This data set contains biogeochemical measurements from an estuary and river adjacent to Cambridge Bay, Nunavut, Canada collected in 2017-2018. Methane and nitrous oxide concentration and water isotopic composition samples were collected from niskin bottles or a submersible pump. Conductivity, temperature, and depth data from a CTD sensor is provided for each sample. The data set also includes high-frequency observations of methane, carbon dioxide, salinity, temperature, and depth made with a novel robotic kayak with biogeochemical sensors (the ChemYak) during ice melt in the estuary in 2018.

Supplement to: Manning, Cara C M; Preston, Victoria L; Jones, Samantha F; Michel, Anna P M; Nicholson, David P; Duke, Patrick J; Ahmed, Mohamed M M; Manganini, Kevin; Else, Brent G T; Tortell, Philippe Daniel (accepted): River inflow dominates methane emissions in an Arctic coastal system. Geophysical Research Letters, e2020GL087669