The CoastObs primary productivity product represents the amount of carbon (or organic material) fixed per area over time by phytoplankton in coastal waters, which is of particular interest to end-users such as environmental managers and aquaculture producers.

What is the problem

Approximately 50% of global net primary production (PP) is attributed to ocean phytoplankton. Phytoplankton PP removes carbon from the surface ocean, playing a major role in regional and global carbon cycling, food web dynamics, biogeochemical cycles and marine fisheries. Earth observation (EO) provides a useful tool for monitoring PP in coastal waters, however most existing satellite derived models have been developed and validated using data from open oceans.

CoastObs solutions

The launch of the Sentinel satellites has opened up new opportunities for monitoring of coastal ecosystems. EO provides the opportunity to monitor the frequent changes in phytoplankton abundance in coastal waters, using the photosynthetic pigment chlorophyll-a (Chl-a) as a proxy. The CoastObs PP model is a depth-integrated model that derives PP as a function of daily phytoplankton carbon fixation within the euphotic zone per unit of water surface area (mg C/m2/day). The model is parameterised using satellite-derived Chl-a, euphotic depth, sea surface temperature and daily photosynthetically available radiation (PAR).