Research project could help with oil spills

Posted: Monday, March 31, 2003

Mark Johnson made waves Saturday when he presented his upcoming research project at the Cook Inlet Aquaculture Associa-tion's annual meeting.

"The goal of the project is to investigate the dynamics of the water and ice in Cook Inlet using a high resolution numeric model, satellite tracked drifting buoys and satellite imagery," said Johnson, a physical oceanographer with the University of Alaska Fairbanks Institute of Marine Science.

The cost of this project is more than $940,000 and is expected to last more than three years. The satellite tracked drifting buoys -- commonly called drifters -- cost $2,400 each.

"The drifters are about the size of a beach ball and are connected to a beacon about 10 meters down," said Johnson. "We'll release 15 buoys a year for the next three years, 45 buoys total."

The drifters will lend to a major focus of the project, which is to identify and map linear zones of high current, commonly called tidal rips, in order to better understand when and where they occur.

The working hypothesis is that these rips are delineated by down welling slicks and up welling chop. This often is where incoming salty water is meeting outgoing water that is less salty. The belief is that the vertical structure of the rips migrates horizontally with the ebb and flow of the tide.

Therein lies one of the biggest challenges to conducting the research: the complex nature of the Cook Inlet tidal regime.

"Cook Inlet has the second highest tidal range in the world," Johnson said.

This is a problem in numeric modeling in that boundaries can be 100 meters long, as opposed to most other places where the difference between high and low tide is typically only a few feet at most. The existing models simply weren't designed to compensate for a body of water as extreme as Cook Inlet.

So what's the importance of learning about this rips? Quite a bit, according to Johnson, since sediment, debris and contaminants will come together at these rips.

"Information from the study will, hopefully, predict zones of significant sediment transport along the floor of the inlet," he said. "This would have application to selecting safe locations for oil and gas platforms and pipelines, as well as telecommunications cables."

However, this isn't the only benefit of the study to the oil industry.

"Should an oil spill occur, these studies will forecast where the oil will go and how it will move, which may allow better positioning of cleanup equipment," he said.

The fishing industry will benefit from the study, as well, Johnson said. Fish often will hang out in the rips, so fishers may want to know rip locations. Although, since debris as large as trees can get into the rips, some fishers may want to steer clear of those locations.

In any case, Johnson said he hopes for support from the fishing community, which is one of the reasons he presented his project to CIAA.

"We want to keep fishermen up to speed and ask for their help," Johnson said. "We want people to know what the drifters look like so they will leave them in the water, or call the number stenciled on the buoys side if beached."

Although some of the fishers attending the meeting seemed concerned about the inconvenience of getting one of the drifters caught in their nets, most seemed to acknowledge that oil spills are a lot more inconvenient to their fishing, and the more that can be done to prevent them, the better.

Subscribe to Peninsula Clarion

Trending this week:


© 2018. All Rights Reserved. | Contact Us