Like a peacock spreading its tail, the Barents Sea dazzled with color in late August 2012. The swirls of blue, green, and teal were created by a phytoplankton bloom—a profusion of microscopic, plant-like organisms thriving in the seawater. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite acquired this natural-color image on August 24, 2012. It shows an area just west of Novaya Zemlya.
All phytoplankton need sufficient carbon dioxide, sunlight, and dissolved nutrients to bloom. Any given bloom can include a broad range of species, but different species dominate the seas under different conditions. A study published in 2009 found that in the Barents Sea, diatoms generally bloom each May, after winter and spring storms have mixed the ocean layers and brought up nutrients from the deep.
But MODIS took this picture in August. While diatoms dominate the Barents Sea in May, coccolithophore blooms proliferate during the calmer conditions of the late summer. Coccolithophores are phytoplankton with calcite plates—coccoliths—that look like tiny hubcaps. The calcite of coccolithophore blooms lends especially light hues to ocean water.
By August, the Barents Sea has settled into well-stratified layers with warmer, less dense waters lying on top of colder, denser waters. Blooms of Emiliana huxleyi, the predominant coccolithophore species in this region, occur in such highly stratified waters.