrounds us, mainly consisting of oxygen and nitrogen. It has no smell, taste or color like water. Wind is moving air caused by differences in temperature, with hot air rising and cold air sinking, which causes clouds and breezes to move. Different wind speeds have names, from light breezes that move leaves to strong gales that can damage trees, and very powerful hurricanes that can destroy buildings. Instruments like anemometers and weather vanes are used to measure wind speed and direction.

2. Air is all around us
and we can’t see it.
Air is a mixture of
gases, but it consists
mainly of oxygen
and nitrogen.

3. Air and water have the same
characteristics;
they have no smell, no taste and no colour.

4. Wind is moving air.
Hot air goes up
and
cold air goes down.

5. The difference in air
temperature causes wind,
which moves air from one
place to another.
This is why clouds move.

6. A little wind is
called a breeze.
A breeze moves
the leaves on the
trees. It can help
us feel cooler on
a hot day.
There are different types of wind.
When there is no wind or we can’t feel it we say it is
calm.

7. A gale is a strong
wind.
A gale moves the
branches on trees
and can
sometimes blow
trees down.
A hurricane is a very
strong wind. A
hurricane can destroy
houses and other
buildings.

8. We can measure how fast the
wind is moving with an
anemometer.
We can find out the direction the
wind is blowing with a weather
vane.