Research published in the journal Biogeosciences examines the chemistry behind an annual algal bloom and the algae that cause it ─ tiny, single-celled photosynthesizers called coccolithophores that are neither plants nor bacteria. Their microscopic swarms, shown in this NASA satellite image, dominate the Great Calcite Belt, a ring around the Southern Ocean so large it can be seen from space.

As explained by LiveScience, “Coccolithophores cover their bodies in plates of chalk (calcium carbonate) as they grow. When they concentrate together in the ocean, that chalk reflects light back into the sky, giving the water a milky-blue color.”

The research performed during two one-month cruises in the Southern Hemisphere in 2011 and 2012 analyzed the ecological scenarios that allow coccolithophores to thrive, such as competition with other phytoplankton and reduced amounts of silica. It also assessed the role of coccolithophores in the global carbon cycle as they use carbon to build their shells and release carbon dioxide in the process.

Read more at LiveScience.

Image credit: NASA