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Prairie halos ~ From Roy Bishop. "Here is a photo I took many years ago on a bitterly-cold (-23C) January afternoon on the Canadian prairies. The view is looking west with a strong wind from the north filling the air near ground level with drifting snow. The person on the road is my son, then 5 years old."

©Roy Bishop, shown with permission

At left a ray tracing simulation using only plate crystals. Wobbly plates to produce the tall sundogs and pillar, better oriented plates for a defined parhelic circle through the sun.

There are other possibilities. If it is a diamond dust display, it could be brightest towards the horizon where the path length through a shallow layer of crystals is greatest. Some at least of the tall 'sundogs' could then be segments of a 22° halo. The pillar itself might be from column crystals.

There is not sufficient data. But why make too much analysis - a beautiful and achingly desolate scene is enough.