Please Register or Log in to view the hidden image! Please Register or Log in to view the hidden image! Please Register or Log in to view the hidden image! Please Register or Log in to view the hidden image! Please Register or Log in to view the hidden image! The highest clouds in our atmosphere. Appearing electric blue, most of these clouds are formed near the mesopause and some of their counterparts, another mesospheric cloud, noctilucent clouds, appear near the stratopause. Please Register or Log in to view the hidden image!
http://www.ball.com/aerospace/media/images/aim_clouds_1.jpg ^^ that pic is exceptionally beautiful Please Register or Log in to view the hidden image!
No. Nacreous Clouds are stratospheric clouds when cold tropopause air is carried up my high surface winds and clashes with the bitter, dry, warm air of the stratosphere. They're also called PSC's or Polar Stratospheric Clouds, but shine electric yellow or bright orange because of the sun, not the highest clouds though. PMC's or Polar Mesospheric Clouds have a smokey look, while PSC's also called Mother Of Pearl Clouds look like a typical cirrostratus or some kind of rough smoke... or at least I think. Im a bit rusty at clouds. Heres a picture of Nacreous. Please Register or Log in to view the hidden image!
Meaning that they form because the stratospheric air grows warmer - not cooler? Are there any solid particles involved as nuclei? When the Earth was in its snowball episodes - late Precambrian time - these might have been the only clouds which could form...
That could've been a brilliant sight. Mock suns, and nacrous clouds everywhere, wow, now imagine that.
I dont remember but those lights are very bad for the atmosphere. It may be pretty but i dont remember what it does ill have to do some research but i know its no good for the earth.
I don't see how those lights can have a negative impact on the atmosphere ... it is just light. And anyways, PMC's don't really effect surface weather patterns except for maybe blocking out extra solar energy at the mesopause level. As far as I know, those clouds and the resulting light emitted are harmless.
An unbroken layer over the polar regions? That might augment the high albedo of the glaciers, leading to global cooling. As you said about the Snowball Earth phase, it could look pretty spectacular as well. Forget the aurora borealis...