A study published in Science in June 2025 reveals a striking transformation in ocean color: Waters are becoming greener near the poles and bluer toward the equator. This shift reflects changing concentrations of chlorophyll—a green pigment produced by phytoplankton, the microscopic algae that form the foundation of marine food webs. Led by researchers from the Nicholas School of the Environment, the team analyzed satellite data from 2003 to 2022, collected by a NASA instrument. They found that chlorophyll levels are rising in polar regions while declining in tropical and subtropical zones. These trends suggest a redistribution of phytoplankton, which could have significant implications for global fisheries and the ocean’s role in carbon storage. READ MORE.
Photo of ocean wave by Matt Hardy.