Wind Weather Instruments

Anemometer

• Anemometers are the most common wind weather instruments. Some anemometers measure wind speed, others measure air pressure. Since these two properties are closely related, measurements of one property can be used to infer values for the other. Anemometers use different principles to measure the speed and direction of wind. Anemometers can be as simple as plastic-foam cups, which spin in the wind and give a rough estimate of wind speed, to devices using ultrasonic and laser technologies to make measurements.

Rawinsonde

• A rawinsonde is a variation of a platform of instruments known as a radiosonde, which can be used to determine wind speed and direction. A rawinsonde is usually attached to a balloon and launched into the upper atmosphere to make a wider array of measurements. Rawinsondes transmit information and data using radio signals, allowing scientists to make real-time measurements. In addition, rawinsondes contain several other instruments to measure air pressure and temperature.

Radar

• Radar uses electromagnetic radiation (specifically, radio waves) to identify the position or speed of objects. A variation of radar, known as Doppler radar, measures wind speed. These instruments use the Doppler effect to analyze changes in the frequency of an electromagnetic wave after it is reflected off molecules in the atmosphere. This frequency shift helps determine wind speed and is frequently used for large-scale weather measurements.

SODAR

• SODAR (SOnic Detection And Ranging) is a method of wind measurement similar to radar. Instead of electromagnetic radiation, however, SODAR uses sound waves to determine wind speed by detecting changes in their frequency after they are reflected by the atmosphere.

LIDAR

• LIDAR or Light Detection And Ranging is also similar to radar. LIDAR uses electromagnetic radiation in the visible light spectrum. Analyzing frequency changes resulting from reflections of light pulses in the atmosphere can determine wind speed.