Phénomènes de réfraction atmosphérique terrestre

This article presents, almost without any analytical analysis, an orderly and illustrated presentation of the atmospheric—or terrestrial—refraction effects, i.e., affecting vision apparent shape position objects located in atmosphere, contrary to case astronomical refraction. The adopted classification, which is non-exhaustive as there are still mysterious atypical cases, mostly based on transfer curves value refraction coefficient κ. Beginning with mirages, i.e. when inverted image formed, four main types identified: inferior, superior, Nachspiegelung mock-mirage, multiple mirage. Then comes special Fata Morgana: their archetypal form a transition whose physical cause remains imperfectly understood, real forms more complex varied, although often linked superior mirages. Finally remain unusual cases image: stooping/stretching, sinking, looming, finally hillingar effect—corresponding strong looming (κ>1) giving illusion that flat horizontal surface, e.g., sea, concave.