| Concept definition: |
A layer of the <ATMOSPHERE> that is over a <WATERBODY> and in which electromagnetic waves launched in certain <DIRECTION>s are guided by and/or trapped within the layer rather than propagating radially from their source, caused by a decrease in <<WATER_VAPOUR_PRESSURE>> with <<HEIGHT_AGL>> due to evaporation; electromagnetic refractive evaporative duct. |
