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Applied Optics

Applied Optics

APPLICATIONS-CENTERED RESEARCH IN OPTICS

  • Vol. 42, Iss. 3 — Jan. 20, 2003
  • pp: 445–457

Measuring and modeling twilight’s purple light

Raymond L. Lee, Jr. and Javier Hernández-Andrés  »View Author Affiliations


Applied Optics, Vol. 42, Issue 3, pp. 445-457 (2003)
http://dx.doi.org/10.1364/AO.42.000445


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Abstract

During many clear twilights, much of the solar sky is dominated by pastel purples. This purple light’s red component has long been ascribed to transmission through and scattering by stratospheric dust and other aerosols. Clearly the vivid purples of post-volcanic twilights are related to increased stratospheric aerosol loading. Yet our time-series measurements of purple-light spectra, combined with radiative transfer modeling and satellite soundings, indicate that background stratospheric aerosols by themselves do not redden sunlight enough to cause the purple light’s reds. Furthermore, scattering and extinction in both the troposphere and the stratosphere are needed to explain most purple lights.

© 2003 Optical Society of America

OCIS Codes
(010.1290) Atmospheric and oceanic optics : Atmospheric optics
(330.1710) Vision, color, and visual optics : Color, measurement
(330.1730) Vision, color, and visual optics : Colorimetry

History
Original Manuscript: January 18, 2002
Revised Manuscript: May 13, 2002
Published: January 20, 2003

Citation
Raymond L. Lee and Javier Hernández-Andrés, "Measuring and modeling twilight’s purple light," Appl. Opt. 42, 445-457 (2003)
http://www.opticsinfobase.org/ao/abstract.cfm?URI=ao-42-3-445


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