An integrative approach to unravel the ocean's biological carbon pump

ongoing

The ocean’s biological carbon pump plays a crucial role in storing atmospheric carbon dioxide in the deep ocean, thereby isolating carbon from the atmosphere for decades to centuries. Yet, its capacity to do so is under-constrained and its mechanisms poorly understood. CarbOcean will develop a mechanistic and quantitative understanding of the biological carbon pump using a novel integrative approach that accounts for its two component pumps: (1) the organic carbon pump, which concerns the photosynthetic production of particulate organic carbon, POC, and (2) the carbonate pump, which concerns the production of particulate inorganic carbon, PIC. These pumps have opposite effects on the ocean-atmosphere exchange of carbon dioxide. I will nurture the development of a breakthrough autonomous robotic ocean profiler, uniquely capable of simultaneous observations of PIC and POC fluxes and physicochemical parameters from the well-lit surface ocean through the underlying twilight zone (roughly 100 – 1000 m depth) over a continuum of spatiotemporal scales. The robotic profilers will be deployed in a wide variety of oceanic environments and the collected data will allow investigation of links between the export and sequestration of POC and PIC, examination of pump interconnection, and detection of pump drivers. New parameterizations of carbon flux processes will be developed and implemented in a biogeochemical model. Lastly, the carbon flux data collected will be up-scaled to the global ocean using artificial intelligence approaches, thereby exploiting synergies among various observational platforms, including remote sensing. CarbOcean is a strongly interdisciplinary project, connecting fundamental and applied optical oceanography with biogeochemistry, carbonate chemistry, advanced statistics, and technological development that will allow a quantum leap in understanding the ocean’s biological carbon pump.