Guide to the Creation and Use of Ocean-Colour, Level-3, Binned Data Products.

Abstract

One of the goals of launching a number of ocean-colour sensors aboard various satellites is to build a long-term, multi-sensor, multi-year, ocean-colour archive. The derived chlorophyll concentrations (in time and space) can be used to resolve inter-annual-to-decadal changes in oceanic phytoplankton biomass in response to global environmental changes. This report examines issues related to the diversity in current “binning” schemes used for ocean-colour data, and recommends basic approaches that could be used across agencies or projects, in parallel to the current schemes. Issues related to merging of ocean-colour data from different sensors are also addressed, as well as the synergistic use of ocean colour with other satellite-derived observations, such as sea-surface temperature. The aim of the report is not to define the best way to generate Level-3 ocean colour data products from Level-2 data, which is outside the scope of this study, but rather to list previously unconsidered issues that may impair the use, intercomparison or merging of Level-3 ocean-colour data sets, as well as their application with other satellite-derived data sets.