Volutus clouds are long, tube-shaped, and seem to rotate around the horizontal axis such that they look like they’re rolling. They’re the newly recognized species of cloud, but only occur in altocumulus and stratocumulus types (the ‘cumulus’ suffix means they’re both puffy). This stratocumulus volutus is unusual in that it has layers, much like ogres and onions, where normally it would be smooth and rounded. Christy Gray | International Cloud Atlas
Yes, there are 31 species of clouds—yes, they’re called species, just like plants and animals—in the new International Cloud Atlas. Bonus: there are also five new “supplementary features” recognized plus five “special clouds,” including the beautifully named flammagenitus, which sounds less like a localized collection of air moisture formed near wildfires and more like a wildly painful STD. And there’s a new accessory cloud, the flumen, which I can only assume is a small storage unit from Ikea (it’s actually a long, flat cloud associated with severe storms). But the pièce de résistance is the single new species: the volutus. Long, round, and rotating, in motion they look a bit like cloud hot dogs roasting on a spit. Only prettier.
Amusing as cloud names are, categorizing them is serious business. The World Meteorological Organization, a subsection of the United Nations, has spent years collecting data from around the world to put together the newest edition of the Atlas. And it’s not just a fun resource to look at lots of pretty cloud pictures—it’s also a reference tool. They’ve basically compiled a massive database of every cloud type along with key information about each image, such that professional cloud observers (yes, that’s a real thing) have an up-to-date source to reference.
It’s been published periodically since 1896, when it was an impressive feat just to have color photographs of the clouds, much less understand complex atmospheric science. Today we know far more about how clouds form and what weather they portend, so our classifications can be more complex. There are 10 overall types called genera, which are divided into different species—31 in all. Those 31 species can be further subdivided into several varieties, which describe the arrangement and visibility of the cloud parts.
So in honor of the 21st-century Cloud Atlas, here are some beautiful cloud pictures (and also some actual information):
Sara Chodoshis an associate editor at PopSci where she writes about everything from vaccine hesitancy to extreme animal sex. She got her master's degree in science journalism at NYU's Science Health and Environmental Reporting Program, and is getting a second master's in data visualization from the University of Girona. Contact the author here.