Nasa's Aqua satellite has captured pictures that show something unusual about Iran's lake Urmia. The lake which was green a couple of months ago has suddenly turned into bright blood red color.
NASA's (MODIS) instrument on the Aqua satellite has sent back satellite images of the Lake Urmia captured on July 18 which show the water in the lake turned red in color, reported Daily Mail.
What's more interesting to note is that the water in the Lake was green in pictures taken on April 23. This means that the transition from green to red color has happened in mere three months' time. The shoreline in the picture is encrusted with salt deposits and appears white in color.
According to the NASA experts, microorganisms might be the reason behind the change of color. They are suspecting that the bacteria family called Halobacteriaceae and the algae family Dunaliella have caused Lake Urmia's water to turn into deep red color. It is during summers that the water levels in the lake drops and the salinity level increases. In conditions of high salinity, these bacteria release a red pigment called bacteriorhodopsin that absorbs light and converts it into energy for the bacteria. When bacteria populations are large enough, they can stain a whole body of water.
Mohammad Tourian, a scientist at the University of Stuttgart, said that Dunaliella salina is responsible for reddening of Lake Urmia. He added that Dunaliella salina appears green in the marine environment. But, in conditions of high salinity and light intensity, the microalgae turns red due to the production of protective carotenoids in the cells, reported Nature World News.
While Lake Urmia turning red from green is a temporary change and the same has happened several times in recent years, NASA has noted the possibility of Lake Urmia turning permanently red as Iran's drought increases.