OSA's Digital Library

Applied Optics

Applied Optics

APPLICATIONS-CENTERED RESEARCH IN OPTICS

  • Editor: Joseph N. Mait
  • Vol. 50, Iss. 28 — Oct. 1, 2011
  • pp: F1–F5

Elliptical pollen corona from North American boreal paper birch trees (Betula papyrifera): strong fall orientations for near-spherical particles

Kenneth Sassen  »View Author Affiliations


Applied Optics, Vol. 50, Issue 28, pp. F1-F5 (2011)
http://dx.doi.org/10.1364/AO.50.0000F1


View Full Text Article

Enhanced HTML    Acrobat PDF (518 KB)





Browse Journals / Lookup Meetings

Browse by Journal and Year


   


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools

Share
Citations

Abstract

It has only recently been realized that solar corona can be generated by dispersions of tree pollen grains suspended in the atmosphere, and these studies have come almost exclusively from Scandinavia. Using corona photographic and surface pollen analyses, it is shown here that paper birch trees in the interior of Alaska regularly generate solar corona during the boreal green-out in mid-May. Although near-spherical in shape, these 27 μm average diameter particles have three surface protrusions involved in germination that are indicated to aid in the generation of elliptical corona, for which a strong preferential particle orientation is needed. For observations at solar elevation angles of 35 ° 40 ° , an axis ratio of about 1.2 and average radius of 2.5 ° (for the second-order red band) are found. Because oriented particles of a particular shape tend to fall slower than randomly oriented ones, this microdesign promotes the lateral spread of pollen and enhances tree reproductive opportunities, an especially important trait for pioneering species.

© 2011 Optical Society of America

OCIS Codes
(010.1100) Atmospheric and oceanic optics : Aerosol detection
(010.1290) Atmospheric and oceanic optics : Atmospheric optics
(010.3640) Atmospheric and oceanic optics : Lidar

History
Original Manuscript: January 28, 2011
Revised Manuscript: March 21, 2011
Manuscript Accepted: April 5, 2011
Published: July 7, 2011

Virtual Issues
Vol. 6, Iss. 11 Virtual Journal for Biomedical Optics

Citation
Kenneth Sassen, "Elliptical pollen corona from North American boreal paper birch trees (Betula papyrifera): strong fall orientations for near-spherical particles," Appl. Opt. 50, F1-F5 (2011)
http://www.opticsinfobase.org/ao/abstract.cfm?URI=ao-50-28-F1

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited