2010. február 28., vasárnap

Tapes arc, helic arc and subhelic arc observed in Austria

Last January, 27 th, I managed to get one of my best halodisplays during my long observation period of halos - I have observed these phaenomena more than 15 years already.

On my way home from work I observed 14 different haloforms within 1 and a half hour (14:15 - 15:45 CET). It started with a bright circumzenith arc, sundogs and a clearely vertically elongated left hand side 120° parhelion on a short parhelic circle. Later the 120° parhelion on the right hand side appeared. The highlight (about 15:15 CET) was the observation of the CZA, supralateral arc, 46° halo, suncave and sunvex Parry arcs, upper tangent arc, 22° halo with sundogs, Tape arc, helic arc, subhelic arc and a little bit later a small part of the left infralateral arc.

I run a simulation with Halosim from L. Cowley and M. Schroeder that shows the halos I have observed near the sun quite good. A report and many images can be seen by clicking the image above. I invite you to take a look at the site.

Karl Kaiser

7 megjegyzés:

  1. And Wegener arc!

    VálaszTörlés
  2. I have difficulties to figure out this display, especially the subhelic arc. Sometimes I think that it is just parhelic circle. The simulation is not much help. It is should be centered on the side, rather than on the sun.

    VálaszTörlés
  3. Thats just amazing Karl I like that tape arc and the subhelic arc. I've seen helic wegener arcs in cirrus back in 2006 but in 09 I got wegener three times and in the one display I got my first tricker arc.

    VálaszTörlés
  4. Dear Marko,

    Parhelic circle should be seen symmetrically in the images with vertical symmetryaxis. My camera was in a horizontal position as we see (look at the trees in the middle of my image - http://home.eduhi.at/member/nature/met/HALO/phaen2010-01-27/35komb.htm). In my pics subhelic arc stretches from right hand side up to left hand side down.
    I remember the height of the trees was much more than the elevation of the sun. In 2 hours, on my way to work, I check it out.

    Have a nice day.

    Best regards from Schlaegl,

    Karl

    VálaszTörlés
  5. Ok, Karl, yes, I believe now! A great display!

    VálaszTörlés
  6. I measured the height of the spruce you see in the image mentioned above - it´s about 22°. The subhelic arc was located much higher in the sky!


    Karl

    VálaszTörlés
  7. Dear Patrik,

    Thank you for analysing my images! Actually Wegeners arc is in the pics - I have added another unsharp masked image to the gallery: http://home.eduhi.at/member/nature/met/HALO/phaen2010-01-27/34u.a.htm

    Have a nice evening,

    Karl

    VálaszTörlés