Atmospheric halos provide means to estimate shapes
and orientations of airborne ice crystals
J. Ruoskanen
- Finnish Defence Forces Technical Research Centre, Electronics- and information technology division, P.O. box 10, FI-11311 Riihimaki, Finland.
The shapes of ice crystals in tropospheric clouds have been examined with various techniques. An efficient addition to the methods is provided by halo phenomena arising from reflection and refraction of sun light in airborne ice crystals. This paper describes the extent to which conclusions of ice crystal properties can be drawn based on analysis of visible halos. The associations of ice-crystal orientations and shapes with halo forms can be examined with a Monte-Carlo simulation algorithm using geometrical optics.