Interacting with nature by
K:
How to Offer Wild Birds Shelter in the Winter
Not all birds migrate south for the
winter. Winter is a hard season for birds, and many risk freezing to death
at night. It doesn't take much effort or money to provide shelter for them,
and it can make a huge difference to the little feathered guys!
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Sunrays breaking through the clouds
When the sun is behind the clouds, and I see sunrays
breaking through the clouds, are they really spreading out as they appear to be,
or, is this just an illusion? My opinion is that they are really parallel
or very close to parallel and can be compared to lines of perspective in art.
Ron, Marietta, Georgia
View from Beaucatcher Ridge, North Carolina. Photo courtesy of Grant W.
Goodge and NOAA.
Your analysis, Ron, is right on target. The rays that shine through gaps in
clouds do, indeed, form parallel columns of sunlight and cloud-shadowed
darkness. The rays appear to spread out from the hidden Sun in the same fashion
as a road seems to spread out from the horizon — perspective lines, but the rays
are actually parallel. Small specks of dust and particles scatter the
sunlight, making the rays visible. Here is a beautiful set of
photographs, illustrating
perspective lines and
crepuscular rays.
Further Reading
Peterson First Guide to Clouds and Weather by Vincent J. Schaefer and John
A. Jay
(Answered Feb. 18, 2008)
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