Instrumentation Updates for Planned Pioneer MAB Array

Community Input

The Ocean Observatories Initiative Facilities Board (OOIFB), sponsored by the National Science Foundation (NSF) and in partnership with KnowInnovations, facilitated two community workshops, called Innovations Labs, that resulted in the decision to relocate the Pioneer Array to the southern Mid-Atlantic Bight (MAB). The second Lab included community input on measurements that would be desirable for the relocated array. More than 40 instruments or measurement types were discussed. This was reduced to about a dozen high-priority recommendations based on consensus among the Innovations Lab sub-groups. After considering applicability to the science themes, technical readiness level, operational feasibility, and budget impacts the OOI Program was able to implement the majority of the high-priority recommendations.

Among the goals for the relocation process was to optimize the use of existing inventory, and it was possible to do so while addressing several of the instrumentation recommendations. In some cases, new procurements were required, although it should be noted that one of these procurements was needed to replace an obsolete core sensor. A summary of the instrumentation updates for the proposed Pioneer MAB relocation in these two categories is provided below.

Repurposing of Existing Core Instruments

The OOI deploys a set of core instruments across all the Arrays. Reconfiguration of the Pioneer Array elements, along with some inventory available from the decommissioned southern hemisphere arrays, meant that some instrumentation could be repurposed for the Pioneer MAB Array without requiring new purchases. Five instrumentation changes were made using this approach:

  • Near-surface temperature and salinity: A Seabird SBE-37 CTD will be mounted on the “foot” of the five Coastal Profiler Mooring (CPM) buoys.
  • Incident radiation: A Sea Bird OCR-507 multispectral radiometer will be mounted on the tower of the three Coastal Surface Mooring (CSM) buoys. This instrument will measure downwelling radiation per unit area.
  • Surface wave spectra: A TriAxys Next Wave sensor will be added to the buoy well of all three CSMs. These sensors, which provide both non-directional and directional wave parameters, were previously deployed on only the Central CSM for the Pioneer NES.
  • Turbidity:  Seabird ECO triplet instruments with a secondary turbidity calibration on the optical backscatter channel will be deployed on the Near Surface Instrument Frame (NSIF) and seafloor Multi-Function Node (MFN) of the three CSMs.
  • Nitrate: A glider with a Sea-Bird SUNA nitrate sensor will be deployed on the offshore “flux line”.

New Procurements

Several of the high-priority recommendations from the Innovations Labs that were deemed feasible for implementation required instrumentation that was not part of the OOI core. In this case, a formal procurement process is required (the process for replacing an obsolete sensor is similar). Four measurements required new instrument procurements: Near-surface velocity, phytoplankton imagery, particle size, and seafloor pressure. The procurement process for these instruments was initiated in November 2022.

The procurement process involves multiple steps of specification, information collection, review and approval before actual purchases are made. Among the first set of steps executed for the Pioneer MAB procurements were: consultation with a Focus Group of scientists external to the OOI, development of measurement specifications and revision of requirements as needed. The specifications were then used to create a solicitation of information from vendors through a broadly disseminated Request For Information (RFI). The RFI responses were reviewed by a selection committee composed of both internal and external subject matter experts, who evaluated instrument and vendor capabilities relative to performance specifications, technical feasibility, cost, and other factors. Additional steps included Design Reviews and Selection Reviews where the documentation of the process is presented to the Program Management Office and the NSF. After approval of vendor selection from the Review steps, orders were placed for the new equipment.

The Program is currently pursuing the procurement of four instrument classes, with 15 instances to be deployed at different locations within the Pioneer MAB Array (Table 1). Instrument locations include the buoy, Nearshore Instrument Frame (NSIF) and Multi-Function Node (MFN) on the Coastal Surface Moorings, and the buoy and buoyancy sphere of the Coastal Profiler Moorings.

Table 1: New Instrument Procurements for Pioneer MAB

Measurement OOI Code Make/Model Location Instances
Near-surface velocity profile ADCPU Nortek Aquadopp profiler 1MHz Coastal Profiler Mooring Sphere 5
Plankton Imaging PLIMS McLane Imaging Flow CytoBot Coastal Surface Mooring Central site NSIF 1
Particle Size Analysis PRTSZ Sequoia LISST-200X Coastal Surface Mooring   NSIF and MFN 6
Seafloor Pressure PRESF RBR Quartz3Qplus Coastal Surface Mooring MFN 3

More information on the proposed relocation of the Pioneer Array to the Mid-Atlantic Bight is available here.