Chapter 3
Components of a Field Monitoring Program

Participants began the second day of the workshop by revisiting the discussion of example observational needs at the turbine and WEA scales before turning to the question of what components a field monitoring program could have in order to provide the desired observations. Reviewing the key issues that emerged from the first day’s discussions, many participants noted that critical questions remain unanswered at both the turbine and WEA scales, pointing to key observational needs. Speaking to the overarching question of how offshore wind farms impact regional biology, several participants highlighted the importance of determining how factors such as wakes, tidal mixing, and internal waves affect plankton aggregations, food webs, and whales’ foraging behaviors.

The purpose of making observations at the turbine scale is primarily to provide data for model development, rather than monitoring impacts at that scale, whereas WEA-scale observations are relevant for monitoring impacts as well as model development. At the turbine scale, a key question is whether turbulence caused by a single turbine or combination of turbines could have any effects on zooplankton patches or the nutrients and phytoplankton on which zooplankton depend. To answer this question, several participants reiterated the goal of studying atmospheric wakes with measurements both at the hub or turbine height and at the sea surface to develop vertical profiles of atmospheric heat flux and stability and to contextualize this information by documenting additional variables, such as how much power the turbine is generating when measurements are taken. For studying turbine-scale ocean wakes, observations on salinity stratification, temperature, current velocity, current shear, surface waves, turbulence, nutrient supply, and aggregations were discussed as particularly valuable. Process studies conducted on short timescales can help to understand and represent ocean wakes; some participants noted that these studies do not necessarily need to be conducted long term but could be repeated under different circumstances to observe how scour, stratification, corrosion, biofouling, benthic habitat, and other factors may affect turbulence and hydrodynamics.

At both the turbine and WEA scales, several participants reiterated that establishing baseline or control measurements would greatly help to characterize the hydrodynamic impacts of offshore wind infrastructure and determine whether these installations impact zooplankton patches and whale foraging. However, it can be extremely challenging to tease the impacts of wind turbines apart from the impacts of other natural or anthropogenic factors. To characterize WEA-scale hydrodynamic impacts, some participants underscored the suggestions to monitor water conditions before construction, during construction and operation, and after decommissioning, and to collect upstream, downstream, and cross-shelf measurements. Establishing temperature and salinity profiles at scales that span the baroclinic Rossby radius (2–10 kilometers); capturing stratification at a scale of 10 kilometers; and studying currents, surface wind, and the surface wave field were discussed as particularly useful approaches. Some participants also emphasized that measurements at the boundary layers including surface, mid-water, and bottom could be helpful. To identify the mechanistic connections between ocean physics and biology, concurrent observations of physical parameters and whales, zooplankton, and other species in the ecosystem could be beneficial. While recognizing that these observational goals suggest that a high level of investment may be necessary (and sustained), some participants also noted that existing data and instrumentation, such as from the previous Pioneer Array site, can be repurposed to facilitate this research.

Following this stage-setting discussion, participants divided into breakout groups to examine practical methods for capturing the measurements of the biological and ecological impacts of wind farms—especially for zooplankton—in Nantucket Shoals and the surrounding region.

BREAKOUT DISCUSSION HIGHLIGHTS: FIELD MONITORING COMPONENTS TO MEET OBSERVATIONAL NEEDS AT THE TURBINE SCALE

At the turbine scale, field monitoring includes two main tasks: (1) understanding hydrodynamic impacts on zooplankton and (2) calibrating, validating, and verifying LES-type models. Several participants noted that short-term process studies could be useful for collecting the data to improve models and inform the design and size of future wind energy projects.

Hydrodynamic data could be collected concurrently, with attention to variability and seasonality, and in the immediate area of the turbine foundation (around 2–10 rotor/monopile diameters) to measure stratification, velocity, surface wakes, ocean wakes (including their microstructures and TKE), tides, bottom turbulence, mixing, flow distortion, surface interactions, nutrient concentrations, zooplankton aggregations, and internal wave fields. For these measurements, some participants suggested collecting data during periods of 2–5 days with seconds-to-minutes resolution, noting that it is important to be able to account for foundation and turbine design and age, as well as wind events or atmospheric changes.

A range of measurement tools, platforms, and data collection approaches could be employed at the turbine scale. Dye releases could be used to understand how water flows around a turbine. Moorings attached to foundations in multiple places could support limited long-term observations, while fixed modular moorings could be deployed close together to gather upstream and downstream measurements. Echo sounders could be used to measure zooplankton patches, while mobile and fixed lidar sensors could be mounted in multiple locations and used to scan multiple directions. Additional tools include uncrewed surface vehicles, ADCPs, and high-resolution conductivity, temperature, and depth instruments (CTDs). The more data collection points there are, the more robust the analysis will be, although some participants noted that it will be challenging to reduce or eliminate noise between sensors and mitigate interruptions to existing radar systems. In addition, several participants reiterated the importance of minimizing the risk that instrumentation could entangle or otherwise harm whales and other wildlife.

Turbine-scale measurements may be combined or scaled up to understand WEA-scale effects, including mixing between turbines; several participants reiterated that hub height data can be correlated with sea surface effects. In addition, a participant noted that the techniques used by Duke University oceanographer James Hench to take fine-scale measurements could be employed close to turbines. Unresolved physical questions at the turbine scale include how best to measure internal wave dynamics, the optimal frequency of measurements, and whether existing instrumentation can capture it all or if additional tools are needed.

On the biology side, a baseline understanding of zooplankton patches and food web dynamics in the region can be used to determine whether ocean changes related to wind farms affect zooplankton aggregations. Some participants posited that zooplankton sampling may be best done at the WEA scale, but nutrients could be sampled at the turbine scale. Instruments and techniques relevant to biological sampling at the turbine scale include a combination of fixed and ship-based sampling; participants suggested acoustic surveys, VPRs, echo sounders (e.g., moored, upward-looking), targeted visual or passive acoustic monitoring surveys of right whale pods and feedings, eDNA analysis, and potentially whale tagging studies (where permitted). Sampling could occur both upstream and downstream from a turbine and from the ocean surface to the bottom, with fine-scale sampling to enable the detection of anomalies. Unresolved biological questions include the processes through which a zooplankton patch aggregates or disaggregates, how the nutrients may be affected, what baseline conditions exist when whales feed, and the spectrum of prey that whales consume.

BREAKOUT DISCUSSION HIGHLIGHTS: FIELD MONITORING COMPONENTS TO MEET OBSERVATIONAL NEEDS AT THE WEA SCALE

At the WEA scale, the main goal for the field monitoring program is to provide concurrent hydrodynamic and biological measurements to understand how biology

is affected by physics. Desired data for these studies—which, some participants noted, could be collected across large-enough timescales to account for monthly and seasonal changes—include measurements of internal waves, cold pool temperature and salinity structure, shelf break front position, larger-scale dynamic processes (e.g., storms), subsurface effects, zooplankton abundance and distribution, species composition at multiple depths, whale monitoring, bottom and surface boundary layer processes, and vertical ocean structures. These measurements would ideally take place both upstream and downstream from WEAs near Nantucket Shoals, stretching to the Mid-Atlantic Bight.

While it is difficult to establish true controls in the ocean, taking consistent and persistent observations to capture natural variability outside and inside WEAs can be helpful in facilitating comparisons. These data can be used to connect physical processes to ecology, specifically zooplankton aggregation, and to isolate WEA effects from other disturbances and interannual variability.

Taking large numbers of measurements consistently across large areas poses significant logistical challenges. Some participants suggested that a project could start with four to six fixed stations arranged in WEA corners near Nantucket Shoals or in stations upstream and downstream from turbines, at about 40–200 meters from a WEA, at Nantucket Shoals, and near its edge. This fixed-station data collection could be supplemented with an array of mobile, modular stations, such as boats (including commercial fishing boats), buoys, gliders, and benthic landers. These could be equipped with, capable of receiving input from, or supplemented by lidar, eDNA sampling, EK80 software, in situ imaging, x-band radar, tow nets, cameras, VPRs, high- or multifrequency acoustic echo sounders (pointed in multiple directions), infrared cameras, hydrophones, CTDs, thermistor strings, ADCPs, and other sensors. It may also be possible to place sensors on animals, although that approach has both unique benefits and drawbacks. To optimize the utility of the data for gaining insights into whale behavior and impacts, some participants suggested targeting sampling around areas frequented by whales. To minimize potential negative impacts, several participants also underscored the importance of considering effects from vessel or instrumentation noise, including during installation.

It may be possible to systematically and strategically use existing or retrospective data, such as from the Wind Forecast Improvement Project-3,¹ Ørsted,² Project Ocean W’aKEs, the Coastal Pioneer Array,³ and other lease areas to determine a baseline and simulate the vertical distribution of species composition to identify changes. In addition, modeling in advance of field efforts to determine what, where, and how to sample would increase efficiency and create a model–sample feedback loop to improve predictions, enable model–data comparisons, and identify hotspots or anomalies.

Several participants noted that while a major unresolved question at this scale is how to link physics and biology, additional important areas of focus for WEA-

___________________

¹ https://www2.whoi.edu/site/wfip3

² https://us.orsted.com/renewable-energy-solutions/offshore-wind/coexistence

³ https://oceanobservatories.org/array/coastal-pioneer-array/

scale studies include seasonality, whale behavior, and the hydrodynamic relationships between Nantucket Shoals and adjacent regions.

SYNTHESIS AND DISCUSSION

Jim Chen, Northeastern University, and Kaustubha Raghukumar, Integral Consulting Inc., provided a synopsis of their groups’ discussions of instrumentation, deployment strategies, and placement locations for field monitoring programs in Nantucket Shoals. Participants then expanded on these suggestions and explored possible next steps in an open discussion.

Participants in both groups reiterated the types of measurements that would be most helpful in elucidating impacts and informing modeling efforts, including data gaps relevant to resolving the vertical structures of both physical and biological parameters and atmospheric and wave wakes. While data from observations are clearly vital for developing and refining models, some participants also noted that models can be used to guide the implementation of observations. Given the complexity of deploying the diverse array of sensors and other data-gathering efforts needed, many participants stressed the importance of multi-institutional and multidisciplinary collaboration to share expertise and resources.

As planning and development of wind energy projects in the Nantucket Shoals region continue to move forward, time is of the essence in answering questions about their potential impacts, highlighting the importance of identifying and aligning existing observational efforts and facilitating work to compare and contextualize the data. A community-wide discussion among scientists, developers, regulators, and other stakeholders could help to identify partnership opportunities, priorities, and funding sources to coordinate and optimize new and existing research. Several participants emphasized that to be most effective, projects would ideally be well defined and realistic; some participants also stressed the importance of leveraging existing data and instrumentation and including data analysis costs in project budgets. In addition, some participants encouraged the community to follow FAIR data principles to maximize the value and future utility of data collection efforts.

Following the breakout session syntheses, participants considered how the workshop discussions might translate into a tangible research program. Participants discussed what level of detail is appropriate in determining research plans. While researchers generally write their proposals in response to a solicitation with some level of specificity in terms of the approach, scope, and budget, research funders may also benefit from input from researchers to understand what is likely to be most feasible and impactful. This points to the importance of clear and frequent communication among researchers, developers, government agencies, and other stakeholders in designing monitoring programs.

Morse stated that developers and regulators need a draft or general framework to begin moving forward while monitoring programs do not necessarily need to be fully detailed at their onset, Morse emphasized that the pace of development requires rapid action. She suggested starting with fixed moorings arrayed, for

example, in the corners of a lease area, one in Nantucket Shoals and two or three along the shelf break, with gliders constantly moving in between for long-term monitoring. She added that the plan could also incorporate data from temporary, mobile mooring systems for short-term process studies.

Kritzer agreed with Morse that a project of this scale and complexity needs a well-articulated sketch of an ambitious, comprehensive, cohesive, and modifiable plan to attract multiple funding opportunities that can be paired with BOEM or Integrated Ocean Observation System (IOOS) resources. While that is a challenging task in this short time frame, potential funders want to know what they are paying for and where coordination with existing programs is possible. For example, many workshop participants spoke of the importance of learning more about hydrodynamics at Nantucket Shoals and the shelf break. If consensus could be reached on what assets will take what measurements from what locations, that strong framing could attract significant funding, they suggested.

Kirincich highlighted the need to identify study parameters before drafting a plan, addressing details such as how long the program will last, what data are most needed, what funding is available, and what existing resources can be incorporated. In his view, taking an ad hoc approach and resolving details along the way are more challenging to coordinate or do well. He suggested creating a “laundry list” of study priorities and assets to start the process, and Nowacek agreed. Nowacek compared the process to creating a request for proposals (RFP) that specifies what measurements are needed but not how exactly they should be taken. Carpenter agreed with Kirincich that identifying a list of priorities could help move the process forward, even if those priorities are not fully specified. Kirincich suggested that a diverse range of participants could be included in such planning in order to coordinate and aggregate data and understand potential impacts from a broad perspective.

Jacqueline McSweeney, Stony Brook University, pointed out that it is hard to determine and prioritize the scope of observations to propose without knowing any details about what level of budget might be available to support this work. Tom Johnson, DHI Water & Environment, Inc., agreed, noting that the scale of the funding often determines what is possible. Yoko Furukawa, BOEM, wondered if both processes could happen simultaneously, with actionable but not prescriptive recommendations that BOEM can fund, start, and modify as needed with the help of experts and stakeholders. Kelly Oskvig, National Academies, agreed, suggesting that outlining initial details—for example, a plan for four moorings placed in two to three locations measuring temperature, salinity, and current, with BOEM as the initial funder—could help to lay the groundwork for the process studies, long-term monitoring programs, and the larger push for the types of resources some workshop participants highlighted as particularly important. Such a draft could also help to articulate the argument for why monitoring hydrodynamics is as important as monitoring biology, she added. Johnson agreed and suggested running simulations before deploying any instruments to understand what data or results will best signal impacts. That output could also be used to inform spatial and temporal sampling scales as well as a generalized study framework, with details to be added later.

Charles Mayo, Center for Coastal Studies, noted that from a biology standpoint, work needs to happen quickly to understand what drives right whale behavior and to establish a baseline needs to happen quickly, because these whales’ numbers have already dropped, and WEAs are being developed and built. He emphasized that the baseline is no longer a baseline as development has already altered the environment and stressed the urgency of the situation. Marsjanik agreed, adding that these are very difficult questions with multiple perspectives and stakeholders. She underscored the need for continued knowledge-sharing and collaboration. “Certainly, no individual one of us is the expert at all of this right? So we all have to compromise [and] work together to solve this problem within the resources that we have, and those are limited, but the most limited resource is time,” Marsjanik said. She said that in her experience, developers need plans that are practical and feasible, which is starting to happen, fortunately. She added that it would be extremely helpful for BOEM, NOAA, developers, and other funding entities to have a menu of options or a ranked list of priorities identifying the important questions across clearly identified scales.

Furukawa, Saba, Miles, and Lesley Thorne, Stony Brook University, discussed how BOEM could use the information in this proceedings to collaborate with other funders, such as the Department of Energy, NOAA, wind energy developers, and other stakeholders to execute a field monitoring program. Kohut noted that compromise, while challenging, can be important in turning discussions into actionable, flexible process study plans and larger-scale studies that reflect the comments and progress made during the workshop. Nowacek agreed, and Fratantoni emphasized the need for physical oceanographers to remain a part of the discussion, as the coupled physics–biology measurements are critical. Morse expressed optimism that this workshop and its forthcoming proceedings can be a powerful tool for bringing oceanographers’ and biologists’ voices to the table with regulators and developers. Nowacek agreed, and Glen Gawarkiewicz, WHOI, reiterated the urgency of these efforts, since the ecosystem is already undergoing major shifts, and the integration of physical oceanography and biology is critically important to elucidating potential additional impacts.

This page intentionally left blank.