Alaska Lower Tangent Arc

Tangent arc index

Lower tangent arc and other halos. When the sun is low the horizon hides the lower tangent arc but it can be seen from from hills or mountains when there are clouds or cold air below containing the necessary ice crystals. Ryan Skorecki (site) caught these arcs at Girdwood Alaska. ©Ryan Skorecki, reproduced with permission.
The HaloSim simulation for a solar altitude of 6º.   The bright subsun and part of the lower sun pillar in the image were partly produced by reflection from the water or ice of Turnagain Arm deep in the valley.