Every summer, as the ice melts, the waters of the Chukchi Sea off the Alaskan coast come alive with phytoplankton blooms. In satellite images like this one, they can look like abstract paintings formed from swirling colors. In the Chukchi Sea, two main currents collide. One, water from the Bering Sea, is cold, salty, and nutrient-rich. This is the preferred home to phytoplankton known as diatoms, which are responsible for some of the greenish hues seen here.
Coccolithophores, another variety of phytoplankton, prefer the warmer, less salty Alaskan coastal waters. Despite a relative lack of nutrients, the coccolithophores thrive, creating the milky turquoise color seen in the image. Knowing these characteristics of the phytoplankton, observing the growth of blooms over time may tell scientists about how the flows in these areas shift and change from year to year. (Image credit: NASA; via NASA Earth Observatory)