The International Cloud Atlas has added twelve types of cloud formations to its recognised list for the first time in 30 years. The atlas has also broadened its horizons this time by adding a new “species” – the volutus, or tube-shaped “roll-cloud” and recognised clouds formed by fumes from aeroplane exhausts. The new edition has been made available online.

The International Could Atlas first came out with a list of recognised cloud formations in 1896. The last full edition was published in 1975 and revised in 1987. The last edition became a collector’s item, but the new edition has been made public in keeping with the times. The atlas is published by the World Meteorological Organisation.

The most celebrated new entrant on the list is the wave-like cloud formation called Asperitas (pictured above), which cloud watchers, especially citizen group Cloud Appreciation Society, have been lobbying for a while now. They were first recorded over Iowa, United States, in 2006.

“Back in 2008, I thought the chances of this becoming official were really minimal,” Gavin Pretor-Pinney, president of the society, told BBC. “At first the WMO were saying they had no plans to do a new edition, but over time I think they began to realise there is an interest among the public in clouds and there is a need for that interest to be an informed one, there’s a need for this authoritative work.”

Other additions include Cavum, also known as the hole-punch cloud; cauda, or tail cloud; mluctus; and murus, or wall cloud. The new list also recognises clouds formed from wildfires and gives them a name – flammagenitus. Besides clouds, the new edition also features a few weather conditions such as rainbows, halos, snow devils and hailstones.