ASPERITAS, The CAS Cloud
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A separate thread on, for and about the CAS identified cloud now officially known as ..Asperitas,,thanks to our founder Gavin Pretor-Pinney,strikes me as worthy of a try. Photos would be my main contribution. I live in Phoenix Az, the Upper Sonoran Desert.We have around 275 days a year of ..blue sky. When we do have weather it tends to be quick in passing.At a very local place, my house,,a good rain is one that lasts half an hour. So the systems rush through with much hurly burly. That speed and energy tends to create Asperitas somewhere in the Valley as a system passes through. I enjoy the challenge of spotting the phenomena.
Asperitas at dawn
A Close Up
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Thanks Michael, for the initiative to give asperitas its own topic on the forum in a great start. It is only one month and two weeks ago that Geoff LB reported that asperitas has become mainstream. That might be in the sense of common knowledge, but not in the sense of its appearance.
I hope for a lot of different contributions and I hope you don’t want too limit it to only clear cases, Michael. There are also cases where one doubts whether it is asperitas or not. There are so many different kind of appearances that they are worth to discuss imho. For instance your recent ‘half half” on the Colour Thread IV (which I think it is).
What to think of this one. Is this asperitas giving the eye?
Any opinions?
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So far Hans, I’ve seen Asperitas Undulatus, Laconusus, and Radius here,with undulatus the most common. In any case, there has to be enough to hang your hat on. Your shot offers Undulatus yet Im not seeing Asperitas. For Aperitas I think in terms of a field or large area where redundant waves of of agitation are seen. Looking at the clouds upside down for verifying ,,needs larger sampling to see the waves.
Below is shot of what I call”Speckled Asperitas.” Light making it through the clouds to freckle their appearance adds even more to these surreal clouds…imho.
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Michael, I agree your Speckled Asperitas is a beauty. I assume the layer of clouds is relatively thin?
I agree also with the analysis of the asperitas giving the eye. This was more a cut-out with some interesting features (to me). Here is larger sampling that shows a lot of lenticulars but with irregular undulating in it. I am curious what your opinion is on a wider view.
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Thank you for launching this great topic, Michael! It’s off to a splendid start already and should draw many contributors who enjoy the rollercoaster rides of Asperitas. Wouldn’t be surprised if this calls for dramamine!
And Hans, the images you’ve posted so far have much of the feeling I associate with Asperitas, so regardless of whether or not they meet classification parameters, they are exciting to see here.
I haven’t see many instances of Asperitas locally, so hope a repost of one of my favorites is acceptable here. You and Hans might recognize a portion of it as The Mermaid’s Tresses from one of the B&W volumes.
Asperitas Over San Francisco Bay -
Michael: unfortunately no wider view of my suspect. Indeed a lot lenticular. What makes it a bit asperitas-like for me are the irregular waves so typical for asperitas. I conclude: coincidence in a lenticular undulating scenery. It just lasted less than half an hour I remember.
Keelin: that is a fantastic picture over Francisco Bay! The day it got published I complemented you with it on the gallery. I also saw your picture not so long ago in one of the Somewhat Occasional Newsletters from CAS. It is a surprise you took from this the mermaids tresses. Wonderful.
Just today we had an asperitas event in the midst of some weather changes. No doubt about this one imho. I have a series in which one can see loose patches of asperitas and also phases of dissipating.
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Michael, Hygge is pleased with your initiating this thread, not least for the marketing of CAS. And I think you have asperitas to the T in your photos.
Hygge has never observed asperitas, but I seem to remember one photo in nearby Dorset, UK, so no excuses.
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Thanks hygge!, I hope you witness Asperitas soon. It seems to me, if there are two layers of cloud overhead that improves the chances of Asperitas. Of course one can’t see two layers if the lower one is not transparent enough. Big Sky gives an advantage because if the upper layer ,say a alto stratus, is expansive enough the lower layer takes up only a portion of the sky in comparison , again making it easier to spot the phenomena. Its always easier to identify Asperitas from a distance than when its overhead. When its overhead its more difficult to identify the ” roll” of the waves, the peaks and valley of the wave action. At a distance just look at it upside down and you will know. I love the look on folks’ face when they do look at Asperitas upside down..” oh wow, now I see It!”
Arizona Asperitas#105
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Nice knowing about the layers Michael. I checked my series of yesterday. Here is a overview of patches of asperitas on a lower layer and somewhat higher there seems to be a stratus layer.
Oh and yes, I agree asperitas is better recognized looking form an angle than overhead. Overhead they don´t betray their forms so easy while looking at an angle the shapes and shadows give them their special appearance.
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Yes,Lighting is so critical to Asperitas. It helps to have some making it thru the clouds imho. I’ve learned to shoot Asperitas somewhat flat,,that is to say,,not with contrast dialed up. Details in the shadows get lost very easily with Asperitas. Dial down the contrast will get the details in the shadows and when I process the picture, I control how much contrast I bring back to the photo.
Arizona Asperitas#106
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I agree Michael, too much contrast might spoil details. It is a matter of fine tuning.
I am getting spoiled over here. After my former asperitas event even two times yesterday. Too much to share at once. The second appearance of asperias made me think of he rather lenticular situation I posted above. To test the statement by Michael about hardly recognizing asperitas overhead versus asperitas seen at a lower angle, I made these two shots (among others).
Overhead
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Nice streets on #112 Michael. Too much boring blue skies over here too Keelin.
Next one is one of my first encounters from the archives. It was a nice summer day with a lot of people going to the beach. At the moment I took this picture a lot were already gone or busy fleeing, while I was enjoying this dramatic sky with a hint of asperitas in it coming from the sea foreboding a change of weather.
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Yes I had Michael. Particularly the day that started with asperitas and gradually became lenticular with exploding Holmboe and all kinds of strange lenticular-like shapes like a Chicken Abductee or a Talking Sorting Hat. It took from 9:00 until 11:15. On the gallery I posted two pics of the same scenery taken with an hour in between on which you can see the two different phases.
Asperitas Phase
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Fronts either coming in or retreating sometimes provide for the multi-layers of wind not all going in the same direction..which produces great displays as the orientation of wind direction changes over the day. You captured a pretty neat day Hans!
Another shot showing the physics that produce Asperitas, existing over two sets of cloud.
Arizona Asperitas #129
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Yes, you are right Michael, it was a pretty neat day. The show lasted three or four hours. The asperitas was followed in that timeframe by lenticular formation with seemingly some asperitas characteristics leftover. I posted some of those in the Color Thread, for example my favorite ‘Cloudshow’, ‘Soft Clouds’ and the ones with Holmboe. Ever seen something like Cloudshow?
Nice to see two sets of clouds with asperitas on your Arizona Asperitas #129.
Asperitas Phase #2
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Asperitas Over San Francisco Bay
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