High-Resolution Data Collection for Constraining Carbon Storage Rates and Acidification in the Arctic Ocean

The Arctic Ocean is one of the least understood regions of the global ocean when it comes to how seawater chemistry is changing over time. This project will collect new measurements during the ARC01 GO-SHIP expedition crossing the Arctic from Norway to Alaska, gathering chemical signals of carbon dissolved in seawater that reveal how the ocean takes up and stores carbon dioxide. These measurements fill a critical gap and will be compared to older, sparser data sets in the region to evaluate changes over time. The effort is an important component of global carbon cycling and our understanding of carbon biogeochemistry. The broader impacts include training graduate and undergraduate students, strengthening international science collaborations, and expanding public outreach. This project will measure the stable isotope composition of dissolved inorganic carbon (δ13C-DIC) during the GO-SHIP ARC01 expedition traversing both the Eurasian and Amerasian basins. Combined with co-located hydrographic, biogeochemical, inert tracers, and other inorganic carbon parameters, and integrated with prior datasets, these measurements will be used to estimate recent rates of carbon accumulation across distinct Arctic water masses and to characterize the source of excess DIC driving subsurface acidification. Because δ13C-DIC carries a much longer air-sea equilibration timescale than DIC alone, it provides an independent tracer of carbon sources and export pathways, substantially expanding spatial and temporal coverage in this data-sparse region. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria. NSF Award ID: 2520962 | Program: 0100CYXXDB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: Wei-Jun Cai | Institution: University of Delaware, NEWARK, DE | Award Amount: $595,001 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2520962 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2520962.html