Carbon from earth Observation between Ocean and Land — COOL

While the coastal ocean plays a critical role in the ocean carbon cycle, its observation from remote sensing satellites is limited by the optical complexity of coastal waters and other effects, such as sea surface glint and land adjacency, that affect the satellite signal and its atmospheric correction. Therefore, satellite-retrieval algorithms developed to study the ocean carbon cycle are not easily transferable to the coastal regions. Also, the spatial and temporal resolution achieved for global ocean carbon products would not be adequate to fully understanding the dynamic, fine-scale processes that occur in coastal regions.

The Carbon from earth Observation between Ocean and Land (COOL) project aims to address these limitations and focus on further developing and implementing satellite retrieval algorithms for different carbon pools and fluxes at high spatial and temporal resolution to improve our understanding of highly dynamic coastal processes. It focuses on those carbon pools and fluxes for which algorithms are relatively mature, and for which we can have some certainty in their application in the coastal ocean at the global scale in the near future. These include Particulate Organic Carbon, Particulate Inorganic Carbon, Dissolved Organic Carbon and Primary Production. Related, non-carbon, products include remote sensing reflectances, chlorophyll-a, suspended particulate matter and coloured dissolved organic matter.

In particular, COOL will:

• review the scientific questions, in situ datasets, satellite retrieval algorithms and risks associated with coastal carbon products in the selected study regions.
• apply and adapt existing algorithms (e.g., SCOPE, CoastalCarbonMapper) to higher resolution Sentinel 3 OLCI data and develop new ones when needed, comparing results with coarser products.
• generate a ten year coastal carbon dataset, validate it with independent in situ data such as HyperBOOST, and quantify uncertainties.
• use the COOL dataset in two science cases to demonstrate the value of higher resolution products across contrasting water types, dynamic processes and biogeochemical conditions.
• produce a five year roadmap for advancing coastal carbon EO by integrating project insights and guidance from the scientific community.
• collaborate with the wider community, including EU projects like LAndSeaLot, to develop synergies and expand the use of the COOL dataset.
• disseminate COOL results through peer reviewed publications, scientific conferences and a dedicated project website supported by communications experts.