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The VENUS engineering team has selected Ramsay Machine Works of Sidney, BC to retrofit the 6-meter-wide buoy for the Buoy Profiling System (BPS). The buoy is destined to be deployed in the Saanich Inlet and will be connected to the VENUS Node. The BPS is an integrated component of the VENUS Phase II development, which will see VENUS to expand from a seafloor cabled network into a geospatial ocean observing system.
More information about VENUS Phase II
On February 15 & 16, the Department of Fisheries and Oceans held the annual meeting to assess the State of the Ocean for 2011. We recently submitted our fourth contribution to this important and broad-reaching document. Included in this report are the three CTD time series from our three Node locations, Saanich Inlet, and Strait of Georgia Central and East, available from our State of the Ocean page. The Saanich Inlet time series is now over 6 years long, and reveals weekly, monthly, annual and inter-annual variations. Of key note for 2011 was the relatively mild spring and slightly cooler summer, which resulted in a prolonged melting of the large coastal snow pack and a prolonged Fraser River freshet, and the capturing of May and June dense water in-flows at the SoG Central site.
VENUS 2011 State of the Ocean Report (PDF)
VENUS State of the Ocean Reports from previous years
VENUS State of the Ocean page
The CODAR station at the Westshore Terminal in Tsawwassen measures surface ocean currents using radio signals reflected off waves in the Strait of Georgia.
A second station, near Vancouver Airport, will be installed in the next month or so, after which it will be possible to resolve north-south and east-west components of the currents. In the meantime, with only a single station operating, it is possible to measure only radial current velocities–that is to say, only the components of ocean currents that are directly towards or directly away from the receiving antenna can be detected.
Interpreting the physical meaning of plots of radial velocities is challenging. An extremely small current-velocity arrow pointing due west, for example, may be evidence of an extremely weak westward current, but it could also correspond to an extremely strong northward current with a very small westward component.
Nevertheless, this animated sequence of radial current vectors from February 1, 2012 gives some tantalizing hints of the current patterns that will be fully resolvable once the second station is up and running.
A plot of estimated tidal heights and current speeds lies below the mapped currents. Current speeds are shown in red, with positive values denoting incoming tide (flowing south to north) and negative values denoting an outgoing tide. Tide heights are shown in blue.
At the time of peak incoming tidal flow, at 04:00 UTC, one would expect to see currents moving northwest, along the Strait. Looking at those CODAR arrows that lie parallel to the Strait’s direction, this is in fact what is seen at 04:00. Similarly, at 22:00, at peak outgoing tidal flow, the CODAR arrows (again, those that are parallel to the Strait’s direction) indicate a flow to the southwest, as one would expect.
The first vessel selected to host a VENUS SeaKeeper 1000 instrument system is BC Ferries’ Queen of Alberni. The system will support the following seawater sensors: temperature, conductivity (salinity), oxygen, chlorophyll and turbidity, and in addition it will be integrated with a comprehensive meteorological sensor suite located on the upper decks of the ferry.
The Queen of Alberni regularly crosses the Strait of Georgia from Duke Point, Nanaimo to the Tsawwassen Terminal in Delta. All the data from this ferry system and future systems will be available on the VENUS online data portal.
In the image: Queen of Alberni in dry dock (Dec 2011).
The first of two High Frequency (HF) Radar Stations was successfully installed on Nov. 24th at the Westshore Coal Terminal in Delta, BC. The station is now monitoring radial surface currents within a 20 km range in the Strait of Georgia. The installation timeline happened to overlap with the onset of a strong winter storm. The engineering team managed to erect the antenna in strong winds, but were able to escape the worst of the storm by 2 hours. Monitoring surface currents in real-time using this technology will bring multiple benefits to a number of organizations, helping them to make important operational decisions. The second station will be installed 20 km to the north in early 2012. Once operational, the radial data from both sites will be combined to generate vector maps of surface currents in a 20 km X 20 km grid between the stations.
Summer has been a busy time for UVic Co-op student Rowan Fox (left). Rowan has proven to be a great asset to the VENUS engineering team during the integration of the SeaKeeper 1000 instrument system destined for BC Ferries’ Queen of Alberni. The image shows Rowan running a test of the Ferry Box system, with VENUS technologist Denis Hedji (center) and Phase II Project Manager Paul Macoun (right) looking on. The test went well!
 CODAR – Coastal Radar
The installation of the first Coastal Radar (CODAR) station at Westshore Terminals, south of Vancouver, is well underway. When complete, in September, radial surface velocity data will be available through the VENUS website. The second CODAR station, located 22 to the north, will be operational in 2012. By combining data from both stations, VENUS will provide surface current maps in the Southern Strait of Georgia every 30 minutes.
BC Ferries Instrumentation
The installation of an instrument system on the M/V Queen of Alberni is also rapidly progressing. In October, during a scheduled maintenance dry dock period, the hull will be fitted with an external pod 2 m below the waterline. A suite of instruments will take standard measurements that will be recorded in a data logger and then transmitted via satellite to the database at UVic. Within minutes, the latest data will be available on the VENUS website. Our longer term plan is to make the data available to ferry passengers, too.
Buoy in Saanich Inlet
The design of the buoy profiling system is nearing completion. Development of the winch system and instrument interfaces has been underway for several months. The expected delivery date for the winch system is November 2011. It will then undergo integration testing before eventually taking its place on the buoy. Surface to seafloor profiling operations will begin in summer 2012 after we link this mid-Inlet system to the VENUS node.
Bluefin AUV (Ocean Technology Lab, UVic)
The Ocean Technology Lab (UVic, Engineering Dept), a long-time partner of VENUS, has made significant progress integrating an instrument suite into their AUV. The OTL team plans testing of the vehicle in August in Saanich Inlet.
VENUS team members assemble a portable transponder in April 2011 at the Roberts Bank coal terminal in Tsawwassen. The transponder was used to map the antenna pattern of the planned “CODAR” (coastal radar) installation in a 1 km circle around the antenna site.
Once installed, the CODAR system will have the ability to measure surface ocean currents almost all the way across to Galiano Island (visible in the background) on the opposite side of Georgia Strait. It may be possible to use BC Ferry vessels, like the one seen in the distance, as passive radar reflectors in order to measure antenna patterns. This will corroborate (but not completely replace) antenna patterns measured using transponders from small, open boats.
During the week of April 12th, the VENUS Engineering team tested several locations for CODAR antennae installation. This week’s Image of the Week shows the radial coverage pattern from one of the proposed sites: Westshore Terminals, site 2.
Ultimately, the VENUS CODAR system will employ two CODAR stations, one at IONA and one at the Westshore Terminals. When both stations are installed (2011), we will obtain and serve our users radial current vector data for the entire region between the two stations located 20 km apart.
For more details on Phase II developments visit: http://venus.uvic.ca/research/venus-phase-ii/
Several projects have begun to take shape as part of the VENUS Phase II.
Our current activities for Saanich Inlet centre on the profiling system. The former CTD Station SI-6, located 4 km south of the VENUS Node, was selected through consultations with users. We have applied for permit to install a fixed buoy there. The engineering group is in the final stage of selecting a supplier for the winching system, and a 7m buoy has been secured from DFO through Crown assets. The buoy will be refurbished and customized to support the winching system, which will be cabled directly to the VENUS Node. We anticipate the Buoy Profiling System (BPS) will be operational in the summer of 2012.
We have also ordered an Environmental Sample Processor (ESP) from Spyglass Bio-security through our collaboration with UBC. The ESP is a water sampling system that performs genetic analysis in situ. This instrument system is slated to be integrated on the profiler instrument cage in 2013.
In the Strait of Georgia, several initiatives are underway. The Central Node has been upgraded and redeployed, now with eight ports which doubles its capacity to support science packages.
The East Node is currently out of the water to get the same upgrades. It will be redeployed in February 2011.
Our Coastal Radar antennae (CODAR Seasonde 25 MHz), which will map surface currents of the southern Strait, have arrived. We plan to erect the antennae in two locations on the Vancouver side of the Strait. Currently, we are still waiting for permits to operate these systems but anticipate one if not both will be operational in the summer of 2011.
Three Seakeeper 1000 systems, the turnkey solution for supporting instruments on BC Ferries, have been ordered, and the anticipated delivery date for this hardware is March 2011. We will endeavour to install one of the systems on a vessel regularly traveling the Tsawwassen to Duke Point route this year. The remaining systems will be installed on the other main routes that regularly cross the Strait in 2012/13.
Stay tuned!
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