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This demo uses the product of Chlorophyll-a from the NASA-MODIS Aqua satellite. This sensor acquires data in several spectral bands, and many products are available for ocean surface. We are using monthly means since 2002.
When you click at any point in the ocean, the time series of this point is extracted and converted to music. The chlorophyll concentration defines the pitch of a note (in a C Major scale).
A curious sidenote: we discovered after implementing this method that Heitor Villa-Lobos, a Brazilian composer, had already done something quite close with his 'Milimeterization'