Objects moving across the water surface produce a V-shaped pattern, known as the Kelvin Wake pattern. The inside of the V is filled with transverse curved waves, (each of which is an arc of a circle centered at a point lying on the path at a distance twice that of the arc to the wake source) these transversal waves are often obscured by interferences like propeller wash, and tail eddies behind a boat’s stern.
Phytoplankton bloom captured by Envisat
The phytoplankton bloom pictured in this Envisat image stretches across the Barents Sea off the coast of mainland Europe’s most northern point, Cape Nordkinn. Although most types of phytoplankton are individually microscopic, the chlorophyll they use for photosynthesis collectively tints the colour of the surrounding ocean waters.
This allows for these tiny organisms to be detected from space with dedicated ‘ocean colour’ sensors, such as Envisat’s Medium Resolution Imaging Spectrometer, which acquired this image on 17 August 2011.
Photo Credit : ESA/Envisat
Great Sandy Strait estuary, Hervey Bay, Queensland, Australia.
From the NASA Earth Observatory
Von karman vortices forming in the cloud layer in the wake of the island of Guadalupe, Baja California.
von Karman vortices form nearly everywhere that fluid flow is disturbed by an object.
Image from Nasa Earth Observatory
Chao Hu is one of the five largest freshwater lakes in China. Heavy use of the lake in recent years has led to eutrophication and silting. Due to China’s rapid economic growth, the lake is now one of China’s most polluted lakes.
Picture by Jianan Yu / REUTERS
Yukon river delta, Alaska.
Photograph by Jay Dickman
To solve the fire protection regulations in the open-plan structure of the Mercedes-Benz Museum, a unique smoke elimination system was developed: an artificially generated tornado.
In the event of a fire, outlets located along the core walls inject air into the interior courtyard of the Museum generating an artificial tornado which collects the smoke and then discharges into the outside air.
Pictures of a stream of sandy water runoff, straight out of a snowfield at 2500 m by Sylvain Meyer. The melting snow mixes with the sand warmed up by the sun.