Autonomous Particulate Inorganic Carbon Sensor and Carbon Explorer Deployment

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

The PI's request funding to complete the development of Particulate Inorganic Carbon (PIC) sensors to create an integrated system for autonomous profiling of a suite of parameters that characterize the ocean's biological pump. The proposed system will measure PIC, Particulate Organic Carbon (POC) and a measure of the Carbon Flux Index (CFI) chlorophyll fluorescence, conductivity and temperature, and likely other parameters. This suite of sensors will characterize the ocean's biological pump, as well as its sensitivity to changing environmental conditions. It is being designed for over-the-side CTD packages as well as autonomous, neutrally buoyant floats and gliders. The ocean's biotic carbon pump exports approximately 10 Pg C/year of particulate organic matter below 100 m. It is fueled by phytoplankton populations, which turn over completely on week time scales. The bio-carbon pump is thus fast and very dynamic, but is poorly observed by conventional means. The changes in its substantial carbon flows brought by effects of CO2 induced global ocean warming and ocean acidification, are not predictable. Better observations of key biological pump variables, including concentration variability of Particulate Inorganic Carbon and Particulate Organic Carbon (PIC and POC) will enable prediction of the evolving carbon cycle of the ocean. Knowledge of the PIC dynamics is fundamental to the understanding and prediction of carbon sedimentation and depth profiles of remineralization. Broader Impacts: The broader impacts of this work are clear in its fostering of a better understanding of the ocean carbon cycle. This is critical to track the role of the oceans in the fate of anthropogenic CO2. To be able to easily and autonomously measure profiles of PIC would provide a wealth of badly needed data for remarkably little cost, shiptime, and effort. It would also compliment the work currently being done to image the particles that exist in the deep sea. The PI instructs a large number of undergraduate and graduate students and will involve them in the results of these tests. The project involves an undergraduate assisting in laboratory testing and at sea field trials.