An analysis of satellite data reveals ocean waters are becoming greener at the poles and bluer toward the equator. The color change reflects shifting concentrations of a green pigment called chlorophyll made by phytoplankton, which are photosynthetic marine organisms found at the base of the ocean food chain. “In the ocean, what we see based on satellite measurements is that the tropics and the subtropics are generally losing chlorophyll, whereas the polar regions — the high-latitude regions — are greening,” details first author Haipeng Zhao, a postdoctoral researcher of the study.
