The clear plastic precipitation chamber should
be removed from the cube and placed in an
open area away from any overhead obstruc-
tions.
You can check the gauge at the end of each
day. The chamber will measure rain and snow.
One interesting fact is that snow has ten times
the volume of rain, so if ten inches (25.4 cm)
of snow falls, it is the equivalent of just one
inch (2.54 cm) of rain.
4. Cube Placement
The cubes in your set have been made so that
they can be moved and joined together in va-
rious combinations. You might want to place
the different cubes in different places, or try
them all together in one place.
Please note, cube 1, the anemometer and
wind vane, must always be at the top, as the
wind cups need freedom to rotate and cannot
be blocked by obstructions.
5. The Weather
Climate
The Climate is often spoken about at the
same time as weather, but is something quite
different. The climate is the common, average
weather conditions at a particular place over
a long period of time (for example, more than
30 years). We learn about different climates
around the world. Deserts have a hot and dry
climate while the Antarctic has a very cold and
dry climate.
Atmosphere
The atmosphere is needed to sustain life and
vital to living organisms It is a gaseous envelo-
pe of air that surrounds the earth. The atmos-
phere of the earth is about 1.000 to 3.000
km thick and consists of a mixture of gases.
The atmosphere is bound by the gravitational
fi eld of the earth.
Wind
Wind is air in motion. It is produced by the
uneven heating of the earth's surface by the
sun. Since the earth's surface is made of va-
rious land and water formations, it absorbs the
sun's radiation unevenly. Two factors are ne-
cessary to measure wind: speed and direction.
As the sun warms the earth's surface, the
atmosphere warms too. Some parts of the
earth receive direct rays from the sun all year
and are always warm. Other places receive
indirect rays, so the climate is colder. Warm
air, which is lighter than cold air, rises. Cool
air moves in and replaces the rising warm air.
This movement of air is what makes the wind
blow.
Rain
Water droplets form from warm air. As the
warm air rises in the sky it cools. Water va-
pour (invisible water in the air) always exists
in our air. Warm air holds quite a bit of water.
For example, in the summer it is usually very
humid. When enough of these droplets coll-
ect together, we see them as clouds. If the
clouds are big enough and have enough wa-
ter droplets, the droplets bang together and
form even bigger drops. When the drops get
heavy, they fall because of gravity, and you
see and feel rain.
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