Theodore von Kármán, a Hungarian-American physicist, is well-known within NASA for helping found the Jet Propulsion Laboratory. But in atmospheric science circles he is most celebrated for his research on fluid turbulence and his pioneering work on a phenomenon that came to be known as von Kármán vortices.
Von Kármán vortices appear as long linear chains of spiral eddies and can develop nearly anywhere that fluid flow is disturbed by an object. The atmosphere behaves like a fluid, so the wing of an airplane, a bridge, and even an island can cause the vortices to form.
In this image, remote Bear Island (also called Bjórnóya)—the southernmost island of Norway’s Svalbard archipelago—helped trigger the spiraling cloud pattern. At the same time, another visually stunning phenomenon peeked through a break in the clouds: the tendrils of a phytoplankton bloom circulating in the surface currents of the Norwegian and Barents Sea. The MODIS (Moderate Resolution Imaging Spectroradiometer) on NASA’s Aqua satellite acquired the image on July 13, 2023.
Despite the name, polar bears only occasionally visit Bear Island. A handful of staffers at a meteorological station are the only people who spend much time on the island.
Foxes, seals, and sea birds are more common and numerous than either people or bears on the small island. According to the Ramsar Sites Information Service, more than one million seabirds gather there during the breeding season. Among them are the black-legged kittiwake (Rissa tridactyla), pink-footed geese (Anser branchyrhynchus), and the barnacle goose (Branta leucopsis).
References & Resources
- The Cornell Lab All About Birds. Accessed November 22, 2023.
- NASA Jet Propulsion Laboratory Dr. Theodore von Kármán (1881-1963). Accessed November 22, 2023.
- NASA Various Views of von Karman Vortices. Accessed November 22, 2023.
- Polar Bear Science (2019, July 31) Polar bear spotted on Bear Island (Barents Sea) this winter for the first time in 8 years. Accessed November 22, 2023.
- Ramsar Sites Information Service Bear Island. Accessed November 22, 2023.
- Science Direct (2023, November 22) Karman Vortex Street. Accessed November 22, 2023.
- Svalbard Børnøya Meteo (Bear Island weather station). Accessed November 22, 2023.
- Weather Underground (2023, November 22) Whirls, Curls, and Little Swirls: The Science Behind Von Karman Vortices. Accessed November 22, 2023.
NASA Earth Observatory image by Wanmei Liang , using MODIS data from NASA EOSDIS LANCE and GIBS/Worldview . Story by Adam Voiland .
