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).