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The Ocean Observatories Initiative (OOI) deployed both the In-Situ Ultraviolet Spectrophotometer (ISUS) and Submersible Underwater Nitrate Sensor (SUNA) for continuous, in-situ measurement of nitrate. At the Pioneer-New England Shelf Array (Pioneer-NES), ISUS/SUNA sensors were deployed at 7-meters depth at the Inshore (ISSM), Central (CNSM), and Offshore (OSSM) Surface Mooring locations. The SUNA sensor replaced the ISUS sensors spring 2018. The SUNA was a major improvement in technology, with significant improvements in accuracy and precision. However, it still suffers from calibration drift due to lamp fatigue and biofouling as well as spectral interference due to bromide and fluorometric CDOM. Drift is corrected by application of post-cruise calibrations to recalculate the temperature-and-salinity corrected nitrate concentration following Sakamoto (2009a) and estimating a linear drift between pre-and-post cruise deployments. Validation is performed by comparison with discrete water samples collected during deployment/recovery of the sensors. These datasets include the nitrate data from the Pioneer-NES ISSM (CP03ISSM-RID26-07-NUTNRB000.nc), CNSM (CP01CNSM-RID26-07-NUTNRB000.nc), and OSSM (CP04OSSM-RID26-07-NUTNRB000.nc) SUNA instruments spanning Spring 2018 through Fall 2022. Each dataset contains the measured nitrate, the temperature-salinity corrected nitrate, the drift-corrected nitrate, and the nitrate following validation with bottle samples.
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Lab-on-chip nitrate + nitrite and silicate sensors on Ocean Observing Initiative (OOI) Southern Ocean Surface Mooring from December 2018 to January 2020.
Two Lab-on-Chip sensors, one measuring nitrate + nitrite (here after nitrate) and one measuring silicic acid (here after silicate), were deployed on the Ocean Observing Initiative (OOI) Southern Ocean Array surface mooring at a depth of approximately 12m on the near surface instrument frame in the southeast Pacific Ocean (-54 N, -89W). The nitrate sensor operated as expected for the full deployment period (6/12/2018 to 19/1/2020), collecting daily measurements. The silicate sensor operated as expected for almost ten months (until 1/10/2019), collecting up to four measurements per day. The OOI surface mooring was deployed in December 2018 on research cruise DY096 and recovered in January 2020 on research cruise DY112. The sensors and associated research cruises (DY096 and DY112) were supported by the Natural Environment Research Council (NERC) RoSES Carbon Uptake and Seasonal Trends in Antarctic Remineralisation Depth (CUSTARD) project. This material is based upon work supported by the Ocean Observatories Initiative, which is a major facility fully funded by the National Science Foundation (NSF).
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- Award ID(s):
- 2244833
- PAR ID:
- 10627712
- Publisher / Repository:
- NERC EDS British Oceanographic Data Centre NOC
- Date Published:
- Subject(s) / Keyword(s):
- oceans
- Format(s):
- Medium: X Other: Binary; Delimited
- Location:
- (East Bound Longitude:-37.266667 ; North Bound Latitude:3.50171899829913 ; South Bound Latitude:-60 ; West Bound Longitude:131.023611 )
- Sponsoring Org:
- National Science Foundation
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