NASA captures turquoise plankton blooms in Black Sea

ISTANBUL

In a striking display of the planet’s living canvas, the National Aeronautics and Space Administration (NASA) has captured the normally dark waters of the Black Sea spun into glowing, turquoise ribbons by an explosion of microscopic marine life.

The color shift stems from a massive surge in coccolithophores, single-celled marine organisms coated in microscopic calcium carbonate plates. As these populations multiply by the billions during late spring, their reflective shells turn the sea surface into a milky blue landscape.

The phenomenon extended directly into the Bosphorus, the heavily trafficked waterway connecting the Black Sea to the Sea of Marmara. An Expedition 74 astronaut aboard the International Space Station photographed the strait using a Nikon Z9 camera on May 27, documenting striking turquoise patterns swirling alongside strong marine currents. Concurrently, NASA’s PACE satellite acquired the broader Black Sea imagery using an Ocean Color Instrument(OCI) on June 22.

During other periods of the year, silica-shelled diatoms dominate the basin, absorbing different wavelengths of light and giving regional waters their characteristic dark hue. Researchers depend heavily on such orbital imagery to monitor these massive ecological shifts, particularly in expansive marine zones where gathering physical water samples remains a logistical challenge.

Beyond altering the ocean’s surface appearance, coccolithophores drive a critical component of the global carbon cycle. These organisms pull carbon from the atmosphere and seawater as they grow, eventually dying and sinking to the ocean floor, where they safely store the trapped carbon for extended periods.