Weather Instruments

Meteorologists use instruments to measure the properties of air. Air has Temperature Precipitation Humidity Pressure Wind

Barometer Scientists use barometers to measure air pressure. The mass of air pressing down on us is 14.7 pounds/square inch When air pressure is high, the day is clear. Low air pressure means bad weather.

Aneroid Barometer Cell volume gets smaller as pressure increases Most common for home use

How do these barometers work?

72 Hour Barometer (inches)

Isobars (lines of constant pressure) on an air pressure map.

Psychrometer To measure relative humidity scientists use a psychrometer. There are digital and sling psychrometers. Psychrometers and hygrometers measure relative humidity and dew point. http://www.wildwildweather.com/humidity.htm

The number where the two measurements connect is the relative humidity. It is read in terms of %.

Thermometer Thermometers are used to measure temperature. Temperature is measured in degrees. The scale used is Celsius or Farenheit.

Types of Thermometers

Anemometer An anemometer is used to measure wind speed Air speed scale is written in miles/hour. Anemometer

How do these anemometers work?

Wind Vane The wind vane tells the direction the wind is coming from. Direction is read N, S, E, W, NE, NW, SE, SW. Wind speed and direction are usually read together.

Rain Gauge The amount of rain is measured in inches.

Doppler Radar http://www.wildwildweather.com/radar.htm

NEXRAD New and improved Doppler radar system NEXRAD (acronym) for NEXt generation RADar Can “see” into thunderstorms to determine rain drops and wind rotation for possible tornado.

Weather Stations http://www.nsf.gov/od/lpa/news/02/pr0212images.htm

The meteorologist brings it all together.

Show What You Know!

1. Name the instrument, what it measures, and its scale.

2. Name the instrument,property measured, and scale.

3. Name the instrument,property measured, and scale.

4. Name the instrument,property measured, and scale.

5. Name the instrument,property measured, and scale.

6. Name the instrument,property measured, and scale.

1. Name the instrument, what it measures, and its scale. Barometer Air pressure Isobars

2. Name the instrument,property measured, and scale. Wind vane Wind direction North, south, east, west, NE,NW.SE,SW

3. Name the instrument,property measured, and scale. Hygrometer or psychrometer Humidity %

4. Name the instrument,property measured, and scale. Anemometer Wind speed Miles/hour

5. Name the instrument,property measured, and scale. Rain gauge Precipitation Inches

6. Name the instrument,property measured, and scale. Thermometer Air temperature Degrees Celsius or Fahrenheit

7. Instrument, measuring? Doppler Storm data

What kind of meteorologist are you?

Resources http://www.wildwildweather.com/radar.htm http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/cld/cldtyp/home.rxml http://www.usatoday.com/weather/wfog.htm http://www.google.com/