The topographic effect of the Prince Edward Islands in the predominantly eastward flowing currents of the southwestern Indian Ocean along with input of nutrients from the volcanic soils of the islands themselves and significant runoff of seabird and seal guano in the abundant local rainfall often results in a down-current plume of relatively high chlorophyll concentrations.
Farther north, the higher chlorophyll associated with the Agulhas Return Current is visible. North of that a cyclonic, cold-core eddy stands out from its low chlorophyll surroundings.
The Japanese island of Hokkaido may have still been largely snow covered, but the surrounding ocean was blooming on April 3, 2009. The cold Oyashio current flows past the island bringing a rich nutrient supply from the north which feeds phytoplankton powered by the spring sunshine. The warm Kuroshio Current collides with the Oyashio near the bottom right of the above image and both turn eastward to become the North Pacific Current.
Filamentous green swirls fill the northern Arabian Sea in February 2015. Recent research in the area has found that while winter blooms used to be dominated by diatoms, they are now largely composed of dinoflagellates -- a change that may have significant effects on the food web.
The patchiness exhibited by phytoplankton communities around New Zealand in this image provides the raison d'être for satellite remote sensing of ocean color; a whole fleet of ships, drifters, gliders, and buoys could not capture this variability before it morphed into a new pattern.
This image was collected by VIIRS image collected on September 30, 2015.
Recent work suggests that diatoms predominate during May in the Barents Sea while coccolithophores bloom in August. This MODIS scene, collected on July 10, 2014, may show those arctic waters in transition between greener diatom-dominated and milkier coccolithophore-dominated waters.
Ocean colors in the above image represent remote-sensing reflectance in the red, green, and blue portions of the spectrum. Green and blue reflectances have been scaled the same way, but the red reflectance has been scaled brighter to accentuate differences in this relatively dark portion of the spectrum. (Note that positive identification of phytoplankton species is not possible from these data alone; sea-surface sampling would be required for that.)