Spiral of Plankton (2)

A plankton bloom acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite, off the coast of Australia.

While the northern latitudes are bathed in the dull colors and light of mid-winter, the waters of the southern hemisphere are alive with mid-summer blooms.

Spiral of Plankton (1)


The eddy is centered at roughly 40° South latitude and 120° East longitude, about 600 kilometers off the coast of Australia in the southeastern Indian Ocean, as it appeared at 1:05 p.m. local time on December 30, 2013.

Like land-based plants, phytoplankton require sunlight, water, and nutrients to grow. Sunlight is now abundant in the far southern latitudes, so nutrients are the limiting variable to phytoplankton growth. Open waters of the ocean can appear relatively barren compared to the nutrient-rich waters near the world’s coasts. In the case of the bloom above, the nutrients may have been supplied by the churning action of ocean currents.

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