One of the most fascinating things about planet Earth is the way that life shapes the Earth and the Earth shapes life. We only have to look back to the Great Oxygenation Event (GOE) of 2.4 billion years ago to see how lifeforms have shaped the Earth. In that event, phytoplanktons called cyanobacteria pumped the atmosphere with oxygen, extinguishing most life on Earth, and paving the way for the development of multicellular life.
Early Earth satisfied the initial conditions for life to appear, and now, lifeforms shape the atmosphere, the landscape, and the oceans in many different ways.
At the base of many of these changes is phytoplankton.
The eddy imaged here likely peeled off from the Agulhas Current, which flows along the southeastern coast of Africa and around the tip of South Africa. Agulhas eddies tend to be among the largest in the world.
The image below shows the eddy in context with the surrounding area:
MODIS (or Moderate Resolution Imaging Spectroradiometer) is a key instrument aboard NASA’s Terra (EOS AM) satellite. Terra MODIS views the entire Earth’s surface every 1 to 2 days, acquiring data in 36 spectral bands. These data improve our understanding of global dynamics and processes occurring on the land, in the ocean, and in the lower atmosphere.