Abstract:
This dataset contains water column data collected aboard the R/V Sikuliaq in the northern Chukchi Sea from 2017-08-11 to 2017-08-20. Five lines, a total of 23 sites were sampled - 1) the Distributed Biological Observatory 4 (DBO4; n = 9), 2) Hanna Shoal (HS; n = 2), 3) Barrow Canyon (BC; n = 5), 4) Wainwright (WT; n = 5), and 5) Barrow/Hanna Shoal (BHS; n = 2) in water depths ranging from 7 to 117 m, with the deepest sampling stations located in Barrow Canyon. The water sample was collected from Niskin bottles mounted to a CTD rosette system outfitted with SBE 4 Conductivity (n = 2), SBE 3 Temperature (n = 2), SBE 9 plus pressure sensor (n = 1), and SBE 43 and ARO‐CAV dissolved oxygen sensors that were calibrated before departing the port. The dataset includes sample collection information (collection type, location, date, time, latitude, longitude) depth from surface in water, water column salinity, the concentrations of dissolved nutrients, methane concentrations, the methane oxidation rate and turnover rate constant. The in situ concentrations of nitrate, nitrite, and phosphate samples were determined in duplicate on a Lachat QuikChem 8500 autoanalyzer and Beckman 6500 liquid scintillation counter was used to measure methane oxidation rates through radioactive tracer method. This dataset supports the publication: Rogener, M. K., Sipler, R. E., Hunter, K. S., Bronk, D. A., & Joye, S. B. (2019). Pelagic methane oxidation in the northern Chukchi Sea. Limnology and Oceanography. doi:10.1002/lno.11254
Suggested Citation:
Mary-Kate Rogener. 2019. Methane concentration and oxidation rates in water column data collected aboard the R/V Sikuliaq in the northern Chukchi Sea from 2017-08-11 to 2017-08-20. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/n7-38jp-7p37
Purpose:
Determine the role of methanotrophs and methane cycling in an environment undergoing significant environmental shifts due to increasing temperatures and melting sea ice.
Data Parameters and Units:
Location name/ID; Collection type (CTD); Lat (Latitude, decimal degrees); Long (Longitude, decimal degrees); Date (dd/mm/yyyy); Time (Local, L); Time (UTC); Depth (Depth from surface in water, m); Salinity (psu); Ammonium (NH4, uM); Nitrite (NO2, uM); Nitrate + nitrite (NOx, uM); Nitrate (NO3, uM); Dissolved Inorganic Nitrogen (DIN, uM); Total Dissolved Nitrogen (TDN, uM); Dissolved Organic Nitrogen (DON, uM); Dissolved Phosphate (PO4, uM); Total Dissolved Phosphorus (TDP, uM); Dissolved Organic Phosphorus (DOP, uM); Dissolved Inorganic Nitrogen to Phosphorus ratio (DIN:DIP, molar ratio); Dissolved Organic Nitrogen to Phosphorus ratio (DON:DOP, molar ratio); Dissolved Organic Carbon (DOC, uM); Dissolved Methane (CH4, nM); Methanol oxidation rate (pmol L-1 d-1); Methane Oxidation Standard Deviation (pmol L-1 d-1); Methane Turnover Rate Constant (d-1); Methane Turnover Rate Constant Standard Deviation (d-1).
Location: DB04 (the Distributed Biological Observatory 4, n=9); HS (Hanna Shoal, n = 2); BC (Barrow Canyon, n = 5); WT (Wainwright, n = 5); Barrow/Hanna Shoal (BHS, n = 2).
Note: BDL = Below detection Limit.
Methods:
Five lines, a total of 23 sites were sampled - 1) the Distributed Biological Observatory 4 (DBO4; n = 9), 2) Hanna Shoal (HS; n = 2), 3) Barrow Canyon (BC; n = 5), 4) Wainwright (WT; n = 5), and 5) Barrow/Hanna Shoal (BHS; n = 2) in water depths ranging from 7 to 117 m, with the deepest sampling stations located in Barrow Canyon. The water sample was collected from Niskin bottles mounted to a CTD rosette system outfitted with SBE 4 Conductivity (n = 2), SBE 3 Temperature (n = 2), SBE 9 plus pressure sensor (n = 1), and SBE 43 and ARO‐CAV dissolved oxygen sensors that were calibrated before departing the port. Methane samples were collected directly from the Niskin bottle by filling 160‐mL serum nitrogen‐purged vials and were stored at in situ temperature (0 ± 1°C) until shipment back to the University of Georgia, where analyses were performed. Then to ensure minimal atmospheric contamination, from the same Niskin bottle, a 500‐mL Polyethylene Terephthalate Glycol (PETG) bottle was filled using silicon tubing that was inserted to the bottom of the PETG. Hence, the methane oxidation rate assessments were carried out at the University of Georgia shortly after the cruise expedition was concluded. Experimental incubations were conducted at in situ temperature. Samples were incubated for 70 hours. The in situ concentrations of nitrate, nitrite, and phosphate samples were determined in duplicate on a Lachat QuikChem 8500 autoanalyzer as described by Parsons et al., (1984) and Beckman 6500 liquid scintillation counter was used to measure methane oxidation rates through radioactive tracer method as described by Rogener et al., (2018). For more details on methods and anlyses please refer to the associated publication Rogener et al., (2019).
Instruments:
The CTD used to make measurements was a Sea-Bird Scientific SBE 4 Conductivity (n=2), SBE 3 Temperature (n=2), and SBE 9 plus pressure sensor (n=1). Beckman 6500 liquid scintillation counter was used to make measure methane oxidation rates through radioactive tracer method. The in situ concentrations of nitrate, nitrite, and phosphate samples were determined in duplicate on a Lachat QuikChem 8500 autoanalyzer.
Provenance and Historical References:
Parsons, T. R., Y. Maita, and C. M. Lalli. (1984). A manual of chemical and biological methods for seawater analysis. Pergamon Press, Oxford.
Rogener, M. K., Bracco, A., Hunter, K. S., Saxton, M. A., & Joye, S. B. (2018). Long-term impact of the Deepwater Horizon oil well blowout on methane oxidation dynamics in the northern Gulf of Mexico. Elem Sci Anth, 6(1), 73. doi:10.1525/elementa.332