![]() ![]() One recent hypothesis: it’s formed when an oscillating motion from an atmospheric gravity wave or instability occurs within a highly-layered region of a cloud. But even though it has the WMO stamp of approval, meteorologists are unsure about what exactly causes asperitas. Nonetheless, cloudspotters lobbied for its classification and it was officially recognized in 2017. “I was a bit defeatist about it ever becoming official,” he admits. In 2008, Pretor-Pinney first told scientists at the UK Royal Meteorological Society about it in a BBC documentary, but he didn’t think about pushing for it to join the Atlas. Here, Pretor-Pinney tells us how to identify the 12 newly-recognized clouds, including the one he considers “the jewel in the crown” of the skies.Īsperitas, which means roughness in Latin (every formation in the Atlas has a Latin name), is considered a supplementary feature, a WMO designation which means the bumpy formation shows up only in part of a cloud and not the entire cloud (such as in the case of varieties). Despite their ephemeral nature, clouds in the Atlas follow a rigid classification system that starts with ten genera, or general cloud types (e.g., cirrus, cumulus), then falls into 15 species, marked by differences in shapes and internal structures, and then is divided further into nine varieties, which describe their level of transparency and visible arrangements. In March 2017, Pretor-Pinney played a role in expanding the vocabulary of clouds when asperitas, a formation that he was the first to bring to public attention, was included in the most recent edition of the International Cloud Atlas, the official list maintained by the World Meteorological Organization (WMO). “Clouds are the ever-present backdrop to human culture,” he says, affecting the weather, climate and creative imagination. As an ardent amateur cloudspotter and the founder of the Cloud Appreciation Society, the UK-based Pretor-Pinney spends much of his time gazing at clouds, those suspended particles of liquid water and/or ice that are, he says, an intrinsic part of our existence on Earth. Cloud Appreciation Society founder Gavin Pretor-Pinney introduces us to them and to the wild and wonderful world above us.įor Gavin Pretor-Pinney, hell might be someplace like Yuma, Arizona, said to be the sunniest city on Earth and boasting more than 4,000 blinding hours of sunshine a year. Can you tell your cavum from your cauda? Your homogenitus from your homomutatus? Those four cloud formations, along with eight others, have been added to the International Cloud Atlas, the official compendium of all things cloud.
0 Comments
Leave a Reply. |