Can't help but think about flocking behavior and different physics issues I've programmed when I look at things like this. It's really interesting to watch the current change over time as well. Then think about the currents at different dimensions of the ocean knowing that they may be crossing currents at different depths.
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Perpetual Ocean: A Van Gogh-Like Visualization of our Ocean Currents
Goddard Space Flight Center Scientific Visualization Studio, which produced this three minute animation called Perpetual Ocean.