CORVALLIS - An Oregon State University-led research team is conducting a major project off the Oregon coast this summer to learn more about the complex, even mysterious forces that move ocean waters, life forms and debris between the shoreline and deeper waters.
The findings will be critical, with implications for fisheries management, pollution control, coastal tourism, shipping, invasive species, and other issues.
The researchers are working under a five-year, $9 million grant from the National Science Foundation.
"A great deal is known about the currents off the Pacific Coast that transport water and sand in northerly and southerly directions," said Jack Barth, a professor of oceanic and atmospheric sciences at OSU and one of the study's principal investigators. "Much less is known about the transport of waters across the continental shelf.
"How do things move in an east-west, or a west-east direction?" he added. "Obviously, wind is a key factor, but so are the topography of the ocean floor, temperature and weather."
The importance of a better understanding of these processes was illustrated during the aftermath of the sinking of the New Carissa off Coos Bay, said Mark Abbott, dean of OSU's College of Oceanic and Atmospheric Sciences. Hundreds of gallons of oil leaked from the vessel and, despite a number of sophisticated models on currents and wind, the oil showed up on beaches and in estuaries in places that surprised people.
"There were a lot of uncertain predictions surrounding the New Carissa," Abbott said. "We need more baseline data and a better understanding of the off-shore processes."
That's where the OSU study comes in. Called "COAST," or the Coastal Ocean Advances in Shelf Transport, the interdisciplinary research project will join ocean chemists, biologists, physicists and others in a complete--- and very visible --- study of the waters off the Oregon coast. During the next few weeks, scientists aboard the research ships Wecoma, Thomas G. Thompson, and Elakha will measure water temperatures, salinity, turbulence, zooplankton fields, wind velocity, and rate of upwelling.
The researchers also will fly a SENECA III aircraft over coastal waters, dropping in temperature probes that will give them an instant profile of temperature variations, and collect data that will help them profile the atmosphere and its boundary with the ocean below.
In mid-August, they will conduct an experiment using dyes to watch how extensively and rapidly ocean waters move at different depths. "There is an assumption that if you take something out to the deep ocean and dump it, it will stay out to sea," Barth said. "Ships, for example, have to be a hundred miles out of port to dump ballast water to keep invasive species and pollutants out of our bays. But do we know how far in toward shore those waters can go?
"You might be surprised," he added. "I've tracked water that's moved 150 miles."
The COAST project also will focus on the movement and health of phytoplankton blooms that are critical to the ocean food chain - and help absorb carbon dioxide from the air. The Pacific Northwest is beginning what appears to be one of the best salmon seasons in recent memory and the health of these phytoplankton masses is one of the keys to that success.
Yet scientists are still unclear as to what factors influence the upwelling that provides the nutrients that keep the whole system vibrant. One of the newest theories in the scientific community is that iron stimulates phytoplankton growth, and there have been suggestions that injecting iron into phytoplankton fields would boost productivity and help absorb more carbon dioxide.
"Most of the iron comes from river runoff and it varies along the coastline," said Patricia Wheeler, an OSU professor of oceanic and atmospheric sciences, who also is a principal investigator in the study. "Knowing more about how river water moves out into the ocean will give us a better picture on how phytoplankton might be affected."
There are other considerations, Abbott points out.
"A lot of the iron is a product of industrial runoff, and the idea that companies may be able to discharge their effluent --- and possibly get a credit or tradeoff, a la the Kyoto Accord --- has some of these folks kind of excited," Abbott said. "The whole thing is a bit premature."
The OSU researchers are working with colleagues from the University of North Carolina and the Lamont-Doherty Earth Observatory on the COAST study. Much of the major fieldwork will be done this summer and in 2003 in cooperation with the national Coastal Ocean Processes "CoOP" program.