Grace Chang, Ph.D.

Senior Science Advisor, Director of Research and Development

Bio
Relevant Experience
Education & Credentials
Insights & News

Bio

Dr. Grace Chang has more than 25 years of experience in the fields of limnology and oceanography. Dr. Chang has managed programs involving field operations, data processing and analysis, and numerical modeling for environmental characterization, observational monitoring, scientific research, and technology development in support of marine renewable energy, hydrodynamics and sediment transport, and oceanographic research programs. She is recognized for her continued advancement of analytical methods in hydrodynamics and particle characterization through optics and acoustics, as well as for environmental research and monitoring. Dr. Chang has more than 40 peer-reviewed publications and frequently is invited to review materials for professional journals and national funding agencies.

Relevant Experience

R&D

SEABIRD: System for Environmental Assessment of Bird/Bat Interactions with Real-time Detection, California — The primary goal of the SEABIRD project is to advance bird and bat monitoring technology to address critical knowledge gaps in collision risk models and allow wind energy proponents to avoid or minimize detrimental scenarios of high collision risk uncertainty. This project’s multisensor monitoring framework will improve the accuracy and efficiency of wind energy assessments to support regulatory processes, conservation efforts, and sustainable wind energy development.

OPTically-based In-situ Characterization System (OPTICS), United States — Primary inventor of OPTICS, a system for characterizing surface water chemical contamination. OPTICS combines robust aquatic instrumentation and innovative data processing techniques to produce high-resolution measurements of dissolved and particulate concentrations of a wide range of contaminants at a significantly reduced cost. OPTICS has been validated and demonstrated at multiple contaminated sediment sites and shown that the system provides low-cost, high-resolution, time-series measurements of PCBs, heavy metals (mercury and lead), and other contaminants of concern (e.g., DDx, TCDDs, and copper).

Rapidly Deployable Acoustic Monitoring and Localization System Based on a Low-Cost Wave Buoy Platform — As co-inventor, developed a cost-effective, compact array of acoustic vector sensors, NoiseSpotter^®, that characterizes, classifies, and provides accurate location information for anthropogenic and natural sounds in support of environmental monitoring technologies to evaluate the impact of marine and hydrokinetic energy devices.

Real-Time Wave Assessment Tool — As co-principal investigator, developed an ocean wave buoy capable of measuring and wirelessly relaying real-time wave data in support of the design, siting, and performance optimization of ocean energy conversion systems. This project resulted in the commercialization of the Spotter wave measurement buoy.

Renewable Energy

Consultant Report in Support of California Senate Bill (SB) 605 (Wave and Tidal Energy), California — Contributed to the consultant report that supports the California Energy Commission’s 2024 Integrated Energy Policy Report. Authored several chapters of the Phase 1 (Feasibility, Permitting, and Economic Development) and Phase 2 (Identify Sea Space and Least Conflict Areas for Wave and Tidal Energy) consultant reports for SB 605.

A Numerical Modeling Framework to Evaluate Effects of Offshore Wind Farms on the California Upwelling Ecosystem — Studying the potential effects of California offshore wind turbines on the wind stress field, upwelling circulation, and biogeochemical responses for a number of baseline (no wind farms) and modified (simulated wind farms) scenarios using highly resolved coupled numerical models (atmosphere-ocean circulation). Upwelling index metrics are being computed to quantify changes in upwelling resulting from offshore wind turbine deployment. Ocean circulation results indicate that net upwelling in a wide coastal band changes relatively little; however, the spatial structure of upwelling within the coastal region of a wind farm can be shifted. Results for biogeochemical effects are pending.

Empowering Communities with a Multi-Use Decision Support Dashboard to Participate in Marine Renewable Energy Planning and Development, United States — Collaborated with community organizations to engage community members to guide development of a user-friendly dashboard to give stakeholders a data-driven voice in the marine renewable energy (MRE) planning and development process. The dashboard enables interactive visualization and synthesis of multiple layers of ocean use data to promote meaningful stakeholder engagement and communications, and informed and inclusive decision-making, and will be a significant advancement in ocean multi-use management with MRE.

Overcoming WEC Grid Integration Challenges: Coupling Wave Forecasting, WEC Array Controls, and Power Production, Yakutat, Alaska — Implemented machine-learning methods for optimization of wave data assimilation modeling to improve wave forecasting. Accurate wave forecasts were integrated with wave energy converter (WEC) farm operational controls and energy storage systems to increase certainty in power forecasts. The “complete” power forecast will balance energy variability on grids for energy resiliency and security.

Improving the Efficiency and Effectiveness for Marine Hydrokinetic Permitting: A Toolkit and Engagement for Success, United States — Developed an easily accessible online toolkit that integrates relevant regulatory, scientific, and spatial marine energy data to increase regulators’ understanding of marine energy projects, devices, and their potential environmental impacts while reducing permitting time and costs of marine energy projects. Conducted in-person meetings and webinars with relevant regulators from federal and state agencies to share and gather input on the toolkit and share experts’ understanding of potential impacts and the state of known/unknown science for marine energy projects.

Marine and Hydrokinetic Energy Market Acceleration and Deployment, Environmentally Focused, Kaneohe, Hawaii, and Santa Cruz, California — Performed numerical modeling of the effects of nearshore wave propagation in the lee of WEC arrays. Performed sensitivity analyses of numerical wave models to offshore wave conditions, model parameters, and WEC characteristics. Executed wave models over various offshore wave conditions for evaluation of nearshore wave propagation in the presence and absence of modeled WECs.

Model Validation and Site Characterization for Marine Energy Sites, Multiple Sites — Assisting multiple clients with high-fidelity wave and tidal resource characterization at potential wave and tidal energy sites. Performed comprehensive wave and tidal energy resource assessment using numerical modeling and geospatial tools and techniques. Managed field data collection of high-quality wave resource and water column current data. Characterized suspended particle load (particle concentration, size, and composition) at a potential tidal energy site to inform a regional circulation model and to enable industry to design devices best suited to resist the abrasive and intrusive stresses of suspended materials.

Contaminated Sediments

OPTICS Implementations for Remedial Investigation, Baseline Assessments, Source Identification, and More, United States — Developed, validated, and commercialized OPTICS, a high-resolution chemical contaminant characterization system. OPTICS demonstrations include determining high-resolution surface water contaminant concentrations to quantify fluxes and mass transport of heavy metals, PCBs, pesticides, and other surface water contaminants to support numerous tasks, including providing baseline information with which to measure potential changes in water quality after adjustments to a Superfund site (e.g., carp management) are made; establishing baseline criteria and resuspension engineering performance standards for dredging and capping activities; determining and quantifying mechanisms of redistribution of heavy metals to support remediation efforts; and identifying, quantifying, and characterizing sources and transport mechanisms of surface chemical contaminants at multiple Superfund sites. Demonstrated OPTICS as a cost-effective, long-term monitoring method for chemical contaminants in surface water and evaluated the utility and cost-effectiveness of the technology compared to traditional sampling methods (supported by the Environmental Security Technology Certification Program).

Berry’s Creek Study Area, Sediment and Contaminant Transport Investigation, New Jersey — Obtained field measurements and performed data analysis for development of a quantitative description of the hydrodynamics and sediment transport in the system, in support of risk analysis and remedial selection and design. Calculated site-wide sediment flux and solids mass balance using measurements of currents and sediment concentration derived from acoustical and optical measurements. Developed a suite of instrumentation for measuring bottom shear stress and particle characteristics using acoustical and optical methods.

Evaluation of Environmental Dredging for Remediating Contaminated Sediments in the Ashtabula River, Ohio — Characterized the environmental dredge plume using moored and mobile field measurements. Mapped the extent of the dredge plume using a novel sediment gradient approach. Quantified the volume of the dredge plume and the total mass of dredge sediment released into the water column during dredging activities. Related sediment concentration to concentrations of contaminants of potential concern to estimate the mass of contaminants released during dredging.

Contaminated Sediment Transport in the Kalamazoo River, Michigan — Characterized key regions of sediment deposition based on river characteristics, flow, and sediment loads along the Kalamazoo River to assess sediment trapping efficiencies.

Conceptual Site Model Delineation of In-Water Site Boundary, Port Angeles Harbor, Washington — Obtained hydrodynamic field measurements and performed numerical modeling to support contaminant fate and transport investigations. Executed a numerical wave model and validated results with measurements to assess the potential for sediment resuspension and transport during standard and extreme environmental conditions.

Sediment Transport Analysis at the United Heckathorn Superfund Site, Richmond, California — Developed a sediment transport conceptual site model from field and analytical results to address sediment management questions. Determined the magnitude and frequency of sediment resuspension and the magnitude and direction of sediment flux from analysis of field data.

Environmental Monitoring

Environmental Monitoring and Analysis in Support of Port of Bunbury Dredging Activities, Koombana Bay, Western Australia — Calculated water column suspended solids concentration from acoustical and optical measurements to establish background and exceedance levels of total suspended solids concentration at monitoring and reference sites during Port of Bunbury Inner Harbour dredging activities. Performed analysis of solids variability as related to physical forcing processes to ascertain potential sources of elevated solids. Utilized a combined current and wave bottom shear stress model to help determine sediment stability of a proposed dredge material disposal site and validated the model with SEDflume laboratory results.

Currents, Waves, and Suspended Sediment Monitoring, Baker Bay, Washington — Monitored water column and near-bed currents, surface waves, and water quality at seven different sites in Baker Bay, Washington, over a 6-week period to estimate sediment accumulation in Baker Bay, as well as sediment shoaling in two important navigation channels, Ilwaco and Chinook Channels, to aid the U.S. Army Corps of Engineers in determination of dredging needs in the region.

Oceanography

Using Population Genetic Models to Resolve and Predict Dispersal Kernels of Marine Larvae, South Pacific Ocean — Co-principal investigator on a National Science Foundation project to develop data-assimilated biophysical models of larval dispersal using isolation-by-distance (IbD) theory to estimate mean parent-offspring distance for reef fish species at three isolated South Pacific archipelagos, determine the relative role of species traits and seascape characteristics in shaping larval dispersal kernels, develop a conservation framework to design managed area networks that capture temporal variability in larval dispersal over many generations, and engage with local stakeholders in each archipelago to implement the newly developed approach.

Improved Observation and Parameterization of Bottom Boundary Layer Turbulence and Particle Properties, San Francisco Bay, California — As co-principal investigator, used novel acoustical and optical instrumentation and laboratory-based sediment experiments deployed in wave-driven estuarine waters of San Francisco Bay to directly observe relationships between physical dynamics and biogeochemical properties of suspended particles. The field and laboratory results are used to inform a large-eddy simulation model that resolves high-resolution variability of the turbulent, sediment-laden boundary layer. This work was funded by the National Science Foundation (NSF).

Nearshore Sound Propagation of and Species’ Response to Active-Source Seismic Surveys, Offshore Oregon, United States — As co-principal investigator, measured the particle motion component and pressure amplitude variations of the acoustic disturbance from seismic survey explosions along the Cascadia Subduction Zone. High-intensity acoustic pulse information is correlated with behavioral responses of fishes and invertebrates in the Redfish Rocks Marine Reserve using acoustic telemetry, tracking, and acceleration of tagged animals. This project is funded by the NSF.

Adaptive Mapping of the Hypoxic Zone, Gulf of Mexico — Served as co-principal investigator to develop enhanced autonomous hypoxia mapping capabilities for surface, subsurface, and near-bottom waters of the Gulf of Mexico and other water bodies affected by hypoxia.

Prediction of Optical Variability in Dynamic Nearshore Environments, Santa Cruz, California; Waimanalo, Hawaii; and Duck, North Carolina — As lead principal investigator, developed a system for forecasting marine optical conditions in the surf zone and nearshore coastal ocean using field measurements, analytical methods, and numerical modeling.

Radiance in a Dynamic Ocean (RaDyO): Radiance and Visibility as Affected by Inherent Optical Properties, and Imaging System Performance and Visibility as Affected by the Physical Environment, San Diego and Santa Barbara, California — Led and co-managed a team of principal investigators in an investigation of the sources of variability of optical properties for the interpretation of images from underwater electro-optical systems. Determined sources of variability of underwater visibility, including upper ocean mixing from wind forcing and stratification, as well as eddy-induced phytoplankton blooms.

Multidisciplinary Ocean Sensors for Environmental Analysis and Networks (MOSEAN), Hawaii and Santa Barbara, California — Acted as project manager to develop, test, and validate new sensors that are capable of sampling biological, chemical, and optical variables and demonstrated new interdisciplinary sensor suites for use with a variety of autonomous, unattended, stationary and mobile sampling platforms in coastal and deep ocean environments.

Southern California Coastal Ocean Observing System (SCCOOS): Shelf to Shoreline Observatory Development, Santa Barbara, California — As lead principal investigator and SCCOOS Mooring Working Group member, managed and participated in the development and operations of a real‑time interdisciplinary mooring platform deployed in 80 m of water on a shelf break. Researched the delivery of nutrients, particles, and pollutants from offshore to the nearshore coastal ocean.

Education & Credentials

Ph.D., Marine Science, University of California, Santa Barbara, California, 1999

M.S., Mechanical and Environmental Engineering, University of California, Santa Barbara, California, 1997

B.G.E., Geological Engineering, University of Minnesota, Minneapolis, Minnesota, 1995

B.S., Geology, University of Minnesota, Minneapolis, Minnesota, 1995

Continuing Education

OSHA 40-Hour HAZWOPER

OSHA 8-Hour HAZWOPER Refresher

Professional Affiliations

Member of The Oceanography Society

Member of American Energy Society

Member of Marine Technology Society

Insights & News

Posters

SEABIRD: System for Environmental Assessment of Bird/Bat Interactions with Real-Time Detection