SATURN observation network: the workings and output of a long term biogeochemical observatory in the Columbia River estuary Michael P Wilkin 1, Katie E Rathmell 1, Jo A Goodman 1, Charles Seaton 2, Sarah Riseman 2, Paul J. Turner 2, Albert A Little 3, Joe Needoba 2, Antnio M. Baptista 2 1&2 Center for Coastal Margin Observation and Prediction (CMOP) 1 Oregon Health & Science University (OHSU), MERTS Campus, Astoria, OR 2 OHSU, Portland, OR 3 Clatsop Community College, Astoria, OR SATURN-01: Situated in the North Channel this station is an automated winched profiler, essentially a ships CTD, attached to guide wires on pier 12 of the Astoria-Meglar bridge in 18m of water at chart datum. The profiler oscillates up and down travelling at ~10cm/s, a single profile (up or down) takes 3 to 4 minutes depending on the tide, followed by loitering at the end point until the next 5 minute point is reached when the profiler moves on again. The speed of the profiler is a careful balancing act, move too fast and the sensor cant respond quickly enough to characterize the water column, move too slowly and the environment changes faster than the repeat profiling time. The loitering at the end of the profile allows slower responding instruments to collect data effectively in the surface water and bottom water parts of the water column. The rapidly alternating salt-fresh water caused by the profilers up and down movement serves to keep the package remarkable clean for subsea deployed sensors. However the active mechanical nature of the system means that a weekly service visit is necessary. SATURN-02: SATURN-04: Situated at one of the entrances to Cathlamet Bay, this station is at the end of a 500m long pier at Tongue Pt. The station is a pumped port system similar to SATURN-03. The quieter nature of the station allows a float to be used as the upper intake with the pump moving up and down with the tide. A davit and winch system allows the recovery and service of the float and any associated instrumentation. A second intake is located at the seabed. The station serves as a proving ground for instruments and systems before they move to the more aggressive and dynamic environment at SATURN-03 MV Forerunner: A 50 former trawler owned and operated by Clatsop Community College for seamanship training as part of their USCG Training Ship program. The vessel cruises the estuary 2-3 times per week during term time. She has been outfitted by CMOP with an in hull ADCP, flow-through instrument system and a telemetry link. The instrumentation is switched on as part of the standard ships start up procedures and collects data on every outing regardless who is on board. An oceanographic winch, a heavy lift winch and a crane are also fitted. CMOP conduct regular CTD cruises, with the seamanship students operating the deck equipment, to monitor the performance of SATURN and other stations. Data Access: Wherever possible data is returned to shore via a telemetry system consisting of 900MHz spread spectrum radios and a 2.4GHz SWAP (Ships Wireless Access Protocol) system. Many stations also have local storage; these are downloaded periodically or on recovery and the data combined with the real-time data to fill outages resulting from telemetry issues. All collected data is then made available via a web interface atImages of data for the last 2, 7 and 15 days are available through the station pages. In addition, the Data Explorer interface allows data from multiple sources to be combined and displayed graphically for periods ranging from the entire history of a station to a single day. This system covers all accessible data collected since the observatorys inception. The selected data sets can be freely downloaded and the graphs saved to the users local computer.www.stccmop.org Acknowledgements: This material is based upon work supported in part by the National Science Foundation under cooperative agreement OCE Murdock Foundation (major instrumentation) Oregon Department of Transport (SATURN-01) Point Adams Packing Company (SATURN-03) Tongue Point Job Corps Center (SATURN-04) Quinault Nation (Phoebe & Dione) Submitted to: Columbia River Estuary Workshop 2014, Astoria, OR Quality Assurance: Place an instrument in the water and it will give you a simple reading of that parameter. Leave the instrument in the water and rapidly the quality of that reading will start to degrade as the instrument becomes covered in marine growth. Add additional stations and inter-instrument accuracy starts to show that despite the initial cost and accuracy of the sensors far more work is going to be required to produce a worthwhile data set that has both wide spatially coverage and long duration. Many anti-fouling strategies have been developed, but the usual trade off is how much of the time can the sensor be exposed to the environment compared to it being hidden behind a copper shutter or in an quiet antifouling chamber. The more dynamic the environment, the more often the sensor needs to be exposed; the Columbia Estuary is a very dynamic environment. Quality Control: Quality assurance protocols are in place prior to data collection to maximize the likelihood that the data will be of the highest possible quality. However, the raw data must also be evaluated in order to determine its actual quality. This quality control process is sensor-specific and generally includes: automated thresholds; visual inspection of the data to identify periods of sensor malfunction or suspect data; a review of the data in the context of other SATURN stations, both currently and within a historical context. In addition, corrections may be made for issues such as sensor drift, bias, or other artifacts. Ultimately, the quality controlled data are assigned to one of five final quality levels. This quality determination, along with any corrections made, is detailed in supporting documentation available through metadata and web pages. Quality assurance and quality control protocols are continuously being improved and adapted as more information and results become available. Overview: Observatories in coastal and estuary waters are a compromise with many competing concepts. A commercially developed area with a long history of development and use presents even more challenges. Opportunities for stations are rarely available where the science would like, and those that are available may force data collection methods to vary making uniformity difficult to find. Making stations reliable enough to keep the logistic challenges of maintenance achievable may mean reducing the sampling below the ideal. CORIE started as a physical oceanography observatory around the Columbia Estuary, the Channel, runs right through, but the North channel truncates just east of the Astoria- Megar Bridge. To the side are lateral bays; Baker, Grays, Cathlamet and Youngs. These lateral Bays are fundamental to the ecosystem of the Estuary. The major SATURN described attempt to cover as much of the diversity and variation as possible, the smaller CORIE stations fill in some gaps and outfitted vessels give some indication of what may be happening in between SATURN-03: Situated in the South (navigation) Channel, this station is a pumped port configuration. Water is pumped from 3 levels; near surface, mid-water and seabed. Submersible pumps are located at each level with a temperature sensor (as the temperature of the water may be changed as it passes through the water layers and atmosphere above), hoses lead to instruments housed in the building above water. A series of computer operated selector valves select a level alternating each minute, the remaining levels are simply discharged back to the river SATURN-07: The Estuarys lateral bays seem quiet backwaters, however the tide constantly pumping water in and out, solar heating of the shallows, and even their quiet nature, make these bays fundamental to the ecosystem of the estuary. A buoy has been established in Baker Bay to observe the changing waters in the bay, and a kayak outfitted with a similar set of instruments is paddled around the bay by volunteers on summer weekends, extending the understanding of the variation beyond the single point that the buoy observes. Baker Bay is broad and shallow, finding a spot that allows the buoy s instruments to observe the passing water while not stirring up the sediments with a mooring chain, limits where the buoy can be placed. Instruments: CT, DO, CDOM, PE, Multi-exciter (includes chla & turbidity) Phoebe and Dione: Slocum Ocean Gliders propelled by buoyancy engines, first Phoebe (sadly lost to the ocean) and now Dione survey the waters off the Washington Coast. The glider is deployed for a month a time covering about 500km in a horizontal zigzag pattern from 10 to 30nm offshore, and a vertical see-saw from the surface down to 200m in depth before returning to the point of deployment for recovery Instruments: C, T, depth, DO, chla, turbidity, CDOM Station Locations: SATURN stations (01, 02, 03, 04 & 07) CORIE stations: ogi01: offshore buoy jetta: Jetty A sandi: East Sand Island dsdma: Desdemona Sands light ncbn1: North Channel bottom node tansy: Tansy Point am169: Astoria-Meglar Bridge pier 169 grays: Grays Point cbnc3: Cathlamet Bay North Channel (light 3) eliot: Elliot Point woody: Woody Island Quality assurance starts with testing instruments in the workshop before and after deployment and, where possible, recovering instruments periodically for mid-deployment tests. Instruments are recovered in groups of the same parameter to allow as much cross comparison as possible. For the pumped stations (SATURN-03 & 04) DI water is pumped through the flow cells each week to check the drift of the instruments zero offset. Alternate weeks MV Forerunner is utilized to perform CTD casts at as many stations as practical, to provide cross comparison between stations, as well as between instruments. Finally, water samples are collected for laboratory analysis. Essentially, monitoring the instruments is as important as monitoring the Estuary if a good data set is to be produced. Development is always ongoing.. The observation network is very responsive to changing requirements and new technologies. However, in order to produce long term time series a certain inertia is required, if we start something we like to keep it going for a prolonged period. In the Estuary it is frequently a case of finding stations of opportunity rather than being able to develop a new station exactly where we would like it. Lateral Bays are increasing an area of interest, to accommodate this a new SATURN station is planned for the center of the New Youngs Bay Bridge. MV Forerunner represents an excellent platform for data collection as she regularly cruises the Estuary year round in her primary task of seamanship training. Further instruments are to be added to her flow-through system that is active whenever she is at sea. For the shallow waters of the lateral bays a kayak has been outfitted with an instrumentation suite. This suite is being reconfigured to suit CMOPs inflatable RHIB so that this instrument package can be used more regularly and in different bays than was possible with the volunteer propelled kayak. SATURN-04 & SATURN-03 are available for test deployment of new or novel instrumentation. using bypass valves. The water flows through the series of sensor flow cells before reaching an air- break at the highest point, and then being discharged back into the river. This, push from below always uphill to the air break, ensures a positive pressure is maintained throughout minimizing the formation of air bubbles. The pumps run continuously keeping the water at the valves current with the water at the intake, only first 30 seconds of the sampling period is required Observatory developed over the years to become the SATURN biogeochemical observation network with NSF funding from CMOP and Murdock Foundation funding for major novel instrumentation. Ocean conditions are observed to the north with ocean gliders and to the south with observation buoys. There are two concepts to the ocean observations, how the ocean effects the estuary and how the estuary effects the ocean. River conditions are monitored up stream by stations at Beaver Army Terminal, Bonneville Dam, and Willamette River (these are not described here). In between are the Estuary stations observing the interaction between the River and Ocean. Here though there are still very different environments to observe. There are two main river channels, the South shipping MV Forerunner is also used to deploy and recover oceanographic buoys in the Estuary and in Coastal waters, as well as the remote seabed mounted Acoustic Profiler frames at SATURN-01, 03 and 04. Instruments: C, T, DO, Chla, turbidity, CDOM, PE, nitrate, quantum yield; Remote seabed frame ADP, CT A coastal ocean observing buoy, stationed about 8km south of the tip of the South Jetty in 40m of water. Above the water is a meteorological station, an AIS beacon and solar panels for power. Immediately underneath and mounted to the frame of the buoy are sensors for CT, CDOM, DO, nitrate and a Multi- Exciter that incorporates chla and turbidity. Also mounted to the buoy is a down looking acoustic velocity profiler that can detect currents also to the seabed in 50cm bins. Further down the mooring string are a series of CT sensors, until finally a combined CT and DO sensors as close to the seabed as the mooring configuration will allow. The mooring is generally deployed in the spring and recovered in the fall. Instruments: CT, DO, chla, turbidity, pH, nitrate, pCO2, CDOM; Remote seabed frame: ADP Outside term time, MV Forerunner is used to collect a variety of Oceanographic data and samples in the Estuary and Coastal Waters CMOPs data policy ensures that all collected Oceanographic and Environmental data is freely and publicly available at the earliest opportunity. Selected variables are also accessible through NANOOS (the regional association of ocean observing systems) and through NDBC (the national data buoy center). to flush the flow cells before valid data is collected from the instruments. The station is also equipped with a remote seabed mounted acoustic velocity profiler. Once logistics have been worked out, usually at SATURN-04, the station can play host to occasional or experimental instruments; this has included an ESP, APNA, SeaFlow & CycleP.