Von Kármán and plankton: Vortices captured in the sky and sea

Two prime examples of fluid dynamics were captured from above earlier this year in a remote part of the far north.

Seen in July, south of Norway's Svalbard archipelago, NASA satellites caught the simultaneous events in the air and ocean with von Kármán vortices above, and a colourful swirling plankton bloom below.

Von Kármán vortices form when air masses have to flow around towering obstacles, as is the case with Bear Island which has a highest elevation point of over 1,700 metres.

In the process, the air swirls downstream of the islands and forms counter-rotating vortices at the edges of the wind shadow zones created by the mountains.

These disturbances of the air currents are also transferred to the clouds, where they become visible as vortex structures.

Meanwhile, colourful phytoplankton blooms flowed in the ocean currents of the Norwegian and Barents Sea close by.

Phytoplanktons are microscopic organisms which like land plants absorb carbon dioxide and release oxygen. In isolation, their presence is not a negative sign, but large blooms can block sunlight from reaching ocean life living in their shadow below.

A bloom can last days or weeks depending on how long their source of nutrition sustains their growth. Once a bloom consumes all the available food, the plankton die and sink below the surface.

When viewed from above their appearance can also help highlight eddies and currents of the area they are in.