Earlier quoted context omitted.
The schematic here on Wikipedia might help clarify: https://commons.wikimedia.org/wiki/File:Fada_morgana_graphnn... If instead of layers of warm/cold air there were giant glass lenses hovering over the ocean, the mirage wouldn’t be mysterious.
I think they were attempting a joke. Hot-road mirage is a common thing that most people that were in a car trip during summer have seen, same principles.
I’m aware it was a joke :) But I think the confusion was sincere; the explanation in the article is lacking if you don’t have a clear picture to begin with.
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