Phytoplankton
EO Capability Benefits
Monitoring phytoplankton through Earth Observation (EO) technologies, such as satellite remote sensing, allows for continuous and large-scale assessment of their distribution, density, and productivity. It is particularly valuable for detecting harmful algal blooms (HABs), which can disrupt ecosystems and pose health risks to humans and marine life. Furthermore, tracking phytoplankton trends over time helps identify environmental stressors such as nutrient pollution, ocean warming, and acidification. EO-based monitoring of phytoplankton can provide early warning signals for ecosystem disturbances, support sustainable fisheries management, and inform adaptive responses to climate variability, ultimately contributing to food security and marine conservation.
EO Capability Description
Phytoplanktons are microscopic, photosynthetic organisms that serve as the primary producers in marine ecosystems, forming the base of the oceanic food chain. They not only fuel marine food webs, but also contribute significantly to carbon sequestration, mitigating the effects of climate change. They play a pivotal role in global biogeochemical cycles, particularly in carbon cycling, by absorbing large amounts of atmospheric carbon dioxide during photosynthesis and converting it into organic matter; this process is known as Net Primary Production (NPP).
Phytoplankton biomass can be assessed using a combination of satellite-based Earth Observation (EO) data and numerical models to estimate phytoplankton concentrations and NPP. Sentinel-3 Ocean Colour data analysis helps determine chlorophyll-a concentrations, which serve as a reliable indicator of phytoplankton abundance. This data provides a clear picture of the distribution and density of phytoplankton across large areas of the marine environment.
To complement the satellite observations, numerical models – from the Copernicus Marine Environment Monitoring Service (CMEMS), for example – enable the simulation of phytoplankton growth and NPP. These models factore in key environmental conditions, including sea surface temperature, light availability, and nutrient levels, all of which influence phytoplankton dynamics. Validation against in-situ measurements and historical datasets ensures the accuracy and consistency of the results.
The typical depth range where phytoplankton thrive in meaningful concentrations is throughout the upper 50 meters of the water column. Temporal trend analysis using monthly and annual average maps at a 50-meter depth enables the estimation of total biomass carbon, which is then converted into tons to assess the potential blue carbon sequestered by phytoplankton.
Key outputs include detailed maps of phytoplankton concentration, net primary production, and the corresponding total biomass carbon. These results provide essential insights into the role of phytoplankton in carbon cycling and support efforts to manage marine ecosystems sustainably.
