English: 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.