Geographers study Katrina’s effects on ocean floor

East Carolina University researchers are evaluating the effects of Hurricane Katrina on the ocean floor in the Gulf region.

As part of a $150,000 National Science Foundation grant, nine ECU Geology and Coastal Resources Management faculty members and students will arrive in Louisiana next week to study how the hurricane shifted sediments, nutrients and chemicals in the Mississippi and Atchafalaya deltas. The data will provide new insight into seabed disturbances, which has important implications for geochemical and biological processes. Also, observations may help future evaluations of where to place pipelines and other infrastructure to best avoid harm from storms and other acts of nature.

“The recent crossing of Hurricane Katrina offers an unprecedented research opportunity and the potential to draw something positive from this catastrophic event,” said Reide Corbett, a professor in geology, who is conducting the study along with ECU professors J.P. Walsh and David Mallinson.

The grant, which was recommended for funding this week, is for a two-year study of the deltas and adjacent continental margin. The ECU team is collaborating with faculty from Oregon State and Tulane universities.
For 10 days researchers will work aboard the research vessel Hatteras, a 135-foot University-National Oceanographic Laboratory System ship operated by the Duke/University Marine Laboratory. The scientists hypothesize that major weather events like Hurricane Katrina, which was a Category 5 hurricane when offshore, have a disproportionate role in the destabilization and redistribution of sediments and chemicals in the coastal waters of Louisiana.

The professors will study how sediments move within the deltaic system in short amounts of time. The movement and storage of sediments and nutrients – such as carbon and oxygen – along continental margins can have several effects on the environment, including the cycling of carbon dioxide between the ocean and atmosphere. The increase of carbon dioxide levels in the atmosphere has been associated with global warming.

“We will look at how organic-rich sediments move in the system,” Corbett said. “The question is: How and where do these sediments move in a short amount of time? Previous data suggests that the materials move fairly quickly into deep waters, but there is little to no information on the transport of these materials during such a significant weather event.”

Such processes have important implications for the fate of material from land in the ocean, and ultimately, the interaction of the ocean and the atmosphere.