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[cloud appreciation society] If you’ve got something to tell us, we’d love to hear it. But only if it is about clouds. Otherwise we’re not interested.
Quote[cloudappreciationsociety.org] If you’ve got something to tell us, we’d love to hear it. But only if it is about clouds. Otherwise we’re not interested.http://cloudappreciationsociety.org/
[cloudappreciationsociety.org] If you’ve got something to tell us, we’d love to hear it. But only if it is about clouds. Otherwise we’re not interested.
Hi Neil,You clouds are:High, CirrusMiddle, AltocumulusLow, Cumulus.The one you have posted above is of a proposed new type of cloud, currently being called Asperatus. The classification of this cloud is currently being reviewed and discussed by the Met Office, and if they think it could, or should be classified as a new cloud type they will take it to the WMO for their approval. Exciting times...
yep, I heard about the new type of cloud........ but surely this type of cloud has been around since ...well..clouds have !
“Asperatus” clouds form when there are two (or more) layers of air of differing density, one sitting on the other. The cooler and higher layer is cloudy and the other layer is clear. The boundary between these layers may occasionally get knocked up, but will return downwards thanks to gravity and then may go further down but will return back up thanks to buoyancy. This creates a wave-like surface along the cloud base, and we call these gravity waves because the returning force is gravity and buoyancy.Yes, the waves on the surface of the sea are a good example of this process.Another good example is when moist air blows over a range of mountains and makes a system of mountain wave clouds. In New Zealand this often happens, and people in Canterbury call the mountain wave clouds “the northwest arch”.At first individual Altocumulus lenticularis clouds form, but as a front approaches, upper-level moisture increases and middle and high clouds combine to produce an arch cloud comprising Altocumulus, Altostratus, and Cirrostratus. This arch cloud displays a very sharp edge near the mountains and often there is an arch of clear sky immediately downstream of the mountain divide.We can cope with the current naming scheme and use Altocumulus lenticularis to describe the NW arch clouds, but it would also be useful to have the extra variety or species word “ASPERATUS” especially when there are undulations in the cloud base.