2006. május 7., vasárnap

Odd radius halos in Finland

Yesterday, 6 May 2006, odd radius halos were observed in a large area in Eastern and Central Finland. Odd radius halos observed during the day were mainly circular halos and plate arcs.

I photographed the display in Vaala, were it lasted for 3 hours. Photo shown here is made by stacking 24 photos which were taken during 10 minutes time. Unsharp mask has been used to show halo better. Visually halos of the display were not as clear as in this stacked photo, but all halos shown in this photo were also observed visually, except 35° halo which can be seen faintly on left. More photos are here.

Jenni Holopainen in Joensuu probably got best odd radius halos during the day. Her photos can be seen here and here. Marko Mikkilä observed odd radius halos in Nivala, Teemu Öhman in Äänekoski and Eero Savolainen in Kuusankoski. Photos by Mikkilä and Savolainen can be found also here.

3 megjegyzés:

  1. Looks like in some of the photos 9 degree halo shows column arcs to the left and right.

    VálaszTörlés
  2. Congratulation!!!

    Do you have an explanation, why Finnland have more Pyramidal-Displays as the rest of the world???? Yesterday there was no Jet Stream or another strange weather situation to you ...

    Pondering Greetings
    Claudia

    VálaszTörlés
  3. We often have odd radii in high pressure situation when weather turns much warmer than the average. Now it's been really warm.

    Maybe there is truly more high cloud odd radii up here. Or maybe we just notice them. Many of our observers are using convex mirrors that help a great deal in spotting the rare faint halos. In this display of course there was no need for mirror to realize what's going on.

    The lunar displays in March and April that contained odd radii were not spectacular in many locations. You looked out from the window and hardly even saw halo around the moon. But if you decide to go out and photograph it anyway, the odd radii halos show up in the photos.

    VálaszTörlés