Dataset: Discrete Net Community and Gross Primary Production Rates data on the US Northeastern Shelf in the SPIROPA project during spring and summer 2018 and 2019

Discrete samples of triple oxygen isotopes (TOI) were collected from the surface Niskin bottles on the CTD-rosette system at all stations as well as on some cruises from the underway system between stations. Samples were collected in custom-made ~500-mL sample bottles which were pre-poisoned with 100 µl of saturated mercuric chloride solution and filled with around 300 mL of seawater from the underway system or from the Niskin at each station (Stanley et al., 2015). Samples were brought to Woods Hole Oceanographic Institution where they were analyzed for TOI with a custom-made processing line and a Thermofisher MAT 253 isotope ratio mass spectrometer as detailed in Stanley et al (2015), that was based on the method of Barkan and Luz (2003). The same samples were also analyzed for O2/Ar which yielded rates of NCP from discrete data as well as an independent method for calibrating the EIMS (see associated dataset). Corrections for the effect of argon on the triple oxygen isotope ratio and the effect of varying sizes of the sample vs. reference standard were made for every sample. Typical lab Reproducibilities from duplicate samples collected on these cruises ranged from 4 to 8 per meg for 17Δ, 0.008 to 0.03 per mil for δ17O, and 0.008 to 0.05 per mil for δ18O depending on the cruise. Confirmation that the water from the underway system was representative of the oceanic TOI signature of dissolved oxygen was obtained by comparing samples collected from the underway system to those collected concurrently from the surface Niskin bottle.