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Dear Mark and others,
| Dear members of this mailing list,
| recently we received an interesting photograph of a rainbow that is
| caused by sunlight reflected on a water surface. Visible is the common
| primary bow, the secondary bow and the "mirror-bow". I know only 5 or 6
| photographs that show these unusual rainbows. The brightness is about
| 1/3 of the primary bow. The photo was taken at the coast of the northern
| sea during low tide. There were a lot of puddles with calm water,
| reflecting the sunlight.
Great! I have try to hunt those reflected-light rainbows without any
success so
far.
| I think it is possible that also halos can be caused by reflected
| sunlight. E.g. halos in ice-fog above a frozen lake. Probably also
| secondary halos to the subsun do exist. What do you think?
Yes they can. If we have halos in anthelion region in that kind of
situation
you should have also halos which are above horizon. Those reflected
subhorizon
halos would look just like those "normal" halos since most of subhorizon
halos
are mirror images of halos above horizon. Reflected subhorizon halos won't
be
as well defined as those "normal" halos.
In a case when we have those halos around sun, some extra halos are
possible
such as "reflected upper tangent arc". This "reflected upper tangent arc"
is
not located 22 degree above sun but 22 degree above subsun and it would be
a
upside-down version of lower tangent arc. I think that this reflected
tangent
arc would be possible to observe if you have right settings (mirror flat
ice or
water surface between you and sun and a diamond dust display).
Many reflected forms are possible but it would be practically impossible
to
separate most of them from normal haloforms. E.g. reflected parhelia are
also
possible when you have plate ice crystals on a mirror-like surface (like
roof a
car). I have seen those couple of times. Problem is that should you call
those
as reflected parhelia or as subparhelia (or grounded subparhelia?)?
| Regards,
| Mark Vornhusen (Arbeitskreis Meteore e.V.)
|
| Homepage AKM: http://www.meteoros.de
Jarmo Moilanen
Finnish Halo Observing Network.
FHON Homepage: http://www.ursa.fi/ursa/jaostot/halot/
|