Home
  OpticsPOD
  What's New 
  Rays & Shadows
  Water Droplets
  Rainbows
  Ice Halos
    Contents
    Crystals
    Frequent Halos
    Infrequent Halos
      Why infrequent?
      46° Halo 
      Supra/infralateral
      Parry Arcs
        Images
        1  2  3  4 
      Lowitz Arcs
      Moilanen Arc
      Kern Arc
      120° Parhelia
      44° Parhelia
      Subhorizon Arcs
      Pyramidal
    Multiple Displays
    Other Worlds
    Observing Halos
    HaloSim
  High Atmosphere
  Links & Resources
  Search - Index






 
123456789012345678


   Parry Arc II 


  

Sunvex and suncave Parry arcs.
When the sun is less than 15° high look out for the rare sight of two Parry arcs above the tangent arc.

The uncommon "sunvex" arc, so named because it is convex towards the sun, is best seen at solar altitudes of 7-12°. Its position relative to the suncave arc changes quickly as the sun's altitude alters.

Artist Loren Hall pictured the two arcs on an early spring afternoon in 1991 at Rome, Georgia.

The bright display also had a supralateral arc from singly oriented columns and plate crystals produced a coloured circumzenithal arc. The HaloSim simulation below matched the halos using a solar altitude of 11.7
°.

Photo ©Loren Hall, shown with permission.