Lesson 3 Page 1
Building Devices to Measure the
Weather
Instruments can be used to collect weather data.
If you want to do a good job of measuring the weather, you need to take a few important measurements. Click here for a brief overview video called Measuring the weather.
Wind Speed An anomemeter spins fast in high winds. |
Knowing how strong the wind is can tell how fast weather systems are changing. Wind speed is measured with an anemometer. An anemometer has several cups that stick out from a pole. The anemometer spins fast in high winds. The number of times the cups rotate in a period of time, allows scientists to tell how fast the wind is blowing. |
Wind Direction A weather vane points in the direction of the wind. |
Knowing the direction of the wind tells you in what direction weather systems are moving. Wind direction is measured with a weather vane or airport windsock. The weather vane or windsock points in the direction of the wind. |
Air Pressure A barometer reads air pressure. |
Air and weather systems flow from areas of high pressure to areas of low pressure. Air pressure is measured with a barometer. The higher the air pressure, the higher the reading on the barometer. A barometer lets you know when a cold or warm air mass is coming. Cold air creates more air pressure than warm air. As cold air comes, the barometer goes up. As warm air comes, the barometer goes down. |
Rainfall A rain gauge measures rainfall. |
Knowing the amount of rain helps people deal with and prepare for the amount of water that has fallen. Rainfall is measured with a rain gauge. The more water in the rain gauge, the greater the amount of rainfall. |
Snowfall A snow gauge measures snowfall. |
Knowing the amount of snow helps people deal with and prepare for the amount of snow that has fallen. Snowfall is measured with a snow gauge. The more snow in the snow gauge, the greater the amount of snowfall. |
Temperature A thermometer measures temperature. |
Temperature is probably the most important weather measurement. People need to prepare for hot or cold conditions. Temperature is measured with a thermometer. The warmer the temperature, the higher the reading on the thermometer. |
You can also get weather data from high in the atmosphere by sending up a weather balloon. Certain instruments, such as barometers and thermometers, are attached to a balloon. As they travel upward, a radio signal sends information about pressure and
temperature back to Earth. Also, the radio signal sends the position of the balloon, which tells you how fast the wind is blowing, and in what direction.
To predict rain or snowfall, a radar (RAdio Detection and Ranging) system sends a radio wave into the atmosphere. Radio waves bump into raindrops or ice crystals. They bounce back toward the radar system and make a echo or sound. The radar system measures how strong the echoes are, the direction from which they come, and how quickly they are returned. This tell scientists where clouds are, how fast they are moving, and how much rain or snow a cloud contains.
Video
Watch this review slideshow and take the quiz: Scholastic Study Jam.
Watch this video:
These Grade 5 students used a weather balloon to collect weather data high in the atmosphere.
How can I describe precipitation?
Materials
If air pressure goes up, the straw will move up. If air pressure goes down, the straw will move down.