Surrounded by the mountains of landlocked Tennessee, Oak Ridge National Laboratory’s Teri O’Meara is focused on understanding the future of the vitally important ecosystems lining the nation’s coasts.
She brings biogeochemistry expertise and experience conducting research in the salt marshes of Maryland, the maritime forests of North Carolina and the tidal flats of New Zealand to the challenge of improving how global climate models represent coastal ecosystems.
“Our coastal ecosystems perform so many critical services,” O’Meara said. “They are also incredibly beautiful and increasingly endangered.”
With more than 95,000 miles of coastline in the United States alone, the landscape is vast, varied and vulnerable to natural and human-induced changes. Ecosystems such as estuaries, bays, mangroves and wetlands serve as a buffer zone between land and sea. They filter out pollutants, act as nurseries for many types of fish, limit erosion and play a significant role in carbon storage.
These ecosystems are struggling under a variety of pressures, including sea level rise, storm surges and land development. O’Meara’s research aims to better reflect these dynamic ecosystems in predictive models, which can help leaders examine future scenarios and take action.
As a staff scientist at ORNL with a joint appointment through the Smithsonian Environmental Research Center, O’Meara brings a natural curiosity and a love of solving puzzles to her research. She enjoys seeking answers both big and small.
“I want to know everything about everything,” O’Meara said. “If you only focus on one process or subset of processes, you can miss the big picture.”
Making connections is at the heart of O’Meara’s work. She collaborates with both modelers and field scientists as part of a multi-laboratory Department of Energy project called Coastal Observations, Mechanisms and Predictions Across Systems and Scales, or COMPASS. She feels lucky to be part of such an integrated effort.
“If what you're trying to create is a mechanistic representation of the big picture, then you need to measure how all these processes — biogeochemistry, hydrology, ecology — interact with each other,” O’Meara said. “Because COMPASS includes partners spanning so many disciplines, it allows us to collect a variety of data to get a much clearer picture of how those processes all connect to each other.”
Where water meets land
Examining the interactions that happen in the transition zones between land and water has been a current running through O’Meara’s work since her undergraduate studies. But it was an internship the summer after high school that sparked her passion for marine science.
When O’Meara embarked on her first research opportunity at the age of 17, she interned with Chicago’s Shedd Aquarium, which included two weeks living aboard a research vessel in the Bahamas. There, she spent her days in the surf, gathering data for a project comparing the species of mollusks living on the windward and leeward sides of an island.
That fall she continued her pursuit of science at Hope College in Michigan. She began school with the idea of becoming a veterinarian but found that fetal pig and rat surgeries were not her speed. She took a wide variety of science classes, seeking the right fit. She flung her net widely and completed college with two separate degrees in biology and chemistry, just a few credits shy of a third in geology. This interdisciplinary mix has proven pivotal to her career.
It was her cross-disciplinary focus that landed O’Meara an undergraduate research assignment in the geology department working on a chemistry-based project the summer after her freshman year. The research focused on the fate and transport of pharmaceuticals, such as antibiotics, in groundwater – the topic of O’Meara’s first published paper.
O’Meara went on to obtain her doctorate from the University of North Carolina at Chapel Hill in environmental science and engineering with an emphasis on marine science. Her thesis focused on the influence of nutrient pollution and other human impacts on coastal ecosystems.
She headed to New Zealand next, where she spent three years as a postdoctoral fellow at the University of Auckland, applying her knowledge of biogeochemistry to a coastal ecology project and teaching students. Field work on the North island gave her the opportunity to explore a very different landscape from the U.S. coastlines that suffer from an overabundance of nutrients, such as nitrogen, from diverse sources, including industrial pollution and fertilizer runoff. In New Zealand, the near-shore waters have the opposite problem: Nutrients are scarce.
“It basically felt like working on the moon,” said O’Meara. “These big open sand flats look like there’s nothing there. But if you really get close, there’s a thin layer of snot-like algae that covers the sand and supports all kinds of life. The area just below the surface is teeming with all sorts of creatures.”
O’Meara studied the ways that animals such as worms the size of a thumbnail “bulldoze through that mucus layer” and have a dramatic effect on the biogeochemistry of the landscape. The experience prepared her for examining the many large and small influences on coastal systems back home.
She returned to the United States for a postdoctoral fellowship with the Smithsonian Environmental Research Center focused on modeling coastal habitats. The position was based at ORNL due to the laboratory’s expertise with Earth system models and for easier collaboration with a key advisor, Peter Thornton, who leads the Earth Systems Science section.
“I started that job with zero experience in modeling, but I learned a lot along the way with the help and patience of some very wonderful people at Oak Ridge,” O’Meara said.
Her experience with coastal systems proved invaluable as the COMPASS project launched, and O’Meara accepted an invitation to join the project team, becoming ORNL staff in March 2021.
Modeling coastal complexity
The COMPASS team is addressing a gap in computational models, such as the DOE Energy Exascale Earth System Model, or E3SM. These models do not currently capture the dynamic exchanges that happen between the land and water. O’Meara likened the E3SM representation of the coast to a land box and a water box with an arrow pointing from the land to the ocean. The reality is much more complex.
The tides create ebbs and flows in the water levels, plant roots inject oxygen into the soil and animals move nutrients between sand and sea. Microbes thrive in tiny pockets with and without oxygen and plants get buried in the sediment. Textbook concepts about orderly layers of chemical reactions get churned up with the surf. These factors affect how carbon moves through the system and how much is stored or released into the atmosphere, influencing climate change.
To tackle this complexity, O’Meara is modeling a tiny slice of the system. Working with a one-dimensional model, she is focused on capturing the most important chemical reactions happening in a single column of water between the sediment and the surface. Her results can then be scaled to the larger model.
O’Meara is also acting as a bridge between modelers and researchers in the field collecting data. She finds a lot of satisfaction in the integrative, interdisciplinary work. “I really feel like I’m hitting my scientific stride with the work I’m able to do at ORNL,” O’Meara said.
“I’m excited that DOE cares enough about the big picture to have these huge projects where you have all these experts in different fields that you get to work with and learn from,” she continued. “The breadth of expertise gives you an opportunity to expand out and see how all those connections fit within the system. That's something that really drew me to Oak Ridge.”
UT-Battelle manages ORNL for the Department of Energy’s Office of Science, the single largest supporter of basic research in the physical sciences in the United States. The Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit energy.gov/science.