That's "magic wand" stuff, Tom. I was hoping you wouldn't say that and just go with "sinking" which you cited earlier as a "well known" refraction phenomenon without the necessity for mirage too. "Mirage" is in the territory of "waves" as an explanation for the effect, but oh well.
Whether it's mirage or merely refractive sinking, I've been trying to make sense of the "thin white line" explanation for the Turning Torso's "sinking ship" effect.
Here is an orthogonal, single ray-trace diagram of light from the Tower to the observation viewpoint of h=6.9' high from a distance of 29.8 miles for how light would be refracted given this theory:
371' (vertical angle of 0.135°) must be compressed into a band of about 4-5' (vertical angle of 0.002°) based on the thin white band visible at the boundary between sea and building in the photo (in-line at bottom of this post).
For the air refraction to cause that, somehow everything from 371' down must be bent into a narrow range, with everything above eye level (6.9') experiencing an upward bending path, gradually lessening until reaching eye-level and then becoming straight to slightly downward bending in the lowest 7' above Tower ground.
But from 371' and up -- the upper 252' of Tower -- light markedly experiences a sudden change in refraction, resulting in a large "sinking" displacement with little or no distortion (compression) at all. All light bending from 371' to 623' would be bent by the same upward-bending refractive index.
I have no explanation for how the atmosphere density or temperature gradient could induce such an effect. Perhaps you can work it out. If not, you're just using refraction terminology without reasoning through the application.
But the mystery deepens with a change in observer elevation. Just 18 minutes later, the observation point was shifted to 57.7' high. Same horizontal distance of 29.8 miles, here is that ray diagram:
The same type of profile, except now that dividing line between extreme compression and sinking with no compression is at an elevation of 205' instead of 371'. Again, I can find no explanation within the literature for atmospheric refraction that would account for such a phenomenon. The dividing line between extreme compression of the lower floors and sinking of the higher floors is still above eye-level. The angle is reduced, but what does that suggest, if anything? Has the weather or air mass through which the Tower was viewed changed in the time it took to relocate from 7' to 58' in altitude? If not, what's the connection to elevation change in this case and how does it explain, via refraction, the change from 371' to 205'? If so, what might have changed about the air? What refractive conditions produce this kind of effect? Are they common enough to account for any time the "sinking ship" is seen?
Look again at the photo images of the two views. At this expanded resolution, that suspect "thin white line" is 7 pixels high in both views. I see no indicator of mirage; but maybe it's just too compressed to see? If there's no mirage, that would mean that if refraction is the reason, then very extreme stooping + sinking is at work, with a sudden shift to no stooping but still extreme sinking. And the sudden shift between the two occurring inexplicably, but with nothing but a change in viewing height.
No offense, Tom, but if you had "magic wand" issues with refraction as an explanation for deviations from a geometric curve calculator in sphere earth observations, how can you not have the same skepticism with refraction of a much greater and more peculiar nature when trying to explain such large hidden values on a flat earth?
I figure that's more a rhetorical question at this point; serving as commentary on my evaluation of your ad hoc "thin white line" proposal for where that missing Tower elevation has gone.
In closing: