09-04-2012, 01:45 PM
Technical seminar on Doppler Radar
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INTRODUCTION
Doppler radar: A radar that can determine the frequency shift through measurement of the phase change that occurs in electromagnetic waves during a series of pulses.
Works on doppler effect
It was invented by Christian Doppler, a physicist from Austria, in 1842
Doppler worked out his ideas using sound waves.
How does Doppler radar work
It obtains weather information (wind and precipitation) based upon returned energy.
Then it emits a burst of energy. If the energy strikes an object (rain drop, bug, bird, etc), the energy is scattered in all directions. A small fraction of that scattered energy is directed back toward the radar.
Doppler effect
Austrian physicist Christopher Doppler proposed it in 1842,
It is the change in frequency of a wave for an observer moving relative to the source of the waves.
It is commonly heard when a vehicle sounding a siren approaches, passes and recedes from an observer. The received frequency is increased (compared to the emitted frequency) during the approach, it is identical at the instant of passing by, and it is decreased during the recession
Why is Doppler Radar Important?
It detects severe weather events that threaten life and property.
It detects large hail, damaging winds, tornadoes, and locally heavy, flooding rain.
More importantly, this severe weather is seen by the Doppler radar more definitively than with the old conventional radar.
Disadvantages
Disadvantages of the Doppler are that its increased sensitivity means that in severe weather, it stands a higher chance of failure.
The equipment also needs higher maintenance
CONCLUSION
Using doppler radar we can have instant access to storm relative velocity, Wind Profiles, precipitation estimates, storm cell data, and MUCH more. It helps us to stay smart & stay safe ….