Reminiscent of the distinctive swirls in a Van Gogh painting, millions of microscopic plants colour the waters of the North Atlantic with strokes of blue, turquoise, green, and brown. Fed by nutrients that have built up during the winter and the long, sunlit days of late spring and early summer, the cool waters of the North Atlantic come alive every year with a vivid display of colour. The microscopic plants, called phytoplankton, that give the water this colour are the base of the marine food chain. Some species of phytoplankton are coated with scales of calcium (chalk), which turn the water electric blue. Chlorophyll and other light-capturing pigments in others give the water a deep green hue. The proliferation of many different species in various stages of growth and decay provides many nuances of colour in this concentrated bloom. The bloom stretches across hundreds of kilometres, well beyond the edges of this photo-like image. The upper left edge of the image is bounded by Greenland. Iceland is in the upper right. Plumes of dust are blowing off the island, probably adding nutrients to the surface waters to its south.
Norman Kuring
<a rel="nofollow" class="external text" href="http://earthobservatory.nasa.gov/IOTD/view.php?id=7830">NASA Earth Observatory</a>