From Time Machine
Derived from the Aqua MODIS satellite by NASA Goddard Space Flight Center, this dataset documents chlorophyll concentrations in the oceans from June of 2002 through July of 2011.
Chlorophyll concentrations in the ocean primarily indicate plankton growing. Observe the seasonal shifts between summer in the northern hemisphere to summer in the southern hemisphere 6 months later.
The imagery here represents a rolling 32-day composite, meaning each frame of the animation is a composite of 32 successive days of data from the Aqua MODIS satellite.