Measurement of the reflection - Polarization pattern of the flat water surface under a clear sky at sunset

József Gál, Gábor Horváth, Viktor Benno Meyer-Rochow

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42 Scopus citations


Using 180° field of view imaging polarimetry, we measured the polarization characteristics (degree and angle of linear polarization) of the entire clear sunset sky and the reflection-polarization pattern of the flat water surface under this sky in order to test the validity of the earlier theoretical predictions made by Horváth, G. (1995) [Reflection-polarization patterns at flat water surfaces and their relevance for insect polarization vision. Journal of Theoretical Biology, 175, 27- 37] and Schwind, R., & Horváth, G. (1993) [Reflection-polarization pattern at water surfaces and correction of a common representation of the polarization pattern of the sky. Naturwissenschaften, 80, 82-83] on the fine structure of this reflection-polarization pattern. We compared the measured reflection-polarization pattern with the theoretical reflection-polarization patterns computed for single-scattering Rayleigh skylight and measured real skylight reflected from the flat water surface, the repolarization characteristics of which are described by the Fresnel theory. Analysing and comparing the theoretical and measured reflection-polarization patterns, we could establish that the earlier predictions of Horváth (1995) and Schwind and Horváth (1993) were correct. Contrary to other full-sky polarimeters, our 180° field of view rotating-analyzer imaging photopolarimeter is useful not only for sky measurements, but also for downward viewing polarimetry. It can be used in atmospheric optics as well as in biological investigations involving animal polarization vision and orientation on the basis of skylight polarization or water-surface-reflected polarized light.

Original languageEnglish
Pages (from-to)103-111
Number of pages9
JournalRemote Sensing of Environment
Issue number1
StatePublished - 2001

Bibliographical note

Funding Information:
This work was supported by a 3-year János Bolyai postdoctoral research fellowship received by G. Horváth from the Hungarian Academy of Sciences, and by a 1-year doctoral research fellowship received by J. Gál from the George Soros Foundation (grant number: 230/2/878). The grants OTKA F-025826 and T-034981 received from the Hungarian National Science Foundation are gratefully acknowledged. Further financial support came from Oulu University received by V.B. Meyer-Rochow. Many thanks are due to Prof. Rüdiger Wehner (Zoologisches Institut, Universität Zürich, Switzerland), who lent his Nikon fisheye lens to us for the measurements in Oulu. Many thanks are due to three anonymous referees for their valuable comments and suggestions.


  • 180° Field of view imaging polarimetry
  • Air-water interface
  • Celestial polarization
  • Fresnel reflection
  • Reflection polarization of skylight
  • Sunset sky
  • Twilight

ASJC Scopus subject areas

  • Soil Science
  • Geology
  • Computers in Earth Sciences


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