Qiu, Li; Browning, Thomas J; Voß, Daniela; Achterberg, Eric Pieter (2025): Carbonate chemistry and other variables observed during RV METEOR cruise M187 (ReSEAt) from Walvis Bay, Namibia to Walvis Bay, Namibia [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.984417
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Published: 2025-08-20 • DOI registered: 2025-09-18
Abstract:
Carbonate chemistry parameters (pH, total alkalinity [TA], and partial pressure of CO₂ [pCO₂]) along with other oceanographic variables (temperature, salinity, nitrate [NO₃⁻], chlorophyll a [Chl a], and dissolved oxygen [DO]) were measured during the RV METEOR cruise M187 (ReSEAt; 25 January – 2 March 2023; Walvis Bay, Namibia – Walvis Bay, Namibia) using a suite of sensors . Surface water measurements of TA, pCO₂ and pH were obtained using an in situ total alkalinity analyzer (ISA-TA) with a ~7-minute sampling interval, a pCO₂ sensor (HydroC, 4H-Jena Engineering GmbH, Germany) with a 1-minute interval and a pH sensor (Sunburst Sensors, USA) with a 15-minute interval, respectively. All sensors (ISA-TA, pCO₂, pH, and nitrate) were installed in a 68 L tank positioned on a laboratory sink, which was continuously supplied with underway surface seawater (from a depth of ~5 m) during filament tracking. The water flow rate into the tank was maintained at approximately 30 L/min, enabling rapid turnover and ensuring near-real-time measurement of changing water properties. Sensor deployment and data acquisition followed established protocols as described in Qiu et al. (2023a, 2023b, 2024), Fietzek P., et al. (2014) and Nehir M., et al. (2021). We defined the relative coordinates of each cross-filament section (1 to 12), with –1 and +1 representing the southern and northern boundaries (distance normalized), respectively. These boundaries were determined based on the maximum density gradient on each side. Subsequently, all data were interpolated onto a uniform grid ranging from -6 to 6 with a spacing interval of 0.01. Chl a and dissolved oxygen values were provided by a PocketFerryBox system.
Related to:
Fietzek, Peer; Fiedler, Björn; Steinhoff, Tobias; Körtzinger, Arne (2014): In situ Quality Assessment of a Novel Underwater pCO2 Sensor Based on Membrane Equilibration and NDIR Spectrometry. Journal of Atmospheric and Oceanic Technology, 31(1), 181-196, https://doi.org/10.1175/JTECH-D-13-00083.1
Nehir, Münevver; Esposito, Mario; Begler, Christian; Frank, Carsten; Zielinski, Oliver; Achterberg, Eric Pieter (2021): Improved Calibration and Data Processing Procedures of OPUS Optical Sensor for High-Resolution in situ Monitoring of Nitrate in Seawater. Frontiers in Marine Science, 8, 663800, https://doi.org/10.3389/fmars.2021.663800
Qiu, Li; Esposito, Mario; Martínez-Cabanas, María; Achterberg, Eric Pieter; Li, Quanlong (2023): Autonomous high-frequency time-series observations of total alkalinity in dynamic estuarine waters. Marine Chemistry, 257, 104332, https://doi.org/10.1016/j.marchem.2023.104332
Qiu, Li; Jiang, Kunshan; Li, Quanlong; Yuan, Dongxing; Chen, J; Yang, Bo; Achterberg, Eric Pieter (2024): Variability of total alkalinity in coastal surface waters determined using an in-situ analyzer in conjunction with the application of a neural network-based prediction model. Science of the Total Environment, 908, 168271, https://doi.org/10.1016/j.scitotenv.2023.168271
Qiu, Li; Li, Quanlong; Yuan, Dongxing; Chen, J; Xie, Jiezhen; Jiang, Kunshan; Guo, Liguo; Zhong, Guibin; Yang, Bo; Achterberg, Eric Pieter (2023): High-Precision In Situ Total Alkalinity Analyzer Capable of Month-Long Observations in Seawaters. ACS Sensors, 8(7), 2702-2712, https://doi.org/10.1021/acssensors.3c00552
Funding:
Coverage:
Median Latitude: -24.748648 * Median Longitude: 12.249839 * South-bound Latitude: -25.385940 * West-bound Longitude: 11.856180 * North-bound Latitude: -24.292170 * East-bound Longitude: 13.048880
Date/Time Start: 2023-01-26T17:29:34 * Date/Time End: 2023-02-02T03:23:46
Event(s):
M187_0_Underway-4 * Latitude Start: -22.949682 * Longitude Start: 14.497892 * Latitude End: -25.231970 * Longitude End: 2.681547 * Date/Time Start: 2023-01-25T08:00:00 * Date/Time End: 2023-03-01T07:58:00 * O2A Registry URI: https://hdl.handle.net/10013/registry.4fb1084b-2825-40b4-904d-f519cb9a2d94 * Campaign: M187 (ReSEAt) * Basis: Meteor (1986) * Method/Device: PocketFerryBox, 4H Jena Engineering, [SN: 751502] * Comment: event was not logged in DSHIP
Parameter(s):
| # | Name | Short Name | Unit | Principal Investigator | Method/Device | Comment |
|---|---|---|---|---|---|---|
| 1 | DATE/TIME | Date/Time | Qiu, Li | Geocode | ||
| 2 | LONGITUDE | Longitude | Qiu, Li | Geocode | ||
| 3 | LATITUDE | Latitude | Qiu, Li | Geocode | ||
| 4 | Identification | ID | Qiu, Li | Underway data were divided into 13 sections along a direction perpendicular to the filament extension | ||
| 5 | Distance | Distance | m | Qiu, Li | Normalized distance | |
| 6 | Temperature, water | Temp | °C | Qiu, Li | Digital oceanographic thermometer, Sea-Bird, SBE 38 | |
| 7 | Salinity | Sal | Qiu, Li | Thermosalinograph Seacat SBE-21 system with SBE 38 | ||
| 8 | Alkalinity, total | AT | µmol/kg | Qiu, Li | ISA-TA analyzer | |
| 9 | pH | pH | Qiu, Li | Inexpensive ocean pH sensor for surface applications, iSAMI-pH, Sunburst Sensors (iSAMI-pH) | ||
| 10 | Carbon dioxide, partial pressure | pCO2 | µatm | Qiu, Li | HydroC pCO2 sensor, CONTROS | |
| 11 | Wind speed | ff | m/s | Qiu, Li | Ultrasonic Anemometer 2D, Thies Clima | |
| 12 | Nitrate | [NO3]- | µmol/kg | Qiu, Li | TriOS nitrate sensor | |
| 13 | Oxygen | O2 | µmol/kg | Qiu, Li | PocketFerryBox, 4H Jena Engineering, [SN: 751801] | Aanderaa 4835 |
| 14 | Chlorophyll a | Chl a | µg/l | Qiu, Li | PocketFerryBox, 4H Jena Engineering, [SN: 751801] | Seapoint SCF 3962 |
License:
Creative Commons Attribution 4.0 International (CC-BY-4.0) (License comes into effect after moratorium ends)
Status:
Curation Level: Enhanced curation (CurationLevelC)
Size:
96295 data points
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