This outstanding superior mirage/Fata Morgana lasted for several hours. It was viewed from ~4m above sea level. There was no wind and the air temperature was ~6C.
The mirage was the result of the atmospheric density gradients produced by a temperature inversion. The ice strewn sea cooled the air in contact with it forming an unusually cold layer beneath warmer air.
Upward going rays from distant objects are refracted back downwards by the different density air layers and to the eye the miraged object appears to be floating in the air. The direction of refraction is to curve rays towards denser colder air. Where refraction is strong and there is ray crossing the upper image is inverted. In this example the refraction has produced vertical magnification and exaggeration, a characteristic of Fata Morgana mirages.
Is the mirage of ice floes or of the 50-60 km distant mountains of Spitsbergen?
Atmospheric refraction, green flash and mirage expert Andrew Young comments: �I'm inclined to think it was land and not ice that was miraged. However, there are some offshore islands that might have been the targets, rather than the body of Spitsbergen itself.
The features certainly appear to be snow-covered rocks, not just ice.
I think this can be classified as a Fata Morgana, though it doesn't produce the classical illusion of architectural features. There are at least 7 images almost everywhere; in some places, I'm sure there are 9. And maybe some of the complex structure at the right shows 11 images in a few places. This is certainly a fine display!�
Steinar Midtskogen who has traveled the area kindly dug out a marine chart on which the map at right is based. The island of Wilhelmøya was possibly miraged combined with more distant high ground on Spitsbergen itself.
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