Chapter 24.3 Weather Instruments

Objectives Describe the types of instruments used to measure air temperature and wind speed Describe the types of instruments used to measure air temperature and wind speed Describe the instruments used to measure upper atmospheric weather conditions. Describe the instruments used to measure upper atmospheric weather conditions.

Measuring Air Temperature Thermometer: used to measure temperature. Thermometer: used to measure temperature. This type of thermometer is a liquid thermometer This type of thermometer is a liquid thermometer Fahrenheit and Celsius are the two temperature scales commonly used in the United States. Fahrenheit and Celsius are the two temperature scales commonly used in the United States.

Satellite images made by using infrared energy reveal information about atmospheric temperature.

Measuring Wind Anemometer: Instrument Anemometer: Instrument scientist use to measure wind speed. Wind Vane: Is used to determine the direction of the wind. Wind Vane: Is used to determine the direction of the wind. –Is shaped like an arrow with a tail. –If a weather vain points North on a very windy day. The wind is described as “Northerly”.

Winds Continued… Scientists gather information about wind speed and direction by tracking a helium- filled balloon. Scientists gather information about wind speed and direction by tracking a helium- filled balloon. When a weather map shows a wind symbol at 270 o, it indicates that the wind is coming from the west. When a weather map shows a wind symbol at 270 o, it indicates that the wind is coming from the west. North is 0 o, East is 90 o, South is 180 o North is 0 o, East is 90 o, South is 180 o

Measuring Upper-Atmospheric Conditions Barometer: Used to measure air pressure. Barometer: Used to measure air pressure. Radiosondes: used most often to measure relative humidity. Radiosondes: used most often to measure relative humidity.

Weather Satellites Satellites take pictures of direction and speed of clouds Satellites take pictures of direction and speed of clouds This allows scientists to predict where the storms might be heading This allows scientists to predict where the storms might be heading Satellites can also measure marine conditions- ocean temp, ocean currents, etc. Satellites can also measure marine conditions- ocean temp, ocean currents, etc.