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The mooring cable is used as the transmission medium, eliminating the need to cable connect each sensor. The IMM transmits sensor data to the surface by applying a signal to the internal winding of an ?inductive cable coupler? (ICC). This induces a signal in the single-turn secondary winding formed by the mooring cable passing through the ICC. The SIM at the surface receives the signal from each sensor using con g-ured system ID numbers (01 -10). The buoy controller and all systems integration were completed by AMBIDADOS in Rio. The data logger is a Campbell Scienti c CR1000 with daily data telemetry undertaken by an onboard INMARSAT transmitter, a Skywave IsatData Pro with and integrated GPS system for buoy positioning and watch circle monitoring. A second, positioning device (GlobalStar Tracker) is also in- stalled on the tower shelf for back-up buoy position monitor- ing should the Skywave system go down. The complete sys- tem is powered by an onboard battery pack that supplies the necessary power for a 12-month deployment. The mooring chosen for the ATLAS-B application is a semi- taut design where the length of the mooring is slightly longer than the site depth (scope of: 1.05). Not quite taut (0.985) and not slack. This approach allows more forgiveness in nylon elongation (stretch) while keeping the in-water sensors at or close to the desired measurement location within the water column. 700m of 3/8? jacketed wire rope (3x19), a standard in ATLAS and other mooring applications and a necessary com- ponent for the induction process, is used in the upper mooring. The wire rope also helps protect against shark and sh bite in the surface region of the mooring. At the buoy to mooring bridge (mooring connection point) an ?inductive jumper? (J. Kinder, J. Cappellini) is used for the transfer of all sub-surface data to the buoy controller. This allows for the ICC to be buoy mounted on the bridle vs. mounting on the mooring, a more robust option for a long-term deployment. The upper swedge tting is tapped for the bare end of the jumper cable to be inserted and secured with a series of hex-screws and epoxy then the entire termination is made water proof using rubber, tape and a two-part epoxy coating. The buoy end of the jumper is bolted to the bridle transferring the salt water ground from the mooring to the buoy. From 700m down to the acoustic releases, mounted just above the anchor is 18mm diameter nylon ber rope married together with shackles and sling links in 500m sections. Glass ball otation is distributed throughout the mooring to keep tension on the system and is used as backup otation for system recovery should the buoy break away from the mooring. A shot of 20mm nylon is used between the acoustic releases and railroad wheel anchor along with a short section of chain.DeploymentOnce all systems components were built and tested in Rio, ATLAS-B was sent to the small sea-side village of Ubatuba, Sao Paulo, about a four-hour drive south of Rio de Janeiro. IOSUP has a satellite campus here with a small research ves- sel available to faculty and students for offshore projects. ATLAS-B was moored a short distance from the pier for a ?wet-test? prior to the trip offshore to the Atlantic. Research Vessel Alpha Crucis (formerly RV Moana Wave of the Univ. of Hawaii now owned and operated by the IOUSP) arrived at Ubatuba to load the buoy, systems components and the science team. On April 22, after a short few days transit, ATLAS-B was deployed at position 28º 30?S / 44º 00?W at a depth of 3,700m with 100% data transmission. Times series of daily data are being received and processed and are publically avail- able at ftp://ftp.io.usp.br/labmon/ATLAS-B. Quality control and analysis are conducted to transfer the data onto the GTS network. Buoy data are compared to the National Center for Environmental Prediction (NCEP) Reanalysis data set (data that incorporates in-situ measurements with numerical mod-els and is continuously updated representing the Earth?s at- mosphere). All data compares well with exception of some normal aches and pains of a prototype buoy system design and a rst deployment. ConclusionThe development of a Brazilian alternative for the ATLAS buoy and mooring system can be considered a great success. This was the rst time a complete design, assembly and de- ployment of such a deep water monitoring platform was car- ried out exclusively in Brazil. The present site will be main- tained as a pilot project for a few years and once the ATLAS-B design proves itself capable and scienti cally valuable it will be transformed into a sustained observing component of the Brazilian climate research program. A second ATLAS-B sys- tem is being constructed now, to be built entirely in Brazil, including the buoy. This system will replace the prototype upon recovery in early 2014. Acknowledgement Corresponding authors: Carlos Franca, Luiz Nonnato and Francisco Vicentini, IOUSP. This research activity has been conducted with support from the Brazilian National Institute of Science and Technology for Climate Change (INCT-MC), funded by the Brazilian National Council for Scienti c and Technological Development (CNPq) and the Sao Paulo State Foundation for Scienti c Research (FAPESP). The ATLAS-B oceanographic cruises are conducted on board the Research Vessel Alpha Crucis, purchased with funds from FAPESP. Figure 1 courtesy of: P. Brandt, GEOMAR, Helmholtz Cen- tre for Ocean Research Kiel, Germany, http://www.geomar. de. PIRATA information was pulled from: http://www.pmel. noaa.gov/pirata/ maintained by NOAA, PMEL and the Bul- letin of the American Meteorological Societies (BAMS), Au- gust, 2008 edition (Bourles et. al). We acknowledge the hard work by all involved to get ATLAS-B to sea and successfully transmitting data to shore. Further pictorial and video of the ATLAS-B cruise can be seen at: www.rdsea.com Ocean Observation September 201350 MTRMTR #7 (50-65).indd 50MTR #7 (50-65).indd 508/22/2013 11:26:09 AM8/22/2013 11:26:09 AM
