Though actinoform clouds were at first believed to be rare, satellite observations collected in the past few decades have actually made it clear that they are relatively typical. The clouds are regularly spotted in imagery of the ocean. They can last up to 72 hours and typically bring drizzling rain.
On March 11, 2022, the Visible Infrared Imaging Radiometer Suite ( VIIRS) on the NOAA-20 satellite recorded this image of two actinoform clouds to the west of Alejandro Selkirk and Robinson Crusoe islands. The cloud further to the east has a classic actinoform shape, while its partner to the northwest has a more direct, diffuse type.
It is unclear why actinoform clouds establish, however they appear where marine stratocumulus clouds occur– normally in stable air along the western coasts of major landmasses. Researchers think that ocean currents and water temperature levels play a role in their formation.
Other distinctive clouds were likewise on screen on March 11. Faint rows of von Kármán vortices appear north of the two islands. The spiraling cloud patterns form when winds get diverted around raised locations, often islands, rising from the ocean.
The two islands underneath the clouds are volcanic mountains off the coast of Chile. Alejandro Selkirk island was named after a Scottish sailor who spent four years as a castaway on the neighboring island after his captain abandoned him after an argument.
Alexander Selkirks (also spelled Selcraig) experience functioned as partial motivation for the novel The Life and Adventures of Robinson Crusoe. When called Más a Tierra, the smaller sized of the islands was renamed Robinson Crusoe in 1966 in honor of the book. At the very same time, Alejandro Selkirk island, formally called Isla Más Afuera, was offered its name.
NASA Earth Observatory image by Lauren Dauphin, using VIIRS information from NASA EOSDIS LANCE, GIBS/Worldview, and the Joint Polar Satellite System ( JPSS). Story by Adam Voiland, with info from Michael Garay (NASA Jet Propulsion Laboratory).
The centers of “closed” cells were clouded over, while “open” cells had clear. Actinoform clouds were initially believed to be rare, satellite observations collected in the previous couple of decades have actually made it clear that they are relatively common. The clouds are regularly spotted in imagery of the ocean. Other attractive clouds were likewise on screen on March 11. The spiraling cloud patterns form when winds get diverted around elevated locations, typically islands, rising from the ocean.
March 11, 2022. (Click image for high-resolution, wide-field view.).
Two captivating cloud types– flower-shaped actinoform and spiraling von Kármán vortices– appeared off the coast of Chile in March.
Some of the first features that researchers discovered in April 1960 after NASA launched TIROS-1, the very first weather satellite, were strange hexagonal “cells” that appeared in clouds over the ocean. With diameters varying from 50 to 100 kilometers (30 to 60 miles), the features were big enough that they had actually never been recognized from the ground.
The centers of “closed” cells were clouded over, while “open” cells had clear.
