Here we offer the level-3 MODIS chlorophyll-a concentration and other parameters derived from MODIS collection 6 radiances applying the v2014.0 reprocessing.
Solar radiance penetrates into the water. Its absorption depends, among other factors, on the amount of chlorophyll-a stored in the cells of the plankton. By measuring the water-leaving radiance at two different wavelengths of which one is at the absorption band of chlorophyll-a one can estimate the chlorophyll-a concentration.
Data offered here are based on the Ocean Color Chlorophyll (OC3) v6 algorithm. It combines calibrated radiances measured by MODIS at two different wavelengths of which one is in the blue and the another is in the green part of the electromagnetic spectrum. Chlorophyll-a concentration is derived using a fourth order polynomial based on the ratio of the blue to the green channel radiances in logarithmic scale. The algorithm is suited for so-called Case 1 waters (low concentrations of sediments and yellow substances).
More information is given in the references as well as on https://oceancolor.gsfc.nasa.gov/cms/atbd.
We also recommend to take a look on the production & processing release website: https://oceancolor.gsfc.nasa.gov/cms/reprocessing
We offer data of both satellites_ EOS-TERRA and EOS-AQUA. Data with daily resolution are processed but we can provide these data only upon request thanks to the large data volume.
Last update of the data set at ICDC: October 20, 2017.