|
meteoptic-l [ät] ursa.fi
message archive
This is meteoptic-l [ät] ursa.fi message archive.
Note, your can reply the messages on this page only if your
are already subscribed the list.
» To the end of the list/message
Dear Marko, (Marko Pekkola)
I am not sure that all members of the metopitics discussion forum are
interested in our discussion. I appreciate your paper on elliptical halos
in weather. So, I wonder why you do not write a paper on the explanation
of elliptical halos by pyramidal crystals. I guess, the reason is that
you do not trust your computersimulations. I am sorry, but I prefer to
continue the discussion of the details after having analysed the photo
of the colored elliptical halos by myself and after having read an English
version of your article on elliptical halos in the Finish journal.
But I like to clarify two points of the previous discussion:
1) In our paper we write that from a critical review of the 23 reports
and from interviews of the Finish observers in June 1995 it is evident
that most of the elliptical halos occured in the snowy virga of
altocumulus clouds. Is this still correct ?
2) I wrote in my last email that our model does not predict color
separation of the rings because they are produced by multiple reflections.
Indeed, multiple reflections is the main rayclass. However, there are
small
contributions from other rayclasses including refraction. Unfortunately we
did not check in the simulations the amount of these contributions. So,
the
model is consistent with the observation of slightly colored rings.
By the way, there are a few displays which directly show the effect of
multiple scattering. I have a slide of the 18.2.88 display showing
that the intensity of the ring varies along the ring. The intensity
decreases
towards the horizon. This is easily explained by multiple scattering
without specifying a detailed model of the ice cloud. The rays with small
altitude angle cannot leave the horizontally extended cloud but are
scattered
once more before they leave the cloud. I wonder why you did not publish
this
interesting photopraph of the 18.2.88 display but another one that only
shows
the upper part of the ring.
Best regards to all of you
Eberhard Traenkle
|