Wednesday, 13 December 2006

Diamond dust haloes in the German Alps

On 11th of december 2006 I saw a wonderful diamond dust phenomenon in the Wendelstein area in the altitude of ca. 1100m. It was the best in my life! I was a part of it and around me floated ice crystals with different white and coloured arcs. Directly over my head was formed an aura, the upper tangent arc I could touch and on the opposite side of the sun were some white arcs crossed in three-dimensional space.

The origin of ice crystals were definitely natural. The clouds came from the very cold Inn valley and creeped up the mountain sattle. The sun elevation was 18 to 20 degrees.

I've seen with naked eye the following haloes: : 22° halo, upper and lower tangent arc (extremely bright!), complete sun pillar, 46°halo (very faint lower part), complete parhelic circle, anthelion, 120deg parhelia, infra- and supralateral arcs, Wegeners anthelic arc (one of the cross bows), Tricker's and diffuse anthelic arcs, heliac arc, subhelic arcs and Moilanen arc.

More pictures are here.

By Claudia Hinz

Wednesday, 6 December 2006

Diamond dust halos over open sea

It is not so often to see diamond dust halos over the open sea, like here in the photograph of Pasi Snellman, taken on 5 November in Porvoo, Southern Finland. The display occurred only above the sea indicating that the open water was the moisture source for ice crystal growth. A couple of of kilometers upwind from the bridge is a small ski center, and according to Snellman snow making was under way there.

This may have provided the nuclei for the ice crystal formation. Snellman also tells that the air temperature was -7° C and sea +5° C.

On 5 November good diamond dust was seen also in Jämsä and Lahti, the latter of which is not reported here in Haloreports.

By Marko Riikonen