Local researchers embarked on a 10-day mission off the coast of North Carolina to map the ocean floor. The new data may reveal areas where offshore wind energy development could occur with minimal impacts to sensitive fish habitats and ocean resources.
This week, the federal government allocated funding for wind energy projects off the coast of Rhode Island and Virginia. A wind project was recently announced in New Jersey that would construct five, 5 megawatt turbines off the coast of Atlantic City. In Oregon, five floating 6 megawatt turbines will be built in water over 1,000 feet deep. This renewable source of clean energy is gaining popularity and North Carolina may not be far behind. Research Ecologist at the National Ocean Science Lab in Beaufort Dr. Chris Taylor.
“North Carolina reportedly has some of the best conditions for wind in the southeast US. Our proximity to the Gulf Stream promotes relatively consistent strong winds that can have the potential for producing energy if utilized in the right way.”
This spring, North Carolina coastal scientists are involved in multiple projects exploring whether our coast is a good site for wind energy development. Researchers at the University of North Carolina at Chapel Hill’s Institute of Marine Sciences deployed two buoys between Cape Lookout and Cape Hatteras. Professor of Marine Sciences Harvey Seim says the buoys will collect information on water and atmospheric conditions in the Atlantic for one year.
“The intent here is to take a closer look at what the offshore wind energy resource is like and to carefully document its structure to help where and where not to consider deployment of offshore wind turbines.”
A local joint research effort to identify fish habitat and underwater resources in an area off the coast of Wilmington, near Cape Fear is taking place. Researchers are currently conducting a 10 day cruise aboard the 187 foot vessel Nancy Foster using high resolution hydrographic sonars to characterize reef structures and detail the topography of the ocean floor. Research Ecologist at the National Ocean Science Lab in Beaufort Dr. Chris Taylor says the resulting sea floor maps could reveal areas off the coast that would be possible sites for wind energy development.
"This particular mission, we’re hoping to survey about 120 benthic habitat stations. And we’re hoping to cover 75 square nautical miles of sea floor using the hydrographic sonar.”
Only 7% of the sea floor along the southeast United States has been mapped with modern sonars and through hydrographical surveys. The National Ocean Service, National Marine Fisheries Service, University of North Carolina, and the Bureau of Ocean Energy Management are partnering for the $1.4 million dollar project, which started in 2012. Finally, the conditions were favorable this week to launch the data collecting mission.
“We’re hoping for some good weather over the next seven to eight days. It’s involved a lot of planning both from our field workers. This cruise is going to involve a significant amount of objectives, we’re going to be mapping the sea floor so we needed to make sure that our sonar and our hydrographic and survey equipment was up and running correctly.”
Researchers will use high resolution hydrographic sonars that transmit sound through the water. The sound waves reflect off the ocean bottom and return to the equipment. With the technology, they’re able to determine the depth, the texture of the sea floor, and whether it’s rocky or sandy bottom. Dr. Taylor says the hard bottom habitats can provide critical support to important fisheries, such as snapper and grouper.
“We have a variety of sea floor types that host these benthic communities that support reef fishes that support the ecology and economies of our state. We don’t have a very accurate picture of the topography of these habitat types. We also know that some of these habitat types are different whether you move from on shore, to offshore into deeper waters or you move from north to south.”
Part of the research will be comparing the sea floor habitat data from the Cape Fear site with studies conducted off the coast of Morehead City and Beaufort. Hard bottom habitats may be at risk from impacts related to offshore energy development. Activities such as pile driving could harm sensitive benthic plants and animals. To gauge the impact on an area that potentially be developed for wind energy projects, divers will collect information on fish communities, benthic habitats and influence of sediment dynamics. Dr. Taylor says divers are used because they can make quantitative observations such as the specific species of fish, record accurate length measurements, and describe the types of habitats where the fish live.
“A team of very experienced divers here at the NOAA Beaufort Lab get in the water, and then determine using our eyes gathering the most and the highest level of detail in the water, describing what we see visually. The organisms on the sea floor, the benthic habitats, the biological communities that are on the sea floor including the sponges, the soft corals, the algae and then counting the fish.”
In addition to deploying divers to document ocean life and habitat, scientists will use a technological approach known as fisheries acoustics to get a better understanding of fish populations over a large area. Dr. Taylor says the equipment is similar to the hydrographic sonar, but instead of mapping the ocean floor, it uses sound to detect the number of fish at a specific location.
The Nancy Foster is set to return to Morehead City next Thursday. The findings, especially the sea floor maps, will be used in a variety of ways.
“Those maps will be provided to our colleagues at the Bureau of Ocean Energy Management with the intent that they would use these maps to consider refining the potential locations where wind farms might be developed. The goal is not to disturb or create any sort of impacts on these sensitive fisheries habitats. So identifying where these hard bottom habitats might be located would hopefully those areas would be excluded from development, the Bureau of Ocean Energy Management would take these maps into consideration.”
Dr. Taylor says they’ll also be providing information about the fish community and habitat types to minimize impacts to areas that may be considered for wind energy development. The information from the current research project at Cape Fear will be used for multiple projects, as many existing NOAA nautical charts use data collected in the 1970’s and even as far back as the 1940’s. We will continue to cover wind energy projects as they develop along the coast.