Skip to comments.Astronomy Picture of the Day -- Asperatus Clouds Over New Zealand
Posted on 02/27/2013 4:08:27 AM PST by SunkenCiv
Explanation: What kind of clouds are these? Although their cause is presently unknown, such unusual atmospheric structures, as menacing as they might seem, do not appear to be harbingers of meteorological doom. Known informally as Undulatus asperatus clouds, they can be stunning in appearance, unusual in occurrence, are relatively unstudied, and have even been suggested as a new type of cloud. Whereas most low cloud decks are flat bottomed, asperatus clouds appear to have significant vertical structure underneath. Speculation therefore holds that asperatus clouds might be related to lenticular clouds that form near mountains, or mammatus clouds associated with thunderstorms, or perhaps a foehn wind -- a type of dry downward wind that flows off mountains. Such a wind called the Canterbury arch streams toward the east coast of New Zealand's South Island. The above image, taken above Hanmer Springs in Canterbury, New Zealand, in 2005, shows great detail partly because sunlight illuminates the undulating clouds from the side.
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[Credit & Copyright: Witta Priester]
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“What kind of clouds are these?”
Really, really ticked off clouds. You can see almost a fury, can’t you?
That is wild.
At first glance, I read “asparagus” clouds. Made me wonder if the rain smelled funny.
I’ve looked at clouds from both sides now!
Different eyes, different perspective. My 6 year old (before heading out for school) said, “why is there a monster in the clouds?” In the right corner, she saw a monster face. Very scary, Sunky!
Spectacular! Does not look real.
I wonder if they are filming the last Hobbit movie down there currently. Those are better than any CGI!
Those are Wrath-of-God, Biblical clouds. I wonder what New Zealand did to make them so angry?
What you are probably looking at is lenticular clouds that are being disrupted by thermals from the ground. As the hot air rises (it is turbulent) it meets the the laminar flow of upper air. This upper air is in waves. You can see it in the areas of the clouds that are smooth. These waves are formed by high speed air blowing across a mountain range. If you could see the top of those clouds they would be smooth and rounded.
We glider pilots live for mountain wave. You can go to great altitude in them. I have been to 25000 feet and this is not considered high for a mountain wave flight.
Thank you for that explanation.
I’ve been on top of the Big Southern Butte (in Idaho) when the hang gliders were catching the thermals coming up off the black rock lava formations called the Craters of the Moon.
And I’ve seen some great cloud formations and based my previous comment thusly.
That sky, anytime, haul a$$.