The ocean plays a vital role in sustaining life on planet Earth, both providing us with living resources and regulating our climate. The trajectory of current and future anthropogenically driven climate change will be very substantially controlled by the ability of the ocean to continue absorbing the 93% of excess heat and 30% of anthropogenic carbon entering the atmosphere that it currently takes up. The Atlantic Ocean is particularly important as the Atlantic Meridional Overturning Circulation (AMOC) transports heat northwards, keeping north-west Europe 3 degrees warmer than comparable latitudes in N America and Asia. The heat loss associated with the AMOC facilitates intense solubility-driven uptake of both natural and anthropogenic carbon. The Atlantic also supports spatially and temporally diverse biological communities in the water column and at the seafloor which constitute biodiversity reservoirs, act to store carbon in the oceans, and underpin the marine food web; in essence the ocean's natural capital. We now have abundant evidence that many features of the Atlantic Ocean and its marginal seas are changing, including the strength of the thermohaline and wind-driven circulation, sea surface and interior temperature and salinity distributions, air-sea CO2 fluxes, primary production and nutrient fields. These changes may constitute significant threats, by driving fundamental, but poorly understood, changes in the benefits we derive from the Atlantic Ocean.
In an era of rapid planetary change, expanding global population and intense resource exploitation, it is vital that we have internationally coordinated observing and prediction systems so policy makers can make sound evidence-based decisions about the ocean. CLASS will take the powerful synergistic approach of using a range of internationally coordinated observations and world-class numerical models to assess the current status and future evolution of the role Atlantic Ocean systems play in regulating key aspects of ocean services. It will support the UK element of international ocean observing and modelling programmes, prioritising the use of autonomous vehicles and new sensors to improve efficiency, and increase the spatial and temporal coverage of our ocean observations, while reducing dependence on expensive research ships. These underpinning activities will provide a platform for future funding investments for the academic community and contribute key datasets and model outputs that can be used across the UK and global community to address important marine policy relevant questions. Finally, we will create effective engagement activities ensuring academic partners have transparent access to NERC marine science capability through graduate training partnerships and access to shipborne, lab-based and autonomous facilities, and modelling capabilities.