General themes
- Oceanic biogeochemical processes mediated by organic and inorganic particles in open ocean, coastal, near-bottom, and extraterrestrial environments
- Validation and application of novel observational methods for marine organic matter
- Autonomous platforms for ocean observations
- Ocean color remote sensing
- Interactions of emerging contaminants with ocean biogeochemical systems.
Explore the tabs at left for examples of current and recent research projects
We collected field observations to characterize the strength and variability in the ocean’s “biological carbon pump” across contrasting sites in the ocean, using a flotilla of sediment traps, cameras, and innovative sampling techniques. The observations are supporting development of remote sensing-driven models to predict the ocean’s biological carbon uptake. The EXPORTS program is a large, interdisciplinary and multi-institutional effort supported by the NASA Ocean Biology and Biogeochemistry program.
The ocean naturally moves carbon produced by living organisms from the atmosphere to deep water, and this plays an important role in how Earth’s climate may respond to increasing amounts of carbon dioxide. Additionally, some have proposed attempting to intentionally accelerate this process in an effort to reverse human carbon dioxide emissions. However, teasing apart the different biological influences that drive sinking carbon remains a major challenge. The tools that are required to measure sinking carbon are often expensive and specialized, limiting their accessibility. In this NSF-OTIC funded project, a camera-equipped sediment trap that catches and identifies sinking particles will be developed, tested, and refined. It will utilize openly shared software, and hardware designs that are based upon commercially-available components, to enable easier adoption by other researchers.
How might the optical signatures of ocean microbes be used to detect life beneath the ice-covered seas of Jupiter and Saturn’s moons? The spatial distribution of life in the hidden oceans below the ice on “ocean worlds” beyond Earth is not likely to be uniform, but rather clustered near sources of energy and chemical gradients such as water-ice boundaries, seafloor hydrothermal vent sites, and critically, at the surfaces of solid particles in the water. In this project, supported by the Hypothesis Fund, we are using modeling and laboratory measurements to answer the following questions: 1) How should underwater, active optical sensors be optimized to rapidly characterize particulate biological signatures on ocean worlds beyond Earth? and 2) What oceanic environments on Earth are the closest analogs, in terms of their inherent optical properties, to oceans elsewhere in our solar system?
What happens to plastic waste after it gets into the ocean? Evidence shows that it gets broken down into smaller and smaller pieces (“micro-plastics”). With support from the University of Maine MARINE Initiative, master’s student Mikayla Clark investigated whether sinking aggregates of organic detritus might carry microplastics down into deeper water, affecting the fate of plastic waste in the ocean.
In partnership with Sequoia Scientific (www.sequoiasci.com) and with funding from the NSF Small Business Technology Transfer program, we designed a sensor for the detection of sinking particulate carbon in the ocean, which is a key pathway in the ocean’s biological carbon cycle. The sensor was designed from the ground up for use with distributed, autonomous profiling floats.
Maine’s coastal waters contain a rich mix of phytoplankton, marine organic matter, suspended particles. With NASA EPSCoR support, we explored links between the light-absorbing and scattering properties of colloidal matter in our local estuaries, and the information about water quality that can be retrieved from satellite imagery such as the example shown here.
