Beware of yellow snow
Introduction
The photograph on this page of Beware of yellow snow by Richard Webb as part of the Geograph project.
The Geograph project started in 2005 with the aim of publishing, organising and preserving representative images for every square kilometre of Great Britain, Ireland and the Isle of Man.
There are currently over 7.5m images from over 14,400 individuals and you can help contribute to the project by visiting https://www.geograph.org.uk
Beware of yellow snow
Image: © Richard Webb Taken: 12 Jan 2017
Sodium's emission spectrum has just two strong lines in the visible spectrum at a wavelength of around 589nm - in the yellow. Here sodium lights illuminate the snow covered car park of Dunblane High School. The lights also contain mercury which does provide a little light of other wavelengths, this allows slight colour differentiation. I believe the city of San Jose in California only has sodium lights. This is to allow 589nm to be filtered out by the telescopes of a nearby astronomical observatory and provide a virtual dark sky. Sodium lighting is being phased out now, with the availability of more energy efficient light emitting diode lights. The snow will be white again.
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Image Location
Latitude
56.183471
Longitude
-3.981798