OOI Coastal Pioneer NES Array Sampling Guidelines

The location of the Coastal Pioneer Array from 2013 through 2022 is the New England Shelf (NES). The Pioneer-NES Array consists of 3 Coastal Surface Moorings, 5-7 Coastal Profiler Moorings (depending on the season), and mobile assets. Coastal Gliders are present in the Array year-round. Coastal Profiling Gliders are present in the Summer at the Inshore and Central sites (they are replaced by Profiler Moorings in the Winter). AUVs are operated in the Array during OOI cruises.

Subsections below define the strategy for sampling in the vicinity of each type of platform.

There are a few general guidelines which also inform the strategies defined below:

Collect 4-6 water samples spaced throughout the water column (7 m, bottom, and 2-3 in between).
Depths selected based on water column stratification and/or location of min/max features (e.g., O2 minimum, Chlorophyll maximum).
Collect Chlorophyll in surface waters down to ~50 m + one deep sample (or where a fluorescence signal is no longer detected).
Collect DIC/TA, pH at 7 m and at the bottom, and DIC/TA at intermediate depths.

Coastal Surface Mooring Sampling

Collect 4-6 water samples spaced throughout the water column (7 m, bottom, and 2-3 in between).
Depths selected based on water column stratification and/or location of min/max features (e.g., O2 minimum, Chlorophyll maximum).
Collect Chlorophyll in surface waters down to ~50 m + one deep sample (or where a fluorescence signal is no longer detected).
Collect DIC/TA, pH at 7 m and at the bottom, and DIC/TA at intermediate depths.

Coastal Profiler Mooring Sampling

Collect 4-6 water samples spaced throughout the water column (7 m, bottom, and 2-3 in between).
Depths selected based on water column stratification and/or location of min/max features (e.g., O2 minimum, Chlorophyll maximum).
Collect Chlorophyll in surface waters down to ~50 m + one deep sample (no need to sample where a fluorescence signal is no longer detected).
Collect Nutrient and Carbon samples even though not measured on mooring; provides a valuable, consistent dataset across the array.
For carbon measurements – pH is most important at depth and at the surface; DIC/TA is important throughout water column and at depths with nutrient sampling.
If reduction in sampling is needed, consider not sampling Nutrients and Carbon at the upstream sites (UI, UO).

Sampling Associated with Mobile Assets

Collect 4-5 water samples spaced throughout the water column (surface, bottom, and 2-3 in between)
Depths selected based on water column stratification and/or location of min/max features (e.g., O2 minimum, Chlorophyll max)
Collect Chlorophyll in surface waters down to ~50 m + one deep sample (no need to sample where a fluorescence signal is no longer detected)
AUVs and Profiling Gliders – sample at 7 m instead of surface, and include nutrient sampling (because these vehicles transit close to Surface Moorings with an NSIF at 7 m).

Methods

Salinity

Salinity measurements are performed following the methodology outlined in the WHOI Hydrography Blue Book, Automated Oxygen Titration and Salinity Determination (Knapp et al. 1990). Measurements are performed using a Guildline Autosal model 8400B salinometer (Guildline Instruments of Canada). Manufacturer stated accuracy and precision at 35 psu is +/- 0.003 psu and 0.0002 psu. IAPSO standard seawater is used to standardize the Autosal daily before runs.

Oxygen

Dissolved oxygen measurements are performed following the methodology outlined in the WHOI Hydrography Blue Book Automated Oxygen Titration and Salinity Determination (Knapp et al. 1990). Measurements are performed using a Metrohm Model 888 Titrando dosing device, with the titration endpoint determined amperometrically. Stated accuracy is 0.02 ml/l, with a precision of 0.001 ml/l.

Nutrients

All nutrient values are reported as the average of triplicate analysis on a single collected sample.

Carbon System

Carbon system measurements are performed by the Wang lab (Woods Hole Oceanographic Institution). DIC and TA measurements follow the methodology of Wang and Cai (2004) with uncertainties of 2 umol/kg. DIC measurements are performed with an Apollo Sci-Tech AS-C3. TA measurements are performed with an Apollo Sci-Tech AS-ALK2 and ROSS electrode. pH measurements follow the methodology of Clayton and Byrne (1993) with an uncertainty of 0.002 pH units using an Agilent 8453.

Chlorophyll and Phaeo

Analysis was completed using a Turner Designs Aquafluor Handheld 800446