Dataset: Nitrous oxide concentration, stable isotope and isotopomer data for the GEOTRACES (An International Study of the Marine Biogeochemical Cycles of Trace Elements and Isotopes) Arctic section (summer 2015)

• Main Authors: Bourbonnais, Annie, Altabet, Mark
• Format: Dataset
• Language: English
• Published: NSF Arctic Data Center 2021
• Subjects: nitrous oxide; nitrous oxide stable isotopes; nitrous oxide isotopomers; nitrous oxide concentrations; greenhouse gases; climate change; CHINARE; western Arctic; Chukchi sea; Bering Strait; Arctic; Arctic Ocean; Chukchi Sea; Chukchi; Climate change
• Online Access: https://dx.doi.org/10.18739/a2n58cm9s; https://arcticdata.io/catalog/view/doi:10.18739/A2N58CM9S

Nitrous oxide is a potent greenhouse gas in the troposphere and an ozone-depleting substance in the stratosphere, yet its sources and sinks in the ocean are neither well-quantified nor well understood. Nitrous oxide is both produced and consumed by microbial processes; it is produced by different processes dependent upon the amount of oxygen present locally. High nitrous oxide saturations were recently observed in productive shallow Arctic shelf waters. The primary goal of this dataset is to evaluate nitrous oxide cycling in the Western Arctic Ocean from its concentrations, stable isotopes and isotopomers during the 2015 US Arctic GEOTRACES expedition (cruise ARC01). The project will use isotopic and isotopomer measurements from both shelf and offshore waters to constrain estimates of nitrous oxide cycling in the Arctic. The data will be used to evaluate 1) the pathways of nitrous oxide production from either nitrification following organic matter decomposition in the water column or coupled nitrification-denitrification in the sediments and 2) how these processes influence nitrous oxide exchanges between the surface layer and the atmosphere. Comparisons of observations at coastal and shelf stations in the Bering and Chukchi seas with those offshore in the Deep Canadian Basin will allow the evaluation of the effects of mixing and long-range transport on geochemical signals. The measurements will also serve as a baseline for future assessment of change.