Measurement of cloud angle for enhanced UVB at the Earth's surface

Paper


Sabburg, Jeff and Wong, Joe. 1999. "Measurement of cloud angle for enhanced UVB at the Earth's surface." Wong, Joe and Parisi, Alfio (ed.) 2nd Internet Conference on Photochemistry and Photobiology: Protection Against the Hazards of UVR 1999. 18 Jan - 05 Feb 1999
Paper/Presentation Title

Measurement of cloud angle for enhanced UVB at the Earth's surface

Presentation TypePaper
AuthorsSabburg, Jeff (Author) and Wong, Joe (Author)
EditorsWong, Joe and Parisi, Alfio
Journal or Proceedings TitleProceedings of the 2nd Internet Conference on Photochemistry and Photobiology 1999
Number of Pages9
Year1999
Web Address (URL) of Paperhttp://www.photobiology.com/UVR98/sabburg/index.htm
Conference/Event2nd Internet Conference on Photochemistry and Photobiology: Protection Against the Hazards of UVR 1999
Event Details
2nd Internet Conference on Photochemistry and Photobiology: Protection Against the Hazards of UVR 1999
Event Date
18 Jan 1999 to end of 05 Feb 1999
Abstract

This paper presents the results of a four-month study quantifying the effect of cloud and haze on enhanced UVB radiation (310 to 280nm) using a ground based sky camera system. The sky camera system is the first to measure cloud and haze properties near the sun, in contrast to whole sky assessment. images and radiation data were recorded every 6 minutes at Toowoomba, Australia (27.6° S). An image-processing algorithm estimated the amount and brightness of cloud and haze in an angular region of between 12.5 and 35 ° around the sun, as well as the amount of solar obstruction (sun not covered, partially or totally covered). It was found that UVB enhancement greater than 20 % occurred when maximum cloud area was at a 35° angle from the sun.

ANZSRC Field of Research 2020519999. Other physical sciences not elsewhere classified
370106. Atmospheric radiation
370107. Cloud physics
Byline AffiliationsCentre for Astronomy, Solar Radiation and Climate
Queensland University of Technology
Institution of OriginUniversity of Southern Queensland
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