photo #5449744

This seascape by nineteenth-century German painter Caspar David Friedrich helps shed light on one of the newest clouds to be added to the cloud classification system. Entitled Flat country shank at Bay of Greifswald and painted circa 1830-34, the scene on the Baltic Sea coast of Germany shows a turbulent Stratocumulus stratiformis sky with irregular wavy features now known as asperitas. In 2008, the Cloud Appreciation Society first proposed that asperitas should be considered a distinct cloud formation. It was eventually accepted as an official classification in 2017 when the World Meteorological Organization added it to their International Cloud Atlas, making it the first ‘new’ cloud formation to be added to the reference work in over 60 years.An example of citizen science in action, our case for asperitas to be recognised officially was supported by hundreds of images contributed by our global community of cloudspotters. A painting like Friedrich’s – one of two in which he depicted asperitas cloud features – helps confirm the formation itself is nothing new. All that’s new is our ability to spot it, thanks to an interconnected worldwide network of cloudspotters with smartphones.