Abstract

The results of a quantitative treatment of the visibility of the circumzenithal arc as a function of solar elevation are compared with records of the arc’s occurrence in France and the Netherlands, 1894–1931. Both calculated and observed frequency distributions peak at a solar elevation of 22° (minimum deviation), and the width of the observed frequency distribution can be closely matched with the assumption that plate ice crystals in quiet air undergo oscillations of around 1° from equilibrium. This result agrees with other estimates based on studies of the subsun and parhelic circle. The circumzenithal arc is shown to be vertically polarized, with I_vert/I_hor ≈ 1.4 in the solar vertical near minimum deviation.

© 1979 Optical Society of America

Polarization models of halo phenomena. I. The parhelic circle

David K. Lynch
J. Opt. Soc. Am. 69(8) 1100-1103 (1979)

Arcs of Lowitz

James R. Mueller, Robert G. Greenler, and A. James Mallmann
J. Opt. Soc. Am. 69(8) 1103-1106 (1979)

What size of ice crystals causes the halos?

Alistair B. Fraser
J. Opt. Soc. Am. 69(8) 1112-1118 (1979)

Geometry of halo formation

Walter Tape
J. Opt. Soc. Am. 69(8) 1122-1132 (1979)

Blue spot on the parhelic circle

Mika Sillanpää, Jarmo Moilanen, Marko Riikonen, and Marko Pekkola
Appl. Opt. 40(30) 5275-5279 (2001)