Current Projects

  1. Collaborative Research: Riverine Carbon Contributions to Alaskan Arctic Coastal Margins. NASA Ocean Biology and Biogeochemistry Program Award #NNX17AI72G. In collaboration with researchers from Woods Hole and U. Alaska Fairbanks, this project seeks to better quantify seasonality and variability in riverine contributions of organic carbon into US Arctic Ocean coastal margins.

  2. Development of an Improved Model to Obtain Seawater Inherent Optical Properties from Ocean Color Remote Sensing. NASA Award #NNX15AQ53G. The goal of this project is to formulate and validate improved models for the estimation of seawater inherent optical properties from ocean color measurements.

  3. Quantifying the Spectral Absorption Coeffficients of Marine Phytoplankton and Non-phytoplankton Components of Seawater From In-situ and Remote-Sensing Measurements. NASA Ocean Biology and Biogeochemistry Program Award #NNX15AC55G. As members of the NASA PACE Science Team, our goal in this project is to improve both field and remote sensing estimates of the spectral absorption coefficient of seawater constituents.

  4. Scoping for Interdisciplinary Coordinated Experiment of the Southern Ocean Carbon Cycle (ICESCOCC). NASA Ocean Biology and Biogeochemistry Program #NNX14ADD86G. This is a “scoping” project to identify the key scientific questions, develop an initial study design, and make implementation recommendations for a future large-scale field project in the Southern Ocean. The long-term goal is to develop improved capabilities for monitoring fundamental carbon cycle parameters in this climate-critical region.

  5. Quantifying Sources of Optical Backscattering in Support of Remote-sensing Applications for Water Quality. NASA Terrestrial Hydrology and Ocean Biology and Biogeochemistry Programs #NNX13AN72G. The goal of this project is to quantify the role played by relatively large particles in regulating the magnitude and spectral behavior of the backscattering coefficient in coastal marine environments and inland water bodies where issues of water quality are particularly important. The approach consists of a combination of modeling efforts, experimental laboratory work, and field observations.

Recent Projects

  1. MRI: Development of an Instrument for Quantitative Characterization of Size Distribution of Aquatic Colloids. NSF Ocean Sciences Program Award #OCE 11-26870 (with additional matching funds from SIO). In this project we designed and fabricated a new instrument, based on tracking and analysis of particles undergoing Brownian motion, for quantitative determinations of the concentration and size distribution of heterogeneous colloidal assemblages (including nanoparticles) present in aqueous suspensions.

  2. SBIR Phase II: A Multi-Depth Underwater Spectroradiometer for Validation of Remotely Sensed Ocean Color and Estimation of Seawater Biogeochemical Properties. NASA Small Business Innovative Research Program Award #NNX11CH52P. In a second collaboration with OKSI, we developed a novel submersible instrument to provide simultaneous multi-depth measurements of the upwelling and downwelling radiative fluxes in the UV-VIS-NIR range with high spectral resolution.

  3. Optical Detection of Particle Concentration, Composition, and Size Within Arctic Waters. NASA Ocean Biology and Biogeochemistry Program Award # NNX10AG05G. We were part of a multidisciplinary NASA team (ICESCAPE; to address the impact of climate change on the biogeochemistry and ecology of Arctic seas. Our specific research goals were to explore the relationships between seawater optical properties and characteristics of the suspended particle assemblage (e.g. composition, size distribution), and to develop and apply inversion algorithms for retrieving biogeochemically-relevant information from optical remote sensing measurements. Two planned field expeditions in the Chukchi and Beaufort Seas were completed in the summers of 2010 and 2011.

  4. Assessing Biodiversity of Phytoplankton Communities in the Ocean from Optical Remote Sensing. NASA Biological Diversity Program Award #NNX09AK17G. This project had two major research components: (i) to utilize statistical models to characterize the diversity of phytoplankton communities within the open ocean utilizing ocean color data, and to assess the individual contributions of each community to global biomass and primary production, and (ii) to develop algorithms for estimating community composition from hyperspectral measurements of ocean reflectance and inherent optical properties. We participated in a major research cruise in the Atlantic Ocean during 2010.

  5. SBIR Phase II: A Miniaturized UV/VIS/IR Hyperspectral Radiometer for Autonomous Airborne and Underwater Imaging Spectroscopy of Coastal and Oceanic Environments. NASA Small Business Innovative Research Program Award #NNX11CA01C. This project was a collaboration with a commercial engineering company from Torrance, CA (Opto-Knowledge Systems Incorporated, OKSI) to design and develop a miniaturized hyperspectral radiometer with unique features (e.g. high spectral resolution over a broad spectral range) that is capable of deployment on unmanned platforms such as UAVs or UUVs.

  6. Carbon Dynamics in the Beaufort Sea from Field and Satellite Measurements. NASA Cryosphere Program Award #NNX07AR20G. The overall goal of this project was to develop ocean color algorithms suitable for mapping the spatial and temporal distribution of POC, phytoplankton, and inorganic particles within the Beaufort Sea region of the Arctic, and to utilize these measurements for developing a comprehensive description of the entire carbon cycle in this region. As part of this work, we participated in a multinational field expedition (MALINA; to the Mackenzie Shelf region of the Beaufort Sea under the auspices of the International Polar Year.

  7. Parallel Measurements of Light Scattering and Characterization of Marine Particles in Water: An Evaluation of Methodology. Office of Naval Research Award # N00014-05-1-0246. The goal of this project was to evaluate instruments for contemporaneous measurements of the optical volume scattering function and the particle size distribution of seawater, and to conduct laboratory and field measurements to examine natural variability in these parameters. Despite their fundamental importance to interpreting optical variability and particle dynamics, these quantities are rarely measured in the field.