NeMO September 3, 2003

Logbook: September 3, 2003

45° 56.0' N, 130° 0.8' W
Air temperature 60°F, 2000 PST

Dive R740, which was focussed on biological experiments and sampling, came to an end at 1900 PST. Larval settlement arrays that were deployed at ASHES vent field for the last year were retrieved. These arrays attracted larvae that settled and grew on them since last year. The arrays will provide insight about spatial and temporal variability regarding the settlement and recruitment of vent invertebrates. In addition, digital video and digital still camera surveys of sulfide worm behavior at Hell vent were performed. The focus of the photo/video surveys was to observe feeding behavior and the territoriality of the worms. ROPOS proceeded to the east side of the caldera and examined the 'limpet racetrack' experiment that was deployed earlier on this expedition. Another experiment was recovered north of Marker-33 vent. For this experiment, wood was left on the seafloor for the last year to study the burrowing clams that use wood as a habitat. It is remarkable that species specifically adapted to live on wood can be found out here, so far from the continent. The wood will be analyzed, focussing on the population and molecular biology of the clams as well as species richness and diversity. ROPOS is back on deck. This evening, two Bottom Pressure Recording (BPR) moorings were deployed, and at present a CTD cast is taking place. ROPOS is scheduled back in the water at midnight for Dive R741, a fluid-sampling dive on the 1998 lava flow.

Cruise Calendar

Aug/Sep 2003

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Wood that was left on the seafloor for the last year to study the burrowing clams that use wood as a habitat. A spider crab seems interested in the experiment as well.

Teacher's Report
Bill Hanshumaker, Educator at Sea

Researcher Interview:
Jon Bumgardner
Mechanical engineer
NOAA Pacific Marine Environmental Laboratory
B.S. in Mechanical Engineering (2001), University of Washington

PMEL engineers and UW chemist atop the RAS. Left to right: Jon Bumgardner - PMEL (see interview), Dave Butterfield - UW/PMEL chemist, Nick Delich - PMEL, John Shanley - PMEL.

Bill:
When you started in college, was this what you thought you would do?

Jon:
Absolutely not! I thought that I would end up in a design firm or big factory in the automotive industry or aerospace. But I had a real interest in designing oceanographic equipment.

Bill:
So, how did you get into it?

Jon:
Actually, I was in the right place at the right time. I received an email about the job opening while at UW, and my present supervisor was also from UW. After a successful interview, I got the job.

Bill:
Describe what you do.

Jon:
What I mainly do is mechanical design. The scientists approach us with either the needs of their instrument, or they need a certain type of data and we design the instrument. Electrical engineers design the circuit board and control software. Mechanical engineers design pressure casings, seals, ballasting and other structural needs. We also work on the geometric design of the instrument platform and try to integrate all the different design needs. With 3-D modeling software we can test and evaluate these designs on a computer. For example, the Remote Access Sampler (RAS) frame was modeled using factors such as its weight, center of gravity and how it will sit on the ocean bottom. We can use the computer software to test its structural strength by applying different weight at the ends or trying to bend it. We can separate the frame into components and do structural analysis. Then we pull it back together and do mechanical drawings. Those are sent to the shop for fabrication. Using the drawings, I work with fabricators, welders and machinists until we come up with the final instrument.

Two bottom pressure recorders (BPR) were deployed this evening at Axial. BPRs are in the two instruments front and right. In the background is the ocean bottom hydrophone (OBH) deployed at the start of the expedition.

Bill:
What's your current project here on the Thompson?

Jon:
I'm currently working on NeMO Net, which is a joint NOAA, University of Washington and Oregon State University project. I designed the RAS, and I'm here to be sure that it is deployed properly. It has 50 bottles to take water samples while actively measuring temperature and pH. It also has an acoustic release so that it can be remotely recovered. After sending an acoustic signal from the Thompson, the RAS drops its anchor and floats to the surface for recovery. We integrate communications with an acoustic modem and a self-leveling mount so that it points up. This enables communication to the buoy and then back to the lab.

Bill:
How much of the information is communicated in real time and what information is stored and must be retrieved later?

Jon:
Bottom pressure and temperature are communicated in near real-time daily at the NeMO Net web site (http://www.pmel.noaa.gov/eoi/nemo/realtime). The fluid from the hydrothermal vents is sucked up from three locations for comparison.

Bill:
What's the most difficult problem that you encountered?

Jon:
Because it does so many things, this particular package is a monster. It's very heavy; weighing about as much as a small sports car. It's hard to move around deck, and moving it can be very dangerous if the ship's deck is also moving. Obviously we have an excellent crew on the Thompson, but it is an issue moving something this big while at sea. A critical design challenge was to make it small enough for deployment.

Sulfide worms (bright orange near top of image) near the top of Hell sulfide structure. A photo/video survey was performed to observe feeding behavior and the territoriality of the worms.

Bill:
Looking into the future, how do you see yourself involved?

Jon:
I see a more complex, multi-noded NeMO Net. There are two sides to the challenge. There's the scientific side, crafting the questions that need answering. Then there's the technological side, designing instruments to answer those questions. Perhaps the future will bring remote controlled devices like the lunar crawler, which can be directed from land to carry out deep-sea sampling. There will be less dependence on ship-dependent devices like ROPOS. The future will be quicker and more mobile, more like a living real time observatory.