Posts Tagged ‘Coastal Endurance Array’
Expanding Reach of OOI Data

OOI shares data with partner repositories and institutions that host similar data but have different user bases. These partnerships expand the data available for forecasting models, help provide insight into current ocean conditions, and serve as important resources for many ranging from fishers and other maritime users to land-based researchers and students.
With the exception of the Station Papa Array, the OOI Coastal and Global Arrays maintain surface buoys. Instruments deployed on these buoys measure meteorological variables such as air temperature, barometric pressure, northward and eastward wind velocities, precipitation, solar radiation, and surface water properties of sea surface temperature and salinity. Other instruments on the moorings collect wave data, such as significant wave height, period, and direction. These data are then consumed by national and regional networks to improve accuracy of weather forecasting models.
The Regional Cabled Array (RCA) consists of fiber-optic cables off the Oregon coast that provide power, bandwidth, and communication to seafloor instrumentation and moorings with instrumented profiling capabilities. A diverse array of geophysical, chemical, and biological sensors, a high-definition camera, and digital still cameras on the seafloor and mooring platforms, provide real-time information on processes operating on and below the seafloor and throughout the water column, including recording of seafloor eruptions, methane plume emissions and climate change. These data are available for community use. Since 2015, the RCA has fed data into Incorporated Research Institutions for Seismology (IRIS), the primary source for data related to earthquakes and other seismic activity. In addition, data including zooplankton sonar data, are being utilized within the Pangeo ecosystem for community visualization and access and pressure data are incorporated into NOAA’s operational tsunami forecasting system.
Helping Improve Models and Forecasting
One of the recipients of OOI data is the National Data Buoy Center (NDBC), part of the National Oceanic and Atmospheric Administration’s (NOAA) National Weather Service. NDBC maintains a data repository and website, offering a range of standardized real-time and near real-time meteorological data. Data such as wind speed and direction, air and surface water temperature, and wave height and direction are made available to the broader oceanographic and meteorological community.
“Many researchers go to NDBC for their data, “said Craig Risien, a research associate with OOI’s Endurance Array and Cyberinfrastructure Teams, who helps researchers gain access to and use OOI data. “NBDC is a huge repository of data and it’s easy to access. So there’s a low barrier for researchers and students who are looking for information about wind speed, water temperature and a slew of other data. OOI contributing to this national repository significantly increases its data reach, allowing OOI data to be used by as many people as possible. “
OOI sea surface temperature data also make their way into the operational Global Real-Time Ocean Forecast System (RTOFS) at the National Centers for Environmental Prediction (NCEP), another part of NOAA’s National Weather Service. RTOFS ingests sea surface temperature and salinity data from all available buoys into the Global Telecommunications System (GTS). OOI glider data also are pushed in near real-time to the US Integrated Ocean Observing System Glider Data Assembly Center (DAC). From there, the data goes to the GTS where it can be used by the operational modeling centers such as NCEP and the European Centre for Medium-Range Weather Forecasts.
The GTS is like a giant vacuum sucking up near real-time observations from all sorts of different platforms deployed all over the world. On a typical day, the GTS ingests more than 7,600 data points from fixed buoys alone. As a result of this vast input, researchers can go to the GTS, pull available data, and assimilate that information into any model to improve its prediction accuracy.
Advancing Forecasting of Submarine Eruptions
As the first U.S. ocean observatory to span a tectonic plate, RCA’s data are an invaluable contributor to IRIS’s collection. Since 2015, the user community has downloaded >20 Terabytes of RCA seismometer data from the IRIS repository. Fourteen different sampling locations include key sites at Axial Seamount on the Juan de Fuca mid-ocean ridge spreading center, near the toe of the Cascadia Margin and Southern Hydrate Ridge. RCA data are catalogued and available on the IRIS site, using the identifier “OO.”
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“RCA is a critical community resource for seismic data. Axial Seamount, for example, which erupted in 1998, April 2011, was the site of more than 8,000 earthquakes over a 24-hour period April 24, 2015 marking the start of large eruption,” explained Deb Kelley, PI of the RCA. “Being able to witness and measure seismic activity in real time is providing scientists with invaluable insights into eruption process, which along with co-registered pressure measurements is making forecasting possible of when the next eruption may occur. We are pleased to share data from this volcanically and hydrothermally active seamount so researchers the world over can use it to better understand processes happening at mid ocean ridges and advance forecasting capabilities for the first time of when a submarine eruption may occur.”
Providing Data with Regional Implications
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OOI also provides data to regional ocean observing partners. Data from two Endurance Array buoys (46099 and 46100), for example, are fed into a four-dimensional U.S. West Coast Operational Forecast System (WCOFS), which serves the maritime user community. WCOFS generates water level, current, temperature and salinity nowcast and forecast fields four times per day. The Coastal Pioneer Array is within the future Northeastern Coast Operational Forecast System (NECOFS). Once operational, Pioneer’s observations will potentially be used for WCOFS data assimilation scenario experiments.
Coastal Endurance Array data are shared with the Northwest Association of Networked Ocean Observing Systems (NANOOS), which is part of IOOS, and the Global Ocean Acidification Observing Network (GOA-ON). Endurance data are ingested by the NANOOS Visualization System, which provides easy access to observations, forecasts, and data visualizations. Likewise, for GOA-ON, the Endurance Array provides observations useful for measuring ocean acidification.
Data from three of the Pioneer Array buoys also are part of the Mariners’ Dashboard, a new ocean information interface at the Northeastern Regional Association of Coastal Ocean Observing Systems (NERACOOS). Visitors can use the Dashboard to explore the latest conditions and forecasts from the Pioneer Inshore (44075), Central (44076), and Offshore (44077) mooring platforms, in addition to 30+ other observing platforms throughout the Northeast.
“We are working hard to distribute the OOI data widely through engagement with multiple partners, which together are helping inform science, improve weather and climate forecasts, and increase understanding of the ocean,” added Al Plueddemann, PI of the Coastal and Global Scale Nodes, which include the Pioneer, Station Papa, and Irminger Sea Arrays.
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Bottom Boundary Layer O2 Fluxes During Winter on the Oregon Shelf
Adapted and condensed by OOI from Reimers et al., 2022, doi:/10.1029/2020JC016828.
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The oceanic bottom boundary layer (BBL) is the portion of the water column close to the seafloor where water motions and properties are influenced significantly by the seabed. This study (Reimers & Fogaren, 2021) reported in the Journal of Geophysical Research examines conditions in the BBL in winter on the Oregon shelf. Dynamic rates of sediment oxygen consumption (explicitly oxygen fluxes) are derived from high-frequency, near-seafloor measurements made at water depths of 30 and 80 meters. The strong back-and-forth motions of waves, which in winter form sand ripples, pump oxygen into surface sediments, and contribute to the generation of turbulence in the BBL, were found to have primed the seabed for higher oxygen uptake rates than observed previously in summer.
Since oxygen is used primarily in biological reactions that also consume organic matter, the winter rates of oxygen utilization indicate that sources of organic matter are retained in, or introduced to, the BBL throughout the year. These findings counter former descriptions of this ecosystem as one where organic matter is largely transported off the shelf during winter. This new understanding highlights the importance of adding variable rates of local seafloor oxygen consumption and organic carbon retention, with circulation and stratification conditions, into model predictions of the seasonal cycle of oxygen.
Supporting observations, which give environmental context for the benthic eddy covariance (EC) oxygen flux measurements, include data from instruments contained in OOI’s Endurance Array Benthic Experiment Package and Shelf Surface Moorings. Specifically, velocity profile time-series are drawn from records of a 300-kHz Velocity Profiler (Teledyne RDI-Workhorse Monitor), near-seabed water properties from CTD (SBE 16plusV2) and oxygen (Aanderaa-Optode 4831) sensors, winds from the surface buoy’s bulk meteorological package, and surface-wave data products from a directional wave sensor (AXYS Technologies) (see e.g., Fig 1 above).
Reimers, C. E., & Fogaren, K. E. (2021). Bottom boundary layer oxygen fluxes during winter on the Oregon shelf. Journal of Geophysical Research: Oceans, 126, e2020JC016828. https://doi.org/10.1029/2020JC016828
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Mission Accomplished: Endurance 14 Cruise Meets All Objectives
After a 15-day expedition, the Endurance Array Team returned to port aboard the R/V Sikuliaq on 7 April having successfully completed the 14th turn of the Endurance Array. The team recovered and deployed seven surface moorings and completed sampling at all recovery/deployment sites. They also deployed and recovered gliders and surface profilers.
Because of the size and weight of the moorings and other equipment, the trip was conducted in two legs. The first leg was primarily off Washington and the second off Oregon. Between legs, the R/V Sikuliaq returned to Newport, Oregon to offload recovered equipment from the Washington Line and load new equipment for the Oregon Line.
The weather was rough when the R/V Sikuliaq first set off from Newport on 24 March. On the first night out, they saw 19-foot waves and 35-knot winds. The team worked around the weather on the first leg to deploy three moorings and recover four. They also recovered and deployed gliders.
The second leg of the journey brought with it much better weather, which eased the recoveries, deployments, sampling, and other activities. During this leg, the team worked mostly off Oregon. The team deployed four moorings and three profilers and recovered three moorings, three gliders, and a profiler.
Each OOI deployment brings some technical improvement. On this deployment, the Endurance moorings are outfitted with redesigned solar panels on the buoy decks. These panels will deliver more power and be more resilient to wear and tear caused by sea lions who often find the buoys an inviting place to lounge. The redesign was implemented by OOI’s Coastal and Global Scale Nodes team at Woods Hole Oceanographic Institution.
This trip also marked the Endurance Array’s team first use of a OOI’s ROV (remotely operated vehicle). The ROV was used at the Oregon shelf site to recover a coastal surface piercing profiler and its anchor. Throughout the process, the R/V Sikuliaq maneuvered skillfully to place the ship over the target. Mooring lead Alex Wick piloted the ROV through strong currents and limited visibility. It took four dives, but the profiler and its anchor were recovered. On the third dive, the ROV was used to cut the winch line so the team could recover the profiler, and the anchor was recovered on the fourth and final dive.
The Endurance team also collected CTD samples and biofouling samples to share with researchers at the Smithsonian Institute and Oklahoma State University. The R/V Sikuliaq returned to Newport on 7 April with the recovered equipment, which will undergo refurbishment for the next turn of the Endurance Array in September.
“Since 2017, we’ve sailed on the R/V Sikuliaq for six out of nine cruises,” said Ed Dever, the Chief Scientist of Endurance 14. “It’s a match that works well. From ship handling and on-deck assistance to mobilization of underway science sensors, lifting gear, engineering, accommodations, and food, we are deeply appreciative of the Sikuliaq’s captain, crew, and the ship herself.”
Read MoreA Bountiful Sea of Data: Making Echosounder Data More Useful
[media-caption path="https://oceanobservatories.org/wp-content/uploads/2021/03/Screen-Shot-2021-03-30-at-5.51.41-PM.png" link="#"]Researchers used echosounder data from the Oregon Offshore site of the Coastal Endurance Array to develop a new methodology that makes it easier to extract dominant patterns and trends.[/media-caption]The ocean is like a underwater cocktail party. Imagine, as a researcher, trying to follow a story someone is telling while other loud conversations are in the background of a recording. This phenomenon, known as the “Cocktail Party Problem,” has been studied since the 1950s (Cherry, 1953; McDermott, 2009). Oceanographers face this challenge in sorting through ocean acoustics data, with its mixture of echoes from acoustic signals sent out to probe the ocean.
Oceanographer Wu-Jung Lee and data scientist Valentina Staneva, at the University of Washington, teamed up to tackle the challenge in a multidisciplinary approach to analyze the vast amounts of data generated by echosounders on Ocean Observatories Initiative (OOI) arrays. Their findings were published in The Journal of the Acoustical Society of America, where they proposed a new methodology that uses machine learning to parse out noisy outliers from rich echosounder datasets and to summarize large volumes of data in a compact and efficient way.
This new methodology will help researchers use data from long time series and extract dominant patterns and trends in sonar echoes to allow for better interpretation of what is happening in the water column.
The ocean is highly dynamic and complex at the Oregon Offshore site of the OOI Coastal Endurance Array, where echosounder data from a cabled sonar were used in this paper. At this site, zooplankton migrate on a diurnal basis from a few hundred meters to the surface, wind-stress curl and offshore eddies interact with the coastal circulation, and a subsurface undercurrent moves poleward. The echosounder data offer opportunities to better understand the animals’ response to immediate environmental conditions and long-term trends. During the total eclipse of the Sun in August 2017, for example, echosounders captured the zooplankton’s reaction to the suddenly dimmed sunlight by moving upwards as if it was dusk time for them to swim toward the surface to feed (Barth et al, 2018).
Open access of echosounder datasets from the OOI arrays offers researchers the potential to study trends that occur over extended stretches of time or space. But commonly these rich datasets are underused because they require significant processing to parse out what is important from what is not.
Echosounders work by sending out pulses of sound waves that bounce off objects. Based on how long it takes for the reflected echo to come back to the sensor, researchers can determine the distance of the object. That data can be visualized as an echogram, an image similar to an ultrasound image of an unborn baby.
But unlike an ultrasound of a baby, when an undersea acoustic sensor records a signal, it may be a combination of signals from different sources. For example, the signal might be echoes bouncing off zooplankton or schools of fish.
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“When the scatterers are of different size, they will reflect the sound at different frequencies with different strengths,” said Lee. “So, by looking at how strong an echo is at different frequencies, you will get an idea of the range of sizes that you are seeing in your echogram.”
Current echogram analysis commonly requires human judgement and physics-based models to separate the sources and obtain useful summary statistics. But for large volumes of data that span months or even years, that analysis can be too much for a person or small group of researchers to handle. Lee and Staneva’s new methodology utilizes machine learning algorithms to do this inspection automatically.
“Instead of having millions of pixels that you don’t know how to interpret, machine learning reduces the dataset to a few patterns that are easier to analyze,” said Staneva.
Machine learning ensures that the analysis will be data-driven and standardized, thus reducing the human bias and replicability challenges inherently present in manual approaches.
“That’s the really powerful part of this type of methodology,” said Lee. “To be able to go from the data-driven direction and say, what can we learn from this dataset if we do not know what may have happened in a particular location or time period.”
Lee and Staneva hope that by making the echosounder data and analytical methods open access, it will improve the democratization of data and make it more usable for everybody, even those who do not live by the ocean.
In the future, they plan to continue working together and use their new methodology to analyze the over 1000 days of echosounder data from the OOI Endurance Coastal and Regional Cabled Array region.
References
Lee, W-J and Staneva, V (2021).Compact representation of temporal processes in echosounder time series via matrix decomposition. Special Issue on Machine Learning in Acoustics. The Journal of the Acoustical Society of America.
Barth JA, Fram JP, et al. (2018). Warm Blobs, Low-Oxygen Events, and an Eclipse: The Ocean Observatories Initiative Endurance Array Captures Them All.Oceanography, Vol 31.
McDermott, J (2009). The Cocktail Party Problem.Current Biology, Vol 19, Issue 22.
Cherry EC (1953). Some Experiments on the Recognition of Speech, with One and Two Ears.The Journal of the Acoustical Society of America. Vol. 25, No.5.
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Spring Expeditions: Keeping OOI Arrays Fully Operational
OOI teams were in the water on opposite coasts in late March to service the Pioneer and Endurance Arrays. The teams will “turn” the moorings (recover old and deploy new) to keep the arrays continually collecting and reporting data back to shore. This is the 14th turn of the Endurance Array; the 16th for the Pioneer Array.
The Endurance 14 Team set sail from Newport Oregon aboard the R/V Sikuliaq on 24 March for a 15-day expedition. The Pioneer 16 Team departed from Woods Hole, MA, a few days later on 29 March aboard the R/V Armstrong for a 21-day mission. Both expeditions will require two legs because of the need to transport a huge amount of equipment. The equipment for the Pioneer Array weighs more than 129 tons. The Endurance equipment tops the scale at 95 tons.
Departures for both teams occurred after arranging for reduced occupancy on site and social distancing during preparation, followed by 14 days of quarantine to meet COVID-19 restrictions. And while onboard, COVID has necessitated other changes ranging from smaller science parties to scheduled meal times to allow for social distancing.
“It is very impressive that the OOI team has been able to continue to service these arrays in spite of the challenges presented by COVID,” said Al Plueddemann, Chief Scientist of the Pioneer 16 Expedition. “The ocean is a tough environment in which to keep equipment operational, even in normal times. This year, in particular, has required both our shore-based staff and those onboard to be adaptable, flexible, and innovative to get the job done.”
[media-caption path="https://oceanobservatories.org/wp-content/uploads/2021/03/burnin_Travis.jpg" link="#"]The full cycle of preparation for an OOI mooring service cruise takes many months. The “burn-in” period for Pioneer-16, during which equipment is assembled and tested, began in January 2021 with snow on the ground outside of the LOSOS building on the WHOI campus. Credit:Rebecca Travis © WHOI.[/media-caption]In addition to the mooring and deployment recoveries, both teams are deploying and recovering gliders that collect additional data within the water column and the area between the moorings. They also are conducting CTD casts and water sampling at the mooring sites, and doing meteorological comparisons between ship and buoys. The Pioneer Team will be operating autonomous underwater vehicles (AUVs), while the Endurance Team will have its inaugural use of OOI’s own remotely operated vehicle (ROV) to recover anchors at the Oregon shelf site.
“In normal times, we would invite external students and scientists along to conduct ancillary experiments on the cruise,” said Edward Dever, Chief Scientist for Endurance 14. “But given the limited science party allowed onboard due to COVID-19, the OOI team will be conducting some of this additional work to ensure the continuity of these experiments.”
For Endurance 14, this work includes collection of organisms that grow on panels attached to Endurance buoys for invasive species research, collection of settling organisms on devices attached to Multi-Function Nodes, which power near bottom data instruments, and test deployments of tagged fish acoustic monitors on near surface instrument frames on three moorings.
Likewise, the Pioneer 16 Team is helping ensure ongoing science investigations installing and operating unattended underway sampling for the Northeast U.S. Shelf Long-Term Ecological Research (LTER) project and conducting CTD casts at LTER sites during the cruise. They will also conduct communication tests at the Offshore mooring site in support of the Keck-funded 3-D Acoustic Telescope project.
Science teams of 9-10 people on each cruise are sharing the multitude of tasks needed for the moored array service.
[media-caption path="https://oceanobservatories.org/wp-content/uploads//2021/03/Screen-Shot-2021-04-01-at-9.19.20-AM.png" link="#"]OOI’s remotely operated vehicle will be used for the first-time during Endurance 14. Credit: Seaview Systems.[/media-caption]
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Endurance Oregon Shelf Data Provides Insights into Bottom Boundary Layer Oxygen Fluxes
Adapted and condensed by OOI from Reimers et al., 2021, doi:/10.1029/2020JC016828
In February 2021 JGR Oceans article, Clare E. Reimers (Oregon State University) and Kristen Fogaren (Boston College) used data from the Endurance Array Oregon Shelf to advance understanding of how the benthic boundary layer on the Oregon Shelf in winter depends on surface-wave mixing and interactions with the seafloor.
The oceanic bottom boundary layer (BBL) is the portion of the water column close to the seafloor where water motions and properties are influenced significantly by the seabed. This study examines conditions in the BBL in winter on the Oregon shelf. Dynamic rates of sediment oxygen consumption (explicitly oxygen fluxes) are derived from high-frequency, near-seafloor measurements made at water depths of 30 and 80 m. The strong back-and-forth motions of waves, which in winter form sand ripples, pump oxygen into surface sediments, and contribute to the generation of turbulence in the BBL, were found to have primed the seabed for higher oxygen uptake rates than observed previously, in summer. Since oxygen is used primarily in biological reactions that also consume organic matter, the winter rates of oxygen utilization indicate that sources of organic matter are retained in, or introduced to, the BBL throughout the year. These findings counter former descriptions of this ecosystem as one where organic matter is largely transported off the shelf during winter. This new understanding highlights the importance of adding variable rates of local seafloor oxygen consumption and organic carbon retention, with circulation and stratification conditions, into model predictions of the seasonal cycle of oxygen.
The rest of the article can be accessed here.
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Shade and Poop at Sea: Increasing Solar Panel Efficiency
Sea lions intermittently visit the Coastal Endurance Array moorings off the coast of Oregon, where they lounge, bask in the sun, and “do their business.” These visits create two problems for the optimum functioning of the instrumented arrays. Because sea lions are heavy, some weighing up to 2,500 pounds, the solar panels upon which they rest need to be strong enough to bear this weight. And, excrement left behind by these itinerant visitors smears and shades the solar panels, making less power available for the ocean observing instrument attached to the arrays.
This intermittent excrement-related shading compounds an existing shading problem caused by the perpetual movement of the moorings. The halos at the top of the moorings cast shadows over the panels below, resulting in a significant power loss. If ten percent of a solar panel is covered in shadow, for example, its output can drop by as much as 70 percent. When sea lions take refuge on the solar panels this loss is exacerbated. Their excrement, at times, can cover up to 30 percent of the panels, virtually wiping out the power generating capability of the panels. Luckily, this coverage results in only a temporary power shortage as wind and seawater ultimately wash away the remains of these visits.
OOI Engineers John Reine and Marshall Swartz of OOI’s Engineering Team put their heads together to tackle these problems. They first addressed the shading issue.
“These moorings are never still,” explained John Reine, Senior Engineer and lead of OOI’s Electrical Refurbishment Team. “In response to wave and wind-driven motion, the masts are always going back and forth, about three times per minute, casting shadows as they move. So this constant movement of shade, no shade, shade, no shade, produces a sort of alternating current from the panels. I went to Marshall and asked how do we fix this?” (John Reine explains the problems and fixes in the video below).
[embed]https://youtu.be/1d6QQJfHqik[/embed]Solar panels are made up of lots of little solar cells, normally connected to each other so the power flows seamlessly from cell to cell. The Engineering Team recognized that by modifying the panel’s internal circuitry, it could easily harvest more of the available light. They proposed a solution to triple the number of bypass diodes, switches that would ignore shaded cells and move the power to the next operational cell in this field of cells. The manufacturer built a prototype based on an high efficiency cell design, inserting additional diodes, and tested the upgraded array. Tests at the manufacturer’s verification facility and at WHOI showed the modified design exceeded expectations.
Timing was opportune. The original solar panels had exceeded their design lifetime and needed to be replaced, but were no longer in production. The team seized on this opportunity to seek out panels incorporating more efficient cells, wired into a circuit proven to minimize shading energy losses, while also bearing the weight of the itinerant visitors.
The task fell to Swartz to find a solar manufacturer able to incorporate the bypass diodes into the panel design. He worked under the proviso that OOI prefers to buy things off the shelf so as to make repair and replacement easy, affordable, and virtually seamless, when needed.
“Such off-the-shelf solutions have worked out well for us,” said Swartz. “As it turned out, we found a supplier, SBM Solar, in North Carolina that does a lot of work with the military, including high-efficiency solar panels. Working with the president and chief engineer of the company, who was very willing to help us customize a product, we came up with a design having a string of 36 cells in the panel. We specified circuitry with bypass diodes so that when any group of four cells gets shaded, they are bypassed and the rest of the cells in the panel can continue to provide unrestricted power to the buoy.
“Just by making this small change, we significantly improved the total energy harvest in a simulated condition by 50 percent, “ Swartz added. What this means in practical terms is that the solar panels can now harvest useful power from almost any light condition –whether it is the reflected light off the surface of the water, low incidence light at sunset, and light that is filtered through the clouds during an early gray day.
Jokingly, he added, “ These panels basically follow the principle of ‘whenever I have the opportunity to make electricity, I’m going to do it’.”
The new panels also passed the weight-bearing problem for the array’s visitors. While the old panels were glass and subject to occasional cracking, the new panels are an aluminum polyester Teflon sandwich, with the solar cells in between the top and bottom layers. This new configuration is much lighter (27 pounds vs 45 pounds for the glass panels), more rugged, and more resilient to the ever-changing at-sea conditions than the glass version it is replacing.
The new panels are also flexible, rather than rigid like glass, which created another challenge to for the Engineering Team. They designed a special back for the panel with struts to provide greater support and more weight distribution as the 2,500-pound visitors flop onto the arrays. The lighter weight of the panels is giving the team more flexibility in placement of the panels on the moorings.
Said Reine, “We are so pleased to have these new and improved “off-the-shelf” solar panels operational. Two panels are now in place on Pioneer Array moorings, and another eight panels have been shipped to the Endurance Array, where they will be greeted by their 2,500-pound interlopers.”
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Low Dissolved Oxygen off Washington and Oregon Coast Impacted by Upwelling in 2017
In the summer of 2020, the Rutgers University Ocean Data Labs project worked with the Rutgers Research Internships in Ocean Science to support ten undergraduate students in a virtual Research Experiences for Undergraduates program. Rutgers led two weeks of research methods training and Python coding instruction. This was followed by six weeks of independent study with one of 13 research mentors.
Dr. Tom Connolly (Moss Landing Marine Labs, San Jose State University) advised Andrea Selkow from Austin College, Texas on her study of dissolved oxygen (DO) off the Washington and Oregon coasts using the OOI Endurance Array.
Selkow evaluated DO data from Endurance Array Surface Moorings during 2017 and 2018. She presented this work as a poster at the conclusion of her summer REU. Selkow focused on the question: Are there similarities in the dissolved oxygen concentrations off the coast of Oregon and Washington during a known low oxygen event? She also considered why there might exist differences based on the spatial variability of wind stress forcing, i.e., do the strong Oregon winds cause dissolved oxygen concentrations to be lower at the Oregon mooring compared to the Washington moorings. Finally, she reviewed the data and tried to answer whether the oxygen data were accurate or affected by biofouling.
She used datasets from the OR and WA Inshore Shelf Mooring time-series and WA Shelf Mooring time-series from Endurance Array. Her focus was on the seafloor data because that is where the lowest oxygen concentrations were expected to be observed.
Selkow focused her attention on low DO observed in the summer of 2017. While Barth et al. (2018) presented a report on these data for one event in July 2017, she expanded the analysis to include the Washington shelf and inshore moorings. She plotted time series data and used cruise data to validate these time series. While overall seasonal trends in DO were similar, she found dissolved oxygen is routinely more quickly depleted off the coast of Oregon than Washington during a low oxygen event (Figure 25). She also looked at the cross-shelf variability in DO time series and found dissolved oxygen is more quickly depleted at the shelf mooring than at the inshore shelf mooring. Upwelling is known to drive the low oxygen events and she inferred that the weaker southward winds over the Washington shelf may be why DO decreases at a slower rate off Washington than Oregon.
References
Barth, J.A., J.P. Fram, E.P. Dever, C.M. Risien, C.E. Wingard, R.W. Collier, and T.D. Kearney. 2018. Warm blobs, low-oxygen events, and an eclipse: The Ocean Observatories Initiative Endurance Array captures them all. Oceanography 31(1):90–97,
Selkow, A. and T. Connelly. Low Dissolved Oxygen off Washington and Oregon Coast Impacted by Upwelling in 2017, Accessed 13 Jan 2021.
Read MoreEndurance Array Measures Impact of Forest Fire Smoke
On September 8th 2020, wildfires spread quickly across western Oregon causing tremendous damage and shrouding the region with smoke for more than a week. Smoke from these fires, driven by an extreme Santa Ana-type easterly wind event, could be seen from satellites (figure 1). The smoky air moved directly across the path of the Coastal Endurance Array. A data view of this phenomenon is available here.
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Beginning on the 8th, strong, dry offshore winds blew past the Oregon Shelf Surface Mooring (CE02SHSM) 10 nautical miles west of Newport, which measured the lowest relative humidity values (<18%) since it was first deployed in April 2015 (panels a & b). These winds were followed by a week of reduced sunlight (panel c). Six meters below the surface, sunlight was reduced by the red smoke more in some colors than in others (panel d). Closer to shore at the Oregon Inshore site, light levels were measured throughout the water column by an OOI coastal surface piercing profiler (panel e). The smoky air had relatively high concentrations of carbon dioxide (panel f). Other Coastal Endurance Array sensors, such as bioacoustic sonars, also may have measured additional effects from these fires.
At the coast, the smokiest air cleared after a few days, although air particulates were elevated for more than a week (panel g). During the worst of the smoke, the iconic bridge over Yaquina Bay in Newport was hardly visible (figure 2). In Corvallis, 100 km inland and in the center of the Willamette Valley, unhealthy air blanketed the town for 10 days. These measurements are but one example of the type and quality of data being continuously collected by the Coastal Endurance Array.
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This article was written by Craig Risien and Jonathan Fram of the Coastal Endurance Array team.
Non-OOI data sources
NASA satellite images: https://earthobservatory.nasa.gov/images/147261/a-wall-of-smoke-on-the-us-west-coast
Florence air quality: https://oraqi.deq.state.or.us/home/map
Corvallis and Lincoln City air quality: https://www.purpleair.com/
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Delineating Biochemical Processes in the Northern California Upwelling System
Excerpted from the OOI Quarterly Report, 2022.
[media-caption path="/wp-content/uploads/2020/10/Endurance-Array-Science-Highlight.png" link="#"]Figure 19: Regional T/S variability at the Washington offshore profiling mooring. The end member Pacific Subarctic Upper Water (PSUW) and Pacific Equatorial Water (PEW) masses are indicated on each plot at the left and right respectively. T/S at the mooring is a mixture of PSUW and PEW. The left plot shows the seasonal variability. The right plot shows interannual variability in summer. Interannual variability from 100-250m exceeds seasonal variability. In 2015, T/S at the mooring is closer in character to climatological averages at Vancouver Island, BC while in 2018, T/S at the mooring is similar to that south of Newport, OR. Figure from Risien et al. adapted from Thomson and Krassovski (2010).[/media-caption]
Risien et al. (2020) presented over five years of observations from the OOI Washington offshore profiling mooring. First deployed in 2014, the Washington offshore profiler mooring is on the continental slope about 65 km west of Westport, WA. Its wire Following Profiler samples the water column from 30 m depth down to 500 m, ascending and descending three to four times per day. Traveling at approximately 25 cm/s, the profiler carries physical (temperature, salinity, pressure, and velocity) and biochemical (photosynthetically active radiation, chlorophyll, colored dissolved organic matter fluorescence, optical backscatter, and dissolved oxygen) sensors. The data presented included more than 12,000 profiles. These data were processed using a newly developed Matlab toolbox.
The observations resolve biochemical processes such as carbon export and dissolved oxygen variability in the deep source waters of the Northern California Upwelling System. Within the Northern California Current System, over the slope there is a large-scale north-south variation in temperature and salinity (T/S). Regional T/S variability can be understood as a mixing between warmer, more saline Pacific Equatorial Water (PEW) to the south, and fresher, colder Pacific Subarctic Upper Water (PSUW) to the north. Preliminary results show significant interannual variability of T/S water properties between 100-250 meters. In summer, interannual T/S variability is larger than the mean seasonal cycle (see Fig 19). While summer T/S variability is greatest on the interannual scale, T/S does covary on a seasonal scale with dissolved Oxygen (DO), spiciness and Particulate Organic Carbon (POC). In particular, warmer, more saline water is associated with lower DO in fall and winter.
Risien, C.M., R.A. Desiderio, L.W. Juranek, and J.P. Fram (2020), Sustained, High-Resolution Profiler Observations from the Washington Continental Slope , Abstract [IS43A-05] presented at Ocean Sciences Meeting 2020, San Diego, CA, 17-21 Feb.
Thomson, R. E., and Krassovski, M. V. (2010), Poleward reach of the California Undercurrent extension, J. Geophys. Res., 115, C09027, doi:10.1029/2010JC006280.
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