The World Meteorological Organisation has published the first new edition of its Cloud Atlas since 1986 and in so doing named eleven new types of cloud, some identified by digital-camera-wielding citizen cloud wonks.
The new edition is also the first to be published online.
The big new addition to the Atlas is “Volutus”, a new species of cloud the Organisation (WMO) describes as follows.
A long, typically low, horizontal, detached, tube-shaped cloud mass, often appearing to roll slowly about a horizontal axis. The roll cloud, volutus, is a soliton, not attached to other clouds and is an example of an undular bore.
A Volutus cloud. Copyright Michael Bruhn. Colossal image here
Clouds are classified according to a taxonomy that names genera, species varieties and supplementary features.
No new genera of cloud has been named in this atlas. But Volutus was named as a new species in genera Altocumulus, clouds that float between 2,000m and 6,100m above Earth and which the WMO says are “White or grey, or both white and grey, patch, sheet or layer of cloud, generally with shading, composed of laminae, rounded masses, rolls, etc., which are sometimes partly fibrous or diffuse and which may or may not be merged”.
Also new to the Atlas are five special features, namely “asperitas, cavum, cauda (often known as tail cloud), fluctus (widely known as Kelvin-Helmholz wave) and murus (known as wall cloud).”
“Asperitas was first identified with the help of citizen science, enabled by modern technology,” the WMO says.
That new technology is the digital camera which makes it far easier to snap clouds on the off-chance they're significant, and also far easier to share them with like-minded cloud-watchers. The WMO therefore thanks “meteorologists, photographers and cloud lovers from around the globe” as having contributed to the new edition. Their efforts helped the WMO to identify and name five new “special clouds”, namely “cataractagenitus, flammagenitus, homogenitus, silvagenitus and homomutatus.”
“Homogenitus” are clouds made by humans, and the type therefore encompasses contrails. “Cataractagenitus” describes the clouds that form near waterfalls while “flammagenitus” are the result of fire. “Silvagenitus” are clouds that form over forests while “Homomutatus” describes clouds that change due to human activity.
And in a pleasant irony, it looks like all that data is hosted in a public cloud. When your correspondent searched for the WMO's IP address, we came up with 22.214.171.124, in a block WHOIS tells us is owned by Amazon Technologies Inc. of Seattle. ®
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