Chapter 2 OBSERVING WEATHER

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Chapter 2 OBSERVING WEATHER

• AIR PRESSURE
• The push of the air in all directions against its
  surroundings.
• BAROMETER
• A device used to measure air pressure.
• HIGH PRESSURE AREAS
• An area of higher air pressure than that of the
  surrounding air.
• LOW PRESSURE AREAS
• An area of lower air pressure than that of the
  surrounding air.
• WIND VANE
• A device, often shaped like an arrow, used to
  show the direction of the wind.

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• WINDSOCK
• A device used to show wind direction, consisting
  of a cloth bag that is open at both ends and hung
  on a pole.
• ANEMOMETER
• A device used to measure the speed of the wind.
• HUMIDITY
• The amount of water vapor in the air.
• RELATIVE HUMIDITY
• The amount of water vapor present in the air at a
  given temperature compared to the maximum amount
  that the air could hold at that temperature.
• EVAPORATE
• To change from liquid to a gas.

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• CONDENSES
• To change from a gas to a liquid.
• CLOUD
• A mass of tiny droplets of water that condensed
  from the air.
• PRECIPITATION
• Any form of water that falls from clouds to
  Earths surface.
• RAIN GAUGE
• A device for measuring precipitation.