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Applied Optics

Applied Optics

APPLICATIONS-CENTERED RESEARCH IN OPTICS

  • Vol. 39, Iss. 21 — Jul. 20, 2000
  • pp: 3612–3619

Skerrylike Mirages and the Discovery of Greenland

Waldemar H. Lehn  »View Author Affiliations


Applied Optics, Vol. 39, Issue 21, pp. 3612-3619 (2000)
http://dx.doi.org/10.1364/AO.39.003612


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Abstract

The Norse discovery of Greenland is associated with the sighting of low barren islands called Gunnbjörn’s Skerries, which have never been satisfactorily identified. Here the historical references that connect the skerries to Greenland are reviewed. A mirage of the Greenland coast, arising specifically from optical ducting under a sharp temperature inversion, is used to explain the vision of skerries seen by the Norse mariners. Images from both ducting and uniform inversions are calculated. Under the assumption of a clean Rayleigh atmosphere, sufficient visibility remains to see the skerry image at a distance of 220 km. There is significant circumstantial evidence to indicate that the Norse were familiar with the skerrylike mirage and that they used it to discover new lands.

© 2000 Optical Society of America

OCIS Codes
(000.2850) General : History and philosophy
(010.0010) Atmospheric and oceanic optics : Atmospheric and oceanic optics
(010.4030) Atmospheric and oceanic optics : Mirages and refraction

Citation
Waldemar H. Lehn, "Skerrylike Mirages and the Discovery of Greenland," Appl. Opt. 39, 3612-3619 (2000)
http://www.opticsinfobase.org/ao/abstract.cfm?URI=ao-39-21-3612


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References

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