Phytoplankton Bloom off Coast of France48.7N 6.2W
Colorful phytoplankton blooms, such as this one in the Atlantic Ocean off the northwest coast of France and the southwest coast of England, are complex phenomena created by a phytoplankton population explosion.
Such a bloom-creating explosion occurs when sunlight and nutrients are readily available to the plants, reports the UNH Coastal Observing Center, causing them to grow and reproduce to a point where they are so dense that their presence changes the color of the water in which they live.
Blooms can be quick events that begin and end within a few days or they may last several weeks. They can occur on a relatively small scale or cover hundreds of square kilometers of the ocean’s surface.
Factors that influence where and when phytoplankton blooms occur include water temperature, density, and salinity, hydrography of the region, availability of nutrients, what species and the amount of phytoplankton biomass that is present, what types of zooplankton are grazing on the phytoplankton, and available sunlight levels.