The Story of SNOW

18 02 2010

I found Jon’s post regarding the Magono-Lee Snow Crystal classification system to be quite interesting.  Here are some more shots from Monday night – I’ll see if I can classify them… something tells me that will be more difficult than it sounds. Let’s start with something simple.  My first guess is that the two crystals that  follow would be classified as  P2d  – Dendrite with Sector-like ends:

It looks like that crystal bumped into a couple of simple plates along the way, and they are stuck to it in the lower right quadrant. The one below has one spot of rime on it – which I assume is not enough to knock it into the rimey category, so it too is a P2d:

This one is similar in general form to the one above, but has a bit of rime spotting it up. I guess it would fall under rimed stellar R1d under Magono-Lee’s system. Personally, I think it would make more sense to have rime as a qualifier of the basic shape, so if I was cooking up a classification scheme I’d call this a Dendrite with Sector-like ends with moderate rime. Maybe P2d-r2.

The next one is a 12 branched crystal without rime, so it is either a P4a (broad branched with 12 branches) or a P4b (dendrite with 12 branches.) Personally, I’d call it a 12 branched variant of the P2d formation, which we just saw above. Maybe P2d-2x? Well – under the existing system it is either a P4a or P4b…

You may have noticed what looks like a sectored plate emerging from one arm at about the 8 o’clock position – that appears to be a growth at the end of that arm. OK – let’s get back to something simple.  I think the following are all ordinary dendrites – P1e. This first one has a ‘crack’ in the center plate – something I’ve seen several times. I’m not sure what causes it.

And I’ll close out with three rimey subjects, the first two would be R1d – Rimed Stellar and, I think, the last one would be R2b – Densely Rimed Stellar. Though one might think it was a densely rimed fernlike stellar dendrite – maybe P1f-r3, eh?

Magono-Lee is an interesting classification system. I don’t understand exactly why it places such an emphasis on rime at the expense of the core structure of the crystal. It seems to me that rime is an incidental condition independent of the core structure of the crystal. Classifying rimey crystals as a distinct group is sort of like lumping all molting birds into a distinct group. But just as Nietzsche  observed that histories reveal almost as much about the historians who wote them as about actual past events, I’d speculate that classification systems tell us a bit about the people who developed them as well as the subjects being classified. Maybe rime was important to Magono or Lee…

Source: http://www.storyofsnow.com/blog7.php



Actions

Informations

Leave a comment

You can use these tags : <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>