The latest version of the OC-CCI dataset is 4.1 that comprises of globally merged MERIS, Aqua-MODIS, SeaWiFS and VIIRS data with associated per-pixel uncertainty information. This is an update of the version 4.0 product that had erroneous data within the Chlorophyll product:
The OC-CCI team noticed that the algorithm blending designed to optimise the chlorophyll-a product across a range of optical environments was corrupted in the operational code, with the consequence that the chlorophyll-a product released as part of OC-CCI v4.0 (released in June 2019) is based uniquely on the OC3 algorithm, rather than on blended algorithms. The chlorophyll-a product (and associated uncertainties) are the only products affected. We have now recomputed the chlorophyll-a product using the blending scheme and are releasing an updated v4.1 dataset. If you were using products such as Rrs, water class memberships or IOPs then the products remain unchanged, compared with v4.0.
Further details are available within http://esa-oceancolour-cci.org/sites/esa-oceancolour-cci.org/files/oc-cci_v4_diffs.pdf