Algal bloom near Alaska. Satellite image of an algal bloom in the Bering Sea near Alaska's Pribilof Islands. Algal blooms are formed by the rapid multiplying of phytoplankton, microscopic marine plants that drift on or near the surface of the sea, sustained by sunlight. Blooms in the Bering Sea increase significantly in springtime, after winter ice cover retreats. Phytoplankton populations plummet over the summer. By autumn, storms can stir nutrients back to the surface and cooler waters make better bloom conditions. Image data obtained on 22 September 2014, by the Operational Land Imager (OLI) on the Landsat 8 satellite |