At 10:30 AM 11/10/99 -0600, Joel Wilcox wrote:
[snip]
>
>Thanks Garth. These "above" and "below" perspectives are obviously
>anthropocentric. Should I assume because of the name that it is usually
>seen at high noon or some such? It looks a little like a sundog, without
>the prism effect.
Joel:
Best I can do is quote from the National Audubon Society's Field Guide to North
American Weather (pp. 554, 555):
"Sun Pillars, Parhelic Circle, and Subsun
Description: Vertical, horizontal, or disklike reflections in the sky.
Reflection phenomena are colourless unless the sun itself is red.
Environment: Unlike parhelia, arcs, and haloes, which are caused by light
refracted through ice crystals, sun pillars, parhelic circles, and subsuns are
caused by reflection of light. Ice-crystal plates fall flat, and ice-crystal
columns fall on one of the six sides; in both, the longest dimensions are
oriented horizontally. Horizontally oriented ice-crystal plates (occurring in
cirriform clouds or in ice fog near the earth's surface) reflect sunlight into
vertical sun pillars above the rising or setting sun. Sun pillars may also be
seen below the sun. The subsun, an image of the sun reflected from horizontal
ice-crystal plates, is seen beneath the horizon from mountains or airplanes.
...
Season: All year.
Range: Throughout North America."
Now, re-reading Christoph Hertzler's and Ken Norton's posts, I'm not sure that
this really *is* an analogue to the subsun. What complicates matters for me is
that several of these optical phenomena can be happening simultaneously
according to the Guide, thus making a real determination almost impossible. If
it truly is a reflection, then I'd vote for a variation on subsun, 'cause the
cloud in the picture looks kinda cirriform to me -- otherwise, some type of
refraction (damn, I'm good! -- cover off every possible base in one sentence!
8^> ). Mebbe you want to bring this photo to the attention of your local
weather guru and see what he/she says.
Garth
"A bad day doing photography is better
than a good day doing just about
anything else."
The Unofficial Olympus Web Photo Gallery at:
http://www.taiga.ca/~gallery/
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