Meteorology
Notes #3
Subject: V. Meteorology – the study of the Atmosphere and Weather
Main Ideas
A. Properties of Air
Details
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Some very important properties of air include: mass, volume,
pressure, and density.
Air consists of (is made of) tiny invisible gases called molecules.
1. Mass
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The measurement of the amount of matter an object contains.
Air does have mass!
Those tiny molecules do have mass!
2. Volume
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The amount of space an object takes up.
Air does have volume! It does take up space.
Even though it is invisible those tiny molecule do take up the space
in front of you.
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A force on a surface by an object.
Gravity causes everything, including air, to be pushed down,
causing pressure.
Because air has mass, gravity pushes down on the air, causing
pressure.
3. Pressure – 2 types
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a. High Pressure
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An area where air pressure is strong
Air pressure is high closest to the surface of the Earth.
b. Low Pressure
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An area where air pressure is weak
Air pressure decreases the higher you go in the atmosphere.
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The amount of matter in a given amount of space
The density of air is affected by the temperature of the air.
Remember air with different densities form layers.
The least dense is on top.
The densest is on the bottom.
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Hot air expands.
It, therefore, becomes less dense.
Hot air rises
Low Pressure (L)
4. Density
a. Hot/warm Air
b. Cold/cool Air
Summary:
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Cold air shrinks
It, therefore, becomes more dense.
Cold air sinks!
High Pressure (H)