High Sierra Topix

I am just calling it Ice Grass, but on my last trip I notice a small 1.5'x1.5' area
in a grassy part next to the smaller Orchid Lake, where a smaller crystal city had
formed.
I have never before witnessed this, so I got down on my knees to inspect it closer
and to my surprise it was these ice blades 3"x1/8" in measurement.
Breaking off a blade just to make sure my eyes were not deceiving me I snapped
it in two, and quickly melted between my palms.
So how did these ice blades form, any hypothesis folks?
Has anyone else ever seen these ice grass formations here or any where else?
The even weirder thing is, if you look at the picture you will see dirt on the tips
of some of the blades, as though the came up from underneath the ground.
An hour later, after it warmed a bit, they had melted.
http://maverick.zenfolio.com/img/s9/v13 ... 6936-6.jpg" onclick="window.open(this.href);return false;

Maverick,

That's an easy one! It is a form of hoar frost. Basically this photo is of surface hoar. As I recall it forms when water vapor moves out of the earth when air temp is below freezing. It is common in damp areas of trails, especially in the fall and spring. I bet you saw it on Monday, on the clear morning after the stormy weekend. I saw some as I walked x-country from the w. end of 1000 Is. lake toward island pass. This may be heresy but I love walking on it and feeling the crunch under my feet.

A similar phenomenon occurs on snow crusts. Rather than coming out vertically it is in the form of small delicate sheets/flakes of ice that really glisten in the low light of early morning.

Mike

Well thank you OR for the quick explanation, hoars frost, interesting.

I asked my Dad because like all Dad's he is practically an encyclopedia LOL. Anyway, here is his response...

Hi Squidlo:
That is really cool. I think its called needle ice and your right it requires water at or near the surface. The water is obviously liquid under the ground and hydrostatic force pushes it up. As it gets to the surface it freezes and is continuously pushing up more as ice. The following website explains it. And the one below is another picture of it.

http://www.sierrapotomac.org/W_Needham/ ... 070123.htm" onclick="window.open(this.href);return false;




http://nsidc.org/frozenground/how_fg_affects_land.html" onclick="window.open(this.href);return false;

Thanks Sblase, and thank your Dad, and welcome to HST!

A cool photo and some great explanations. Now I want to try to get a time lapse of these forming!

Thanks for that link sblase. Have seen that often along the Eastern Sierra in wet areas when nightime temps regular dip below freezing. I also enjoy photographing the below phenomenon that occurs when the surface of puddled daytime water freezes overnight and then the water below the ice surface drains away before it can freeze. That leaves a hollow plate of ice often with interesting curving patterns. As a kid/adult , also enjoy stepping on hollow ice mud puddles that make a fine crackling sound.

http://www.davidsenesac.com/Fall_2007/ice_leaves.jpg" onclick="window.open(this.href);return false;

I noticed this a few times. Once I saw it in several places near Ferguson Lake just off the tablelands. Here is the interesting thing. The first time I remember seeing this was ---Orchid Lake! Isn't that a coincidence.

Every fisherman sees this on a daily basis in the cold morning around the lakes. I have a pic i took of it on my last trip but it came out blurry: Your pic was much better, but it's the same process. crunch.. crunch.. crunch..

Interesting. I just saw this stuff for the first time over Labor Day weekend, near Pear Lake.

http://www.facebook.com/photo.php?pid=3 ... 1604262239" onclick="window.open(this.href);return false;