Jewel-toned waters swirled in the Pacific Ocean off the Chilean coast on November 10, 2009. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite took this picture the same day. Blue-green-hued water appears both north and south of Punta Lavapié.
Blooms of phytoplankton—tiny, plant-like marine organisms that thrive in nutrient-rich cold water—color the ocean water. A recent wind event in the region might have stirred nutrients, making such a bloom more likely. The chalk-like scales that cover a kind of phytoplankton called coccolithophores could account for some areas of brighter color. Although suspended sediment can also lend ocean water a pale hue, the continental shelf in this region is steep, leading to deep water just off the coast, and so the pale blue-green tones in this image probably don’t result from sediment.