How Doppler radars work
MANILA, Philippines—Doppler radars are capable of detecting not only rain movement but the intensity of precipitation. They can detect the presence and location of rainfall and other kinds of precipitation by bouncing radio waves off it and calculating the time it takes for that signal to return.
Objects in the air (i.e. raindrops, snow, hail) scatter or reflect radio waves sent by a Doppler radar back to that radar’s antenna. In turn, the radar electronically converts the reflected radio waves into pictures depicting the location and intensity of precipitation.
Doppler radars use the Doppler effect, which states that there is a shift in the frequency of waves bouncing off a moving object and that the shift is related to the object’s speed in relation to an observer.
The Doppler effect is named after Christian Doppler, an Austrian physicist. Inquirer Research