Anomalous celestial polarization caused by forest fire smoke: why do some insects become visually disoriented under smoky skies?
Author
Summary, in English
The effects of forest fire smoke on sky polarization and animal orientation are practically unknown. Using full-sky imaging polarimetry, we therefore measured the celestial polarization pattern under a smoky sky in Fairbanks, Alaska, during the forest fire season in August 2005. It is quantitatively documented here that the celestial polarization, a sky attribute that is necessary for orientation of many polarization-sensitive animal species, above Fairbanks on 17 August 2005 was in several aspects anomalous due to the forest fire smoke: (i) The pattern of the degree of linear polarization p of the reddish smoky sky differed considerably from that of the corresponding clear blue sky. (ii) Due to the smoke, p of skylight was drastically reduced (p(max) <= 14%, p(average) <= 8%). (iii) Depending on wavelength and time, the Arago, Babinet, and Brewster neutral points of sky polarization had anomalous positions. We suggest that the disorientation of certain insects observed by Canadian researchers under smoky skies during the forest fire season in August 2003 in British Columbia was the consequence of the anomalous sky polarization caused by the forest fire smoke.
Department/s
Publishing year
2007
Language
English
Pages
2717-2726
Publication/Series
Applied Optics
Volume
46
Issue
14
Links
Document type
Journal article
Publisher
Optical Society of America
Topic
- Biological Sciences
Status
Published
Research group
- Animal Navigation Lab
ISBN/ISSN/Other
- ISSN: 2155-3165