Weather Radar - Limitations and Artifacts

Limitations and Artifacts

Radar data interpretation depends on many hypotheses about the atmosphere and the weather targets. They are:

• International Standard Atmosphere.
• Targets small enough that they obey the Rayleigh scattering so the return is proportional to the precipitation rate.
• The volume scanned by the beam is full of meteorological targets (rain, snow, etc..), all of the same variety and in a uniform concentration.
• No attenuation
• No amplification
• Return from side lobes of the beam are negligible.
• The beam is close to a Gaussian function curve with power decreasing to half at half the width.
• The outgoing and returning waves are both polarized similarly.
• There is no return from multiple reflections.

One has to keep in mind that these hypotheses are not necessarily met in many circumstances. One has to be able to recognize the truth from the false echoes.