
Doppler effects are used in many types of technology, and this is one example of using Doppler effects to work meteorology. The common design of the weather radar is a radar that covers with the sphere material around it (we can find this in Cambodia, it’s after the Chbar Ampov bridge there is a big ball and there is a radar inside there). The full word of radar is RAdio Detecting And Ranging. Doppler radar has a transmitter and a receiver. The transmitter transmits microwaves in 360 degrees into the atmosphere, and then the receiver is waiting to receive those signal that will return back. The signals that receive is called the radar echo. Precipitation is the one that reflects the microwaves back. The information that the receiver receives is in two form: relative and velocity. Relative tells where the precipitation is; the velocity, happens only in the Doppler radar, output the velocity of the wind. If the frequency is high the precipitation is moving toward the radar; if the frequency low the precipitation is moving away from the radar. Here is an example, “If particles switch from moving toward and then away from the Doppler radar over a small distance, the source may be a tornado.” As a result, Doppler effects benefits a lot to human, the concepts can save people’s life from storms like a tornado.