ROPOS: The primary investigative tool on our cruise is the ROPOS (Remotely Operated Platform for Ocean Science). It is a ROV (Remote Operated Vehicle) from the Canadian Scientific Submersible Facility that allows for deep dives to the seafloor without the use of a manned submersible. As a result, the vehicle can remain on the bottom for longer periods of time and poses less of a safety hazard. ROPOS is piloted from a control room on the R/V Thomas G. Thompson through an electrical-optical cable. Once near the seafloor, ROPOS has video and still cameras connected to monitors on the research vessel. For operations involving sampling as well as equipment deployment and recovery, ROPOS has robotic arms controlled by an operator on the research vessel using a force feedback system that allows the operator to feel any resistance to the arm's movements. A retractable tray, located on the front of the ROV, can be used to store samples to be carried up to the surface. During this cruise, a new cable laying system will be tested for use in the deployment of the NEPTUNE underwater cable observatory.
ROPOS Magnum Manipulator arm
OBS: An OBS (Ocean Bottom Seismometer) is a sensor that is deployed on the seafloor to measure and record earthquake activity. Each OBS has its own battery pack that allows the device to be left on the ocean bottom to continuously record data for periods of 1 year. While on the seafloor, the OBS records the number of earthquakes and their intensities in a time series. Once the OBS is recovered, the data that it has collected can be downloaded and analyzed by scientists.
OBS internal glass sphere with electronics
CTD: The CTD (Conductivity Temperature Density) is a standard oceanographic tool. It is an electronics package that is lowered from the ship into the water on a conducting cable. The basic functions of the CTD are to measure electrical conductivity (which is related to salinity) and temperature of the water at various depths in the water column. Other parameters can be measured by attaching additional sensors to the CTD, such as a fluorometer to measure chlorophyll concentrations and an oxygen sensor for measuring dissolved oxygen concentrations. Each sensor is capable of providing quick and accurate data back to the ship. The CTD can also carry 24 ten liter bottles. These bottles can be closed when desired to obtain water samples from specific depths in the water. With the data collected by the CTD, scientists can study the physical and chemical characteristics of the ocean.
CTD on rosette with ten liter sample bottles.
NEPTUNE: The NEPTUNE (North East Pacific Time-series Undersea Networked Experiment) array is a large underwater cable observatory being built on the Juan de Fuca plate using electrical optical cable. When completed, the array will allow scientists to gather real time data on the geological, chemical, biological, and physical properties of the seafloor environment while the scientists remain on shore. Video and still shot images from the seafloor will also be available through cameras mounted on the array. In addition to serving as an investigative tool for scientists, NEPTUNE will also allow the general public to view the seafloor through the power of the internet. Two arrays will be completed, one by Canada and one by the United States. Once completed, the NEPTUNE array is expected to remain in use for as long as 20-30 years.