This data set includes nutrient measurements of water samples collected at hydrographic stations from the Research Vessel (R/V) Sikuliaq during the Arctic Chief Scientist Training cruise June 6–12, 2023 sponsored by the University National Oceanographic Laboratory System (UNOLS) Arctic Icebreaker Coordinating Committee and the National Science Foundation. SKQ202309T was utilized as a training expedition for early-career Arctic oceanographers, focusing on skills essential for leading research cruises. Training topics centered on logistics, how to request time on ships, how to coordinate personnel and equipment, how to plan for operations and survey tasks at sea, how to work with vessel crew and staff, and how to edit research plans based on field conditions. Participants collected various data sets opportunistically throughout the research training. The cruise transited from Seward to Nome and water samples were collected at six hydrographic stations for nutrients (this data set). Specifically, this data set contains nutrient (total dissolved phosphorus (TDP), total dissolved nitrogen (TDN), phosphate, and nitrate+nitrite) measurements at surface and above seabed water depths. Bottle samples were collected in high-density polyethylene (HDPE) bottles which were rinsed at least three times before filling. The bottles were frozen at -40 Celsius (C). 
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                            Sediment geochemical data from the Bering Shelf and Yukon Delta, Eastern Bering Sea, June 2023
                        
                    
    
            This dataset contains geochemical and grain size measurements of seabed and suspended sediment samples collected from the Bering Shelf and Yukon prodelta in June 2023. These samples were collected during the 6-12 June 2023 Arctic Chief Scientist Training Cruise, which was a short cruise on the R/V Sikuliaq during its transit from Seward, Alaska to Nome, Alaska. The cruise was sponsored by the University National Oceanographic Laboratory System (UNOLS) Arctic Icebreaker Coordinating Committee and the National Science Foundation. These data were generated as a pilot data set to understand the fate of terrestrial organic carbon in the Yukon River delta and adjacent Bering Sea. Seabed sediment was collected at three locations (MC04, MC06, and MC08) using a multicorer. One seabed sediment sample was collected using a van veen grab sampler. Suspended sediment samples were collected using a hand-deployed niskin bottle and transferred into a clean 10-liter cubitainer for transport and temporary storage. Suspended sediment was filtered on the ship within 24 hours of collection using a Geotech barrel filter with a 0.45 micron Polyethersulfone (PES) membrane filter. Multicores were extruded on deck and subsamples were transferred to sterile whirl-pak sample bags. All sediment samples were frozen and subsequently shipped back to the lab in coolers. Sediment samples were analyzed for grain size, bulk elemental composition via X-ray fluorescence (XRF), and organic carbon and nitrogen concentrations and isotopes via EA-IRMS (elemental analyzer-isotope ratio mass spectrometry). Grain size distributions were measured using a Malvern mastersizer laser diffraction particle size analyzer at the University of Colorado Boulder. Bulk elemental composition was measured on the Rigaku XRF in the Analytical Geochemistry Lab at the University of New Mexico. Total organic carbon (TOC), total nitrogen (TN), and carbon/nitrogen isotopes were measured at the Center for Stable Isotopes at the University of New Mexico. Prior to EA-IRMS analyses, sediment samples were acid-treated to remove inorganic carbon following the method of Galy et al., 2007. References Galy, V., Bouchez, J., & France‐Lanord, C. (2007). Determination of total organic carbon content and δ13C in carbonate‐rich detrital sediments. Geostandards and Geoanalytical research, 31(3), 199-207. 
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                            - Award ID(s):
- 2303606
- PAR ID:
- 10588559
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- sediment carbon XRF delta multicore suspended sediment
- Format(s):
- Medium: X Other: text/xml
- Sponsoring Org:
- National Science Foundation
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