How Doppler Works

• Doppler radio waves are emitted from an antenna and bounce off objects in the atmosphere. Objects they encounter reflect a sound image known as the Doppler effect back to the generating antenna for analysis, according to a National Weather Service education website on Doppler radar and weather.
  
  

Doppler Radar and Meteorology

• The main use for Doppler radar is in aiding meteorologists to obtain accurate readings and detect the movement of storms and tornadoes in the atmosphere. Changes are tracked by the Weather Surveillance Radar-1988 Doppler, according to the National Weather Service.
  
  

How Doppler Tracks a Storm

• Differences in frequency can be used to detect whether an object such as a storm is moving toward the antenna or away. The National Weather Service observes that a lower frequency indicates that the storm is moving away from the antenna; a higher frequency means it is moving toward the antenna.
  
  

Tracking Speed and Intensity

• Doppler radar is used to track both the speed and the intensity, or strength, of a storm--vital in terms of tornadoes, blizzards and hurricanes, according to the Tornado Chaser website. Storms can lose and gain speed and intensity in a matter of hours; Doppler radar provides accurate timely warnings to communities in danger.
  
  

Other Vital Uses for Doppler Radar

• Radar guns employing the Doppler effect are used by traffic enforcement police nationwide to detect speeding motorists. The U.S. Army uses Pulse Doppler Radar, a system that accurately detects military targets via bearing range, altitude and radial velocity.