Posts Tagged ‘Coastal Endurance Array’
Tagging and Tracking Large Fish Along the PNW Coast
A Navy-funded project is currently monitoring Pacific Salmon along the coasts of Oregon and Washington, using specialized tracking technology to better understand fish movements in near-real time. This effort, led by Dr. Taylor Chapple of Oregon State University, is part of the Marine Species Monitoring initiative, supported by the U.S. Navy Pacific Fleet.
While separate from the U.S. National Science Foundation’s Ocean Observatories Initiative (OOI) cruises, this project takes advantage of OOI’s Endurance Array moorings by placing Vemco VR2C tag readers on select moorings to detect and track tagged fish. The collected data provides valuable insights that could benefit commercial fishers, marine conservation efforts, and naval operations.
Tracking Salmon in Real-Time
As part of this initiative, researchers are tagging Pacific Salmon and tracking their movements using Vemco VR2C tag readers. These specialized instruments have been deployed on three OOI Endurance Array moorings: the Oregon Inshore Surface Mooring (CE01ISSM), the Washington Inshore Surface Mooring (CE06ISSM), and the Washington Shelf Surface Mooring (CE07SHSM).
When a tagged fish approaches one of these moorings, the tag reader records the encounter and transmits the data to shore within hours. This near-real-time data can be useful for commercial fishers, military operations, and other maritime stakeholders operating in the Pacific Northwest.
Expanding the Scope: Tracking Other Marine Life
Beyond salmon, the tag readers detect other marine species that have been tagged through separate research projects. These include sharks tagged from California to Alaska, sturgeon, other large fish, and even Dungeness crabs. The data collected from these detections is shared through OOI’s raw data server, contributing to a growing body of research on marine life movements in the region.
Data Access
To make the data easily available, each mooring with a tag reader generates a CSV file whenever it transmits data. These files have been combined into larger datasets, organized by mooring deployment, allowing researchers to analyze fish migration patterns and ecosystem dynamics.
By using OOI’s moorings for data collection, this project enhances our understanding of large fish movements along the Pacific Northwest coast, demonstrating the value of integrated ocean monitoring and advanced tagging technology.
To learn more and access the full dataset, visit the Tagging and Tracking of Large Fish Along the PNW Coast webpage.
Bloom Compression Alongside Marine Heatwaves Contemporary with the Oregon Upwelling Season
Black et al. (2024) examine the impacts of marine heatwave (MHW) events on upwelling-driven blooms off the Oregon coast. They combine OOI data from Endurance moorings off Oregon with satellite data and indices of upwelling and MHW presence to determine how MHW’s impact these blooms. Their work focuses on MHWs and coincident events that occurred off Oregon during the summers of 2015–2023. They found the presence of MHW’s limited the offshore extent of phytoplankton blooms. In late summer 2015 and 2019, both documented MHW years, coastal phytoplankton biomass extended on average 6 and 9 km offshore of the shelf break along the Newport Hydrographic Line, respectively. During years not influenced by anomalous warming, coastal biomass extended over 34 km offshore of the shelf break. Reduced biomass also occurs with reduced upwelling transport and nutrient flux during these anomalous warm periods. However, the enhanced front associated with a MHW aids in the compression of phytoplankton closer to shore. Over shorter events, heatwaves propagating far inshore also coincide with reduced chlorophyll a and sea-surface density at select cross-shelf locations, further supporting a physical displacement mechanism. Paired with the physiological impacts on communities, heatwave-reinforced physical confinement of blooms over the inner-shelf may have a measurable effect on the gravitational flux and alongshore transport of particulate organic carbon. Black is a PhD student at Oregon State University and notes that all data used in the paper, including of course OOI data, are open source. They provide details regarding data access methods and intermediate processing steps along with code modules to reproduce the work at https://github.com/IanTBlack/oregon-shelf-mhw.
Black et al. focus much of their analysis on the Oregon Offshore mooring, CE04 (Fig. x). Here they show individual warm events aligned with periods where Chl a was much lower than the time-series average and the climatological mean. The analysis period for 2019 had the lowest average Chl a across all years. From the CE04-derived Chl a climatology, they observed an occurrence of a regular spring bloom (April) and a summer bloom (September). The peak of the summer bloom appears contemporary with the warmest time of year at CE04, and years 2019 and 2023 were the only years that experienced MHWs during this same period. The summer blooms of 2019 and 2023 at CE04 were also noticeably suppressed and difficult to differentiate from surrounding Chl a values.
[caption id="attachment_35688" align="alignnone" width="624"] Figure 28: Ocean Observatories Initiative (OOI) CE04, Coastal Upwelling Transport Index (CUTI), and Biologically Effective Upwelling Transport Index (BEUTI) time series between 2015 and 2023. Daily mean values are in light blue. Red vertical spans indicate potential marine heatwave (MHW) events and gray vertical spans indicate the time between the spring and fall transition dates. A centered 11-d rolling mean was applied to smooth the data (black).[/caption]
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Reference:
I Black, IT, Kavanaugh, MT, Reimers, CE. “Bloom compression alongside marine heatwaves contemporary with the Oregon upwelling season.” Limnology and Oceanography, no. (2024): First published: 16 December 2024, https://doi.org/10.1002/lno.12757
Read MoreExploring the Coastal Surface Piercing Profiler (CSPP): Capabilities, Challenges & Impact
The Coastal Surface Piercing Profiler (CSPP) is an important component of the Ocean Observatories Initiative (OOI), uniquely designed to collect high-resolution data from the ocean’s surface to the seafloor over the Oregon Shelf. Importantly, as the name implies, the CSPP does not stop at the ocean surface but some of its sensors actually pierces the interface into the near surface atmosphere. Operating in a highly dynamic environment, the CSPP provides valuable datasets that enhance our understanding of ocean-atmosphere interactions, nearshore processes, and biological activity in the upper water column.
In this interview, Jon Fram, co-PI and Program Manager for the Endurance Array (EA), explores the technical capabilities of the CSPP, the difficulties of operating in dynamic coastal conditions, and the significance of its unique datasets. With its ability to profile up through the air-sea interface and its collection of advanced sensors, the CSPP bridges critical gaps in ocean observation. Jon discusses the practical realities of deploying and maintaining the profiler, including a notable recovery effort that illustrates the complexity of coastal oceanographic work.
How does the CSPP operate in such a dynamic environment, and what are some of the challenges associated with deploying and maintaining it?
In between profiles, CSPPs park near the seafloor where currents from waves and tides are relatively calm. As CSPPs winch themselves up to the air-sea interface, they measure winchline tension and they alter their profiling speed to keep the tension constant. This behavior enables CSPPs to surface when waves are up to 3 meters high without the winchline over-wrapping or experiencing snap loads. We monitor conditions so CSPPs don’t profile when seas are too rough. Most of a CSPP’s battery energy goes to operating its winch, so CSPPs need to be recovered/redeployed every 2-3 months and they are limited to 2-4 profiler per day during each deployment (when conditions are sufficiently calm).
What types of sensors and instruments are on the profiler, and what specific data do they collect?
CSPPs average 25 cm/s as they profile upwards. Their CTDs sample at 16 Hz, which corresponds to a measurement every 1.5 cm. Their ~1 Hz instruments include dissolved oxygen (DOSTA), point velocity (VELPT), nitrate (NUTNR), spectral irradiance (SPKIR), photosynthetically active radiation (PARAD), and chlorophyll-a—optical backscatter—CDOM (FLORT). The CSPP is a particularly useful platform for the optical attenuation and absorption instrument (OPTAA), which can be used to characterize phytoplankton communities at the top of the water column.
What are the unique capabilities of the CSPP, and how do its datasets differ from those collected by other platforms within the OOI?
The CSPP is OOI’s only profiler that samples up to the air-sea interface.
How has the profiler contributed to understanding the relationship between atmospheric and oceanic processes in the area?
So far, OOI’s CSPPs have been used to fill in time gaps in mooring data and to fill in spatial gaps between mooring near-surface (NSIF) and benthic (MFN) data. Inshore and shelf CSPP data have been used together to calculate cross-shore exchange of nitrate, which is increased each spring due to coastal upwelling. CSPPs measure at the air-sea surface, so their measurements could be used to validate satellite data.
How could the near-time data transmission from the profiler benefit research efforts or inform stakeholders such as fisheries, conservation groups, or local communities?
Datasets are available within a week after each deployment. They can telemeter all data when they are on the surface at the top of each profile, however, we transfer only data needed for operational decisions to reduce the chance of winchline fouling.
Can you share an anecdote about a particularly challenging or rewarding moment during the deployment, maintenance, or operation of the profiler?
One challenging moment occurred 06 April 2019. During a storm, rough seas (~7m significant wave height, >1 m/s currents) dislodged our 25m depth Oregon Inshore CSPP and deposited it 75 nm north on a pocket beach in Ecola State Park. We climbed down to it, pulled it above the high tide line, disassembled it, and packed it out piece-by-piece up a steep trail in pouring rain. The Endurance Array inshore CSPP and adjacent surface mooring measure the northward fresh/turbid surface current that hugs the Pacific Northwest coast during winter, and which strengthens during storms. This is one example of how the CSPP data can be used to improve our wind, wave and current forecast models.
[caption id="attachment_35671" align="alignnone" width="640"]
Deployment of CSPP. (c) Jon Fram[/caption]
[caption id="attachment_35670" align="alignnone" width="640"] Beach recovery effort. Pictured: Ian Black, OSU. (c): Jon Fram[/caption]
Read More Exploring OSU’s Ocean Observatories Initiative Through Virtual Reality
Students and faculty at the Oregon Institute of Marine Biology (OIMB) had the opportunity to participate in a 360-degree virtual reality (VR) tour of Oregon State University’s (OSU) U.S. National Science Foundation’s Ocean Observatories Initiative (OOI) Ocean Observing Center in Corvallis. Led by Dr. Jonathan Fram, co-PI and project manager for the OOI Endurance Array, the tour provided an in-depth look at the advanced instruments and systems used to study the ocean’s physical, chemical, geological, and biological processes.
Hosted remotely, the tour allowed participants at OIMB to engage with the facility through live-streamed video, filmed using cutting-edge VR technology by Darryl Lai from OSU Productions. This immersive format enabled attendees to explore the facility virtually and ask real-time questions, making it an accessible and informative experience.
The event was complemented by guest lectures from visiting oceanographers Dr. Léo Mahieu and Dr. Mareike Körner, postdoctoral researchers from OSU’s College of Earth, Ocean, and Atmospheric Sciences (CEOAS). They shared insights about their research and career trajectories, offering inspiration and guidance to students interested in oceanography.
This unique event showcased the innovative tools and collaborative efforts that the OOI is using to advance modern ocean research. Check out the recording of the OSU/OOI tour here.
Read MoreImpact of Ocean Model Resolution on Temperature Inversions in the Northeast Pacific Ocean
Temperature inversions are a local vertical minimum in temperature located at a shallower depth than a local maximum. In the Northeast Pacific, several water masses and multiple mechanisms for transforming or advecting ocean temperature (cold air events, upwelling, river discharge, cross-shelf eddy transport) create favorable conditions for temperature inversions. Modeling these temperature inversions is challenging. Osborne et al. (2023) analyze observations from 2020 and 2021 to characterize inversions in the Northeast Pacific. The data for these observations come largely from OOI Endurance Array gliders accessed through the GTS database. They compare the observed inversions to model results from the U.S. Navy’s Global Ocean Forecast System version 3.1 (GOFS 3.1) and two instances of the Navy Coastal Ocean Model. Temperature inversions are observed to be present in about 45% of profiles with temperature minimums between 50 – 150 m, temperature maximums between 75 – 175 m, and inversion thickness almost entirely less than 40 m. Modeled temperature inversions are present in only about 5% of model-observations comparisons, with weaker, shallower minimums. This is attributed to two primary causes: coarse model resolution at the inversion depth and the assimilation process which low-pass filters temperature, making inversions weaker. Osborn et al. identify additional work to test the impact of vertical grids on improving model performance.
[caption id="attachment_34977" align="alignnone" width="392"] Maps of inversion counts for observed profiles collected during 2020-2021 and analyzed in this work. Profiles have been filtered to be offshore of the 200 m isobath and to only one profile per collection platform per day (e.g., one profile per glider per day). Black line near the coast marks the 200 m isobath. Light gray indicates no profiles collected during the study period.[/caption]
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References:
J. Osborne V, C. M. Amos and G. A. Jacobs, “Impact of Ocean Model Resolution on Temperature Inversions in the Northeast Pacific Ocean,” OCEANS 2023 – MTS/IEEE U.S. Gulf Coast, Biloxi, MS, USA, 2023, pp. 1-8, doi: 10.23919/OCEANS52994. 2023.10337390.
Read MoreUG2 Workshop ’24: A Collaborative Hub for Underwater Glider Innovation
The UG2 Workshop ’24, held from September 10-12 on the University of Michigan campus, brought together leading researchers, industry professionals, and practitioners to advance the capabilities and collaborative efforts of the underwater glider community. National Science Foundation Ocean Observatories Initiative (OOI) attendees included Ed Dever, Principal Investigator of the Northeast Pacific Endurance Array (EA), Peter Brickley, Senior Engineer with the Coastal and Global Scale Nodes (CGSN), and EA glider lead Stuart Pearce and glider tech Jonathan Whitefield. Over the course of three days, OOI participants contributed to in-depth discussions on data management, operational best practices, and emerging technologies, laying the foundation for future advancements in ocean monitoring and glider operations.
Workshop Goals and Objectives
The primary objective of UG2 is to foster a cohesive community that promotes the sharing of glider mission resources within the U.S. and internationally. The 2024 Workshop aimed to:
- Harmonize Glider Efforts: Improve data management and foster partnerships while documenting best practices to enhance collaboration.
- Share New Developments: Highlight recent advancements in sensors, glider technologies, and novel applications.
- Refine Operational Activities: Enhance strategies for sustained ocean observations and explore the impact of glider data on ocean modeling.
- Identify Action Items and Needs: Address communication gaps and improve UG2’s communication platforms for the future.
- Network with Glider Users: Facilitate interactions among U.S. and international glider users to strengthen partnerships.
Key Highlights
The workshop featured several interactive components that fostered deep engagement and collaborative dialogue:
- Liesl Hotaling’s Plenary Talk and Breakout Session: Liesl Hotaling’s plenary talk and subsequent breakout session focused on developing microcredentials for ocean technology professionals. This initiative aims to address workforce needs by creating stackable credentials that recognize core competencies. Her session, co-led with Josh Kohut, invited attendees to discuss the application of these credentials in building capacity for glider maintenance and piloting.
- Data Management Sessions (Day 2): A significant portion of Day 2 was dedicated to addressing challenges in glider data management. Facilitators Jennifer Bowers, Leila Baghdad-Brahim, and Jennifer Sevadjian led discussions on best practices for data collection, registration, and sharing. The sessions provided valuable insights into the U.S. IOOS National Glider Data Assembly Center (DAC) and efforts to standardize glider data handling, ensuring efficient management of multidimensional data. All OOI glider data are routinely reported to the DAC using code developed by Stuart Pearce and others.
- Sustained National Glider Network Session (Day 2): Daniel Rudnick and J. Xavier Prochaska facilitated this session, which emphasized the importance of a sustained glider-based observation network within the Global Ocean Observing System (GOOS). Participants explored the feasibility of creating a coordinated network that integrates coastal and basin-scale observations, building on previous efforts by the Ocean Gliders Boundary Ocean Observing Network (BOON). The OOI’s Endurance Array lines are part of the BOON along the US Pacific coast.
- Poster Presentations: The poster sessions showcased a wide range of research and operational insights. OOI contributed two posters.
- Stuart Pearce et al. presented a poster on “OOI In-Air Oxygen Calibration Adjustments and Improved Oxygen Sensor Mount,” highlighting advancements in sensor calibration for improved accuracy.
- Peter Brickley et al. showcased “OOI Glider Operations in the Mid-Atlantic Bight,” detailing operational strategies and findings from extensive glider deployments in this dynamic region.
Outcomes and Next Steps
The workshop successfully facilitated deep engagement and collaboration, resulting in several key outcomes:
- Enhanced Data Management Practices: The data management sessions provided a comprehensive overview of current challenges and future directions, including early-stage data federation efforts aimed at harmonizing international standards.
- Support for a Sustained Glider Network: The discussions around a national glider network laid the groundwork for future collaboration, emphasizing the need for long-term, high-resolution coastal and deep ocean observations.
- Advancements in Professional Training: The workshop underscored the importance of developing innovative, stackable educational opportunities to build capacity in the blue economy. These efforts aim to enhance workforce skills and provide diverse learning pathways for individuals seeking careers in ocean technology.
[caption id="attachment_34904" align="alignnone" width="640"]
Stuart Pearce (OSU Endurance, left), Brian VerWey (OSU research glider group, center), and Jonathan Whitefield (OSU Endurance, right) pose during discussions around Brian’s poster.[/caption]
Read More Subsurface Acoustic Ducts in the Northern California Current System
Xu et al.’s analysis of the hydrographic data recorded along the U.S. Pacific Northwest coastline leads to the identification of a secondary subsurface acoustic duct. A numerical simulation based on the sound-speed field determined from OOI Coastal Endurance and APL-UW glider CTD data suggests that the presence of the duct has major impact on sound propagation at a mid-range frequency of 3.5 kHz in the upper ocean (Figure 31). Specifically, the ducting effect is evident in the trapping of sound energy and the consequent reduction in transmission loss within the duct. Glider observations show that the duct is a large-scale phenomenon that extends hundreds of kilometers from the outer continental shelf to regions offshore of the continental slope. The axis of the duct shoals onshore from between 80 and 100 m depth offshore of the continental slope to less than 60 m over the shelf. Analysis of the sound-speed profiles determined from glider CTD data suggests that the prevalence of the duct decreases onshore, from over 40% in regions offshore of the continental slope to less than 5% over the shelf. In addition, analysis of the long-term time series of sound-speed profiles determined from the CTD data recorded over the shelf slope off the Washington Coast suggests that the duct is more prevalent in summer to fall than in winter to spring. Furthermore, examination of concurrent OOI Coastal Endurance Array (Washington Offshore Profiling Mooring) observations of sound speed and flow velocity indicates that the duct observed over the shelf slope is associated with a vertically sheared along-slope velocity profile, characterized by equatorward near-surface flow overlaying poleward subsurface flow.
[caption id="attachment_34581" align="alignnone" width="462"] (adapted from Fig. 3 of Xu et al., 2024) (a) The sound-speed field obtained from the CTD data recorded by an OOI-CEA coastal glider during 06-16 October 2018. The contour lines are potential density (in kg/m3). The magenta dots mark the locations of the local sound-speed minima along the axis of the subsurface duct. (b) The trajectory of the Seaglider. The red dot marks the location of the OOI-CEA Washington Offshore profiler mooring. The bathymetry contour lines mark seafloor depths in 100 m increments between 10 and 500 m and then in 500 m increments between 500 and 3000 m. (c) The vertical sound-speed profile at 20 km along-track distance. The local sound-speed minimum at the axis of the duct is labeled.[/caption]
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References:
Guangyu Xu, Ramsey R. Harcourt, Dajun Tang, Brian T. Hefner, Eric I. Thorsos, John B. Mickett; Subsurface acoustic ducts in the Northern California current system. J. Acoust. Soc. Am. 1 March 2024; 155 (3): 1881–1894. https://doi.org/10.1121/10.0024146
Read MoreGraduate Students Apply Now for Endurance Fall Shipboard Experience
Upcoming cruise volunteer opportunity on NSF Ocean Observatories Initiative Coastal Endurance Array Expedition
When: Leave Newport, Oregon on October 4, 2024; return to Newport on October 20, 2024
Applications Due: August 30, 2024
There is an opening for a student volunteer in the Fall 2024 as part of the U. S. National Science Foundation Ocean Observatories Initiative (OOI) Coastal Endurance Array on R/V Sikuliaq. The Coastal Endurance Array team will deploy and recover oceanographic moorings, profilers and gliders off Washington and Oregon. Seven surface moorings will be deployed and recovered along with up to four profilers and six gliders. The team will also conduct CTD (Conductivity, Temperature, and Depth) casts, with bottle sampling, and collect underway ship data for comparison to data from deployed equipment.
The selected volunteer will have the opportunity to assist in the deployment and recoveries of moorings and water sample processing. They will also have opportunities to work directly with OOI data. The cruise will consist of two legs, each lasting about 8 days. Interested applicants can apply to participate on either or both legs. Domestic (within the USA) travel reimbursement is possible.
The primary goal of this program is to provide graduate students currently completing (or who have recently completed) a degree in a field of oceanographic research with the opportunity to participate in a research cruise. The participant will be a member of the scientific party and be involved in data collection and all other activities at sea. It is envisioned that the individual will be familiar with the science to be conducted at sea, and thus, form new collaborations and potentially develop new research directions. To be eligible to participate, the individual must either currently be studying at a U.S.-based institution or be a recent graduate, and have either a U.S. Passport or an applicable U.S. Visa.
Questions and application materials should be sent to Edward.Dever@oregonstate.edu. Application materials are:
- a CV or resume
- a one page letter of interest describing how this opportunity fits their professional and/or research interests
- contact information for two references.
For a first-hand view of what to expect at sea, check out this video.
[media-caption path="https://oceanobservatories.org/wp-content/uploads/2024/06/Sikuliaq-1.jpeg" link="#"]R/V Sikuliaq, University of Alaska Fairbanks.[/media-caption] Read MoreIan Black: Taking Inspiration from OOI
As an undergraduate at Oregon State University (OSU), Ian Black attended an oceanography course taught by the OOI’s Coastal Endurance Array Principal Investigator Ed Dever, where he was introduced to key oceanographic concepts and the observational capacity of the OOI. Black was so intrigued by the work that he approached Dever and asked about an internship with the OOI Endurance Array.
“Initially it was scraping barnacles, turning wrenches, very dirty and manual labor,” explained Black. “And I liked it. The project and its mission made sense to me.” The OOI provided Black with his first experience at sea, the Regional Cabled Array’s VISIONs cruise in 2015, where he sailed with another OOI alum Katie Bigham. Toward the end of his internship and undergraduate program, Black was interested in continuing to work on the Endurance Array and was encouraged to pursue a master’s degree. Throughout graduate school, Black continued to work part-time on the Endurance Array, continuing to scrape barnacles, but also gained some experience in electronics and coding.
In 2018, Black received his M.S. in Marine Resource Management and was hired on as an Endurance Array technician. Between 2018 and 2021, Black focused primarily on the Coastal Surface Piercing Profilers that are deployed at the CE01, CE02, CE06, and CE07 sites located off Oregon and Washington. He also provided assistance with the large coastal surface moorings and gliders during downtime and cruises.
Not one to sit still too long, Black decided to pursue a PhD, again at OSU in 2021. Black was originally brought on by his co-advisors, Dr. Clare Reimers and Dr. Maria Kavanaugh, to focus on the bio-optical sensors that are to be deployed on the NSF’s new Regional Class Research Vessels. While waiting for the deployment of these vessels, Black has developed a newfound interest in marine heatwaves. Currently, he and his advisors have a manuscript under review where they use OOI Endurance Array data to explore the biophysical impacts of marine heatwaves on phytoplankton.
[media-caption path="https://oceanobservatories.org/wp-content/uploads/2024/05/Profiler-Victory-2-scaled.jpg" link="#"]Left to Right: Jon Fram, Ian Black, Alex Wick, and Steve Lambert pose with a recently recovered profiler. Credit: Oregon State University.[/media-caption]For the next chapter in his PhD dissertation, Black plans to again use OOI data from the Endurance Array to explore the finer scale effects of marine heatwaves over the Oregon shelf. “There are a lot of high-resolution data products from the moorings, profilers, and gliders that could be combined to tell an interesting story”, Black said. In particular, there are some “some really interesting still images from the camera located at the shelf site that coincide with events or phenomena that are commonly introduced in oceanography courses, much like the class Ed (Dever) taught all those years ago. Seeing these things with real data really reinforces those core oceanographic concepts.” Black hopes that this work will end up as a second manuscript, but at the very least “the code and results can be used as a tool, perhaps in the classroom, to show students that the concepts they learn about are supported with modern data.” Black added that has been instrumental in his PhD research. He uses it between several times per week to review, process, and assess data.
“The OOI Endurance Team has been supportive at every stage of my career so far, not just the OOI ones. “It’s a great place to work and Ed (Dever) and Jon (Fram) work hard to keep people invested in the project.” The few years working as a technician and almost decade of interaction with the OOI has been an important part of my development. Black added, “I even missed the camaraderie so much that I recently volunteered to join the 20th deployment of the Endurance Array (EA20) this past spring.” As an undergraduate, Black’s first Endurance cruise was EA5.
Black brings an interesting perspective to OOI data. He now looks at it from the vantage point of a scientist and how it can be used to answer questions, as well as from an engineering viewpoint on how data are collected in such a unforgiving marine environment. “The amount of data offered by OOI is daunting and is going to take anyone, regardless of data analysis skill level, a long time to look through. In my opinion, it is particularly important for graduate students, who might have more time to look at the data, to just start looking to see what they can find.” Black gave an example of the richness and uniqueness of data available. In 2019 as the Blob 2.0 marine heatwave was expanding in the Northeast Pacific, he was deploying an OOI profiler at the Oregon shelf site (CE02SHSP). Due to platform malfunction, operator error, or a combination of, the profiler decided to surface every 20 minutes for 2 days instead of the typical 12 hours for 2 months. Black hopes that something interesting could be found in this data and thinks it could make for a good term project for a class. “It’s very interesting data and it’s public’s data.” If Black stays in academia, he plans to encourage his students to explore open data collected by groups such as the NSF’s OOI.
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Widespread and Increasing Near-bottom Hypoxia in Pacific NW Coastal Ocean
Barth et al. (2024) examined the 2021 summer upwelling season off the United States Pacific Northwest coast. Upwelling was unusually strong leading to widespread near-bottom, low-oxygen waters. During summer 2021, an unprecedented number of ship- and underwater glider-based measurements of dissolved oxygen were made in this region. Near-bottom hypoxia, that is dissolved oxygen less than 61 µmol kg−1 and harmful to marine animals, was observed over nearly half of the continental shelf inshore of the 200-m isobath, covering 15,500 square kilometers. A mid-shelf ribbon with near-bottom, dissolved oxygen less than 50 µmol kg−1 extended for 450 km off north-central Oregon and Washington. Spatial patterns in near-bottom oxygen are related to the continental shelf width and other features of the region. Maps of near-bottom oxygen since 1950 show a consistent trend toward lower oxygen levels over time. The fraction of near-bottom water inshore of the 200-m isobath that is hypoxic on average during the summer upwelling season increases over time from nearly absent (2%) in 1950–1980, to 24% in 2009–2018, compared with 56% during the anomalously strong upwelling conditions in 2021. Widespread and increasing near-bottom hypoxia is consistent with increased upwelling-favorable wind forcing under climate change.
As part of their analysis, Barth et al. (2024) used NSF OOI glider data from 2021 along the Newport Hydrographic Line along with other data indicated in Fig x.. Near-bottom dissolved oxygen data from each survey as a function of time show the typical decrease of minimum values as the summer hypoxia season proceeds (Fig. x). High DO values are measured by the OOI gliders early in the upwelling season when winds were relaxed or downwelling-favorable early in the upwelling season, and by the Oregon Department of Fisheries and Wildlife (ODFW) survey that focused on very shallow (water depths of 50 m or less), inshore waters.
[media-caption path="https://oceanobservatories.org/wp-content/uploads/2024/05/Endurance-Figure.png" link="#"]Figure x Near-bottom dissolved oxygen as a function of time during the 2021 summer upwelling season.[/media-caption]__________________
Reference:
Barth, J.A., Pierce, S.D., Carter, B.R. et al. Widespread and increasing near-bottom hypoxia in the coastal ocean off the United States Pacific Northwest. Sci Rep 14, 3798 (2024). https://doi.org/10.1038/s41598-024-54476-0
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