Phytoplankton Bloom in the Baltic Sea

Cyanobacteria bloom in the Baltic Sea 2015On August 11, 2015, the Operational Land Imager (OLI) on Landsat 8 captured this false-color view of what appears to be a large bloom of cyanobacteria swirling in the Baltic Sea south of Gotland.
 
Cyanobacteria (or sometimes blue-green algae) are an ancient type of marine bacteria that, like other phytoplankton, capture and store solar energy through photosynthesis. Some are toxic to humans and animals. Moreover, large blooms can cause an oxygen-depleted dead zone where other organisms cannot survive.
 
Read more: NASA Earth Observatory - Blooming Baltic Sea.