On the afternoon of December 31, when NASA satellites flew through East Asia, near jeju island in the south of South Korea, the clouds were found distorted into strange shapes — spiral clouds twisted with each other, forming a "sky eye" shape like an eye, and like some exotic wind pattern, which looked quite special.
In addition to NASA's satellites, satellites from the Korea Meteorological Agency also captured a series of "sky eye" structures near Jeju Island, south of South Korea, on the afternoon of December 31. So what is this particular cloud? From time to time seismic clouds? There may also be many netizens who have heard about it, which is a special fluid phenomenon "Carmen Vortex Street".
Carmen vortex street (von Kármán vortex street) is an aerodynamic term, refers to the fluid placed in the blocking fluid, under certain conditions there will be unstable boundary layer separation, the two sides of the downstream of the obstructive fluid, will produce two asymmetrically arranged vortexes, one side of the vortex rotates in the clockwise direction, the other vortex rotates in the opposite direction, the two rows of vortexes are staggered with each other, each vortex and the opposite two vortexes of the middle point alignment, such as street lights on both sides of the street road, so the name vortex. In 1912, the physicist Theodore von Kármán first described this phenomenon, hence the name.
South of South Korea, this peculiar swirling cloud system is due to the mountainous terrain on jeju island in southern Korea as a blocking fluid in the atmosphere, and the flowing air rotates alternately downstream and eventually forms a series of swirls in the clouds.
According to Carlos Torres of Baja California Autonomous University, the pattern of the whirlpool depends on the intensity of the wind. Eddies are driven by prevailing winds, which change with the seasons and cause differences in the direction and structure of the eddy currents, but in general, it is a very common phenomenon. In addition to Jeju Island in South Korea, this phenomenon also occurs in the eastern Pacific Ocean, the Atlantic Ocean and other regions.