Editing Anomalous propagation (section)

==== Super refraction ====
{{redirect|Super refraction|the music album|Super Refraction}}

It is very common to have [[temperature inversion]]s forming near the ground, for instance air cooling at night while remaining warm aloft. This happens equally aloft when a warm and dry airmass overrides a cooler one, like in the [[Subsidence (atmosphere)|subsidence]] aloft cause by a high pressure intensifying. The index of refraction of air increases in both cases and the EM wave bends toward the ground instead of continuing upward.

On surface-base inversion, the beam will eventually hit the ground and a part of it can be reflected back toward the emitter. In upper air inversion, the bending will be limited to the layer involved but the bending will extend the path of the beam, possibly beyond the usual transmission horizon.