Radar Observer · Propagation — Super-Refraction / Ducting
Super-refraction (ducting) of radar energy tends to:
- AAlways reduce detection range to zero
- BIncrease detection ranges well beyond normal, sometimes causing distant targets to appear and second-trace echoes✓ Correct
- CHave no effect on radar
- DOnly affect bearing accuracy
Explanation
When a temperature inversion / humidity gradient bends the beam downward more than usual (super-refraction or ducting), targets are detected at abnormally long ranges. Sub-refraction does the opposite, shortening ranges and possibly hiding targets that would normally be seen. Both are weather-dependent and unpredictable.
Authority: Bowditch (Pub. No. 9), Radar Propagation
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