Teacher Logbook - NOAA Ship Ron Brown

RAS at Cloud vent, marker-N6, where it will be deployed for NeMO Net the next year. After the RAS was placed at Cloud vent on dive R630, the NeMO Net buoy was deployed from the Ron Brown.

Jeff Goodrich's Sealog:
Axial Volcano - 1998 lava flow
July 28, 2001

The scientists are gathering mounds of data about the dynamic nature of Axial Volcano and it's hydrothermal vents. However, for a deeper understanding of this complex tectonic system, snapshot science really doesn't cut it. Continual monitoring or monitoring during eruptive events is ideal. This process has already been started. In 1998 a rumbleometer, a device that measures vertical displacement and temperature, detected inflation and deflation of the volcano during the eruption. MTR's and HOBO's (temperature recorders) monitor the
temperature of diffuse and hot vents on an ongoing basis. Vent chemistry is the piece of the puzzle that, until now, has only been monitored during NeMO cruises. With the RAS (Remote Access Sampler) and the NeMO Net buoy, real-time chemical data will be gathered when the scientists feel it's needed. Scientists deployed the RAS at Cloud vent last night and spent a lot of time checking and double checking how and where they wanted it positioned, its alignment, and if it was able to communicate. Today, the second part of the NeMO Net system was deployed. The NeMO Net buoy will receive messages acoustically from the RAS and send the message, via the LEO (Low Earth Orbiting) satellite system, to the Pacific Marine Environmental Laboratory in Seattle. It allows two-way communication for desktop-to-seafloor chemistry. Chemical oceanographer Dave Butterfield can specify when he wants a sample taken and in which of the 48 bottles on the RAS he wants to store it. A default mechanism triggers the RAS to sample one bottle per week and a chemical scan of temperature, pH, and H2S (hydrogen sulfide) every three days. The RAS has taken the chemistry lab to the ocean floor.

The NeMO Net buoy is tethered to the seafloor, held in place with a railroad-car wheel. It restricts diving within 2 km of its vicinity due to a risk of tangling ROPOS in it's tether so scientists were busy last night finishing up work around the Cloud vent area. Our few remaining dives are limited to other areas in the caldera. The NeMO Net/RAS is another step toward real-time monitoring of the vents on a continual basis. Perhaps in the future the sampler won't be stationary. An autonomous underwater vehicle (AUV), stored in an underwater garage, will be controlled from scientists on shore. It will move from vent to vent, sampling and uploading data to the web for all to see.