The Aqua satellite platform carries a MODIS sensor that observes sunlight reflected from within the ocean surface layer at multiple wavelengths. These multi-spectral measurements are used to infer the concentration of chlorophyll-a (Chl-a), most typically due to phytoplankton, present in the water. An empirical relationship is then used to compute an estimate of the relative abundance of three phytoplankton size classes (micro, nano and picoplankton).
The methods used to decompose chl_oc3 are described by Brewin et al in two papers in 2010 and 2012. The two methods, denoted Brewin2010at and Brewin2012in, used calibration data from the Atlantic and Indian Oceans respectively. Users should note that these are unvalidated experimental products and they should familiarise themselves with the underlying algorithms and methodologies described in the published literature before making use of them.
The data are produced from the same data stream as the MODIS Chla_oci data set (https://catalogue-imos.aodn.org.au:443/geonetwork/srv/api/records/d7a14921-8f3f-4522-9a54-e7d1df969c8a).
Data are provided as two files per day, one with the percentage of nanoplankton, and one for picoplankton. The percentage of microplankton is computed as the balance to 100%, that is %micro = 100 - %nano - %pico.
This collection was removed from the AODN Portal in March 2023, please refer to the Brewin 2012 collection which supersedes this one - https://catalogue-imos.aodn.org.au:443/geonetwork/srv/api/records/bc428d0b-eff7-41b9-8d4c-10e666ee1312