Radar Ducting
The following are some extreme examples of radar ducting. These images were saved on July 10, 2008. The radar site is Milwaukee, Wisconsin (KMKX). The ducting occurred during the afternoon hours.
If the atmospheric condition that causes superrefraction bends the beam equal to or more than the earth's curvature then a condition called ducting, or trapping, occurs. Ducting often leads to false echoes also known as anomalous propagation or simply AP. On the images below there are multiple "skipping" echoes.
Image from
JetStream - online school.
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