Abstract

Using purely geometric considerations, a sequence of mountain shadow models is considered. The observer is located at the summit of idealized mountains with several different cross-sectional profiles. The result for a triangular profile is generalized to the case of an off-summit observer. We also examine the case of a conical mountain. In addition, a simple geometric model is formulated for mountain “spikes” in terms of the differences in shadow length and contrast for an off-summit observer within the shadow. The first appendix is devoted to the notion of “umbral volume” and the second to the geometry of sunlit areas on a conical mountain.

© 2017 Optical Society of America

Mountain shadow phenomena

William Livingston and David Lynch
Appl. Opt. 18(3) 265-269 (1979)

Mountain shadow phenomena. 2: The spike seen by an off-summit observer

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