Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

Visibility of halos and rainbows

Not Accessible

Your library or personal account may give you access

Abstract

A theory for the visibility of halos and rainbows is presented. The light reaching the observer’s eye from the direction of the halo or rainbow is assumed to consist of two parts: (1) a beam of singly scattered sunlight (or moonlight) from a cloud of ice crystals or a rainswath, which, in turn, has suffered depletion by scattering or absorption in its passage to the observer, and (2) the general background brightness. The model is able to account for several long-known qualitative observations concerning halos, namely, that the brightest halos are produced by optically thin cirrostratus clouds (i.e., for which the cloud optical depth τc ≤ 1) and that when the sun is low in the sky the top of the halo is visible much more frequently than the bottom. (This is shown to result in good part from extinction by the turbid atmosphere.) With the rainbow the brightness of the beam increases monotonically with the optical depth τR of the sunlit part of the rainswath, but the increase is quite small for τR ≥ 1. On the other hand, the brightness of the background increases more rapidly with τR for τR > 1 so that the rainbow appears most easily visible for τR ≲ 1. This implies that the most easily visible rainbows are produced by light or moderate showers rather than heavy downpours. Finally, suggestions are made for applying the theory to other atmospheric optical phenomena, such as coronas and glories.

© 1980 Optical Society of America

Full Article  |  PDF Article
More Like This
Simulating rainbows and halos in color

Stanley David Gedzelman
Appl. Opt. 33(21) 4607-4613 (1994)

Simulating halos and coronas in their atmospheric environment

Stanley David Gedzelman
Appl. Opt. 47(34) H157-H166 (2008)

Visibility of stars, halos, and rainbows during solar eclipses

Gunther P. Können and Claudia Hinz
Appl. Opt. 47(34) H14-H24 (2008)

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Figures (6)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Equations (17)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved