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Ocean Color Image Gallery

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World Map of Chlorophyll-a

The Ocean Biology Processing Group produces level-3 satellite data which comprise level-2 derived geophysical variables that have been spatially aggregated/projected onto a well-defined spatial grid over a well-defined time period. Unwanted values are excluded. We archive two types of level-3 data.

The above level-3 image was generated from the Remote Sensing Reflectances (Rrs) in the red, green, and blue spectrum of Aqua MODIS corresponding to bands 667, 555, and 410 nanometers. As a level-3 image, it is made from the composited level-2 Rrs files that fall into the Rolling 32 Day time period. Shades of green are used to highlight the presence of chlorophyll-a. In the marine environment, chlorophyll-a is a proxy for phytoplankton biomass. High intensity greens indicate greater concentrations of phytoplankton, which denotes very productive regions of the oceans. Blue areas indicate limited amounts of phytoplankton in "oligotrophic" waters where enough nutrients aren't produced to sustain algae blooms.

File used:
A20212732021304.L3m_R32_RRS_Rrs_412_4km.nc
A20212732021304.L3m_R32_RRS_Rrs_555_4km.nc
A20212732021304.L3m_R32_RRS_Rrs_667_4km.nc