Research

The Southeast Area Monitoring and Assessment Program (SEAMAP) Shrimp/Groundfish trawl surveys are conducted throughout the Gulf of Mexico to provide fishery-independent monitoring and assessment information on shrimp and groundfish assemblages associated with low relief soft-bottom habitats. These data are essential to the management of the fisheries resources in the Gulf of Mexico. Louisiana Department of Wildlife and Fisheries (LDWF), as well as SEAMAP state partners, sample in conjunction with the National Marine Fisheries Service (NMFS) to provide a Gulf-wide trawl survey each summer and fall.

These cruises utilize funding provided by the University of Minnesota. Chief Scientists will be completing seed research cruises or using their ship time to take graduate and undergraduate students on the research vessel Blue Heron.

The ONR-funded Task Force Ocean: New England Seamounts Acoustics Effort is a multi-PI, multi-institution effort to understand the impact of geological, physical, and biological variability on acoustic scattering, propagation, attenuation, coherence, and inversion methods. This specific ship-time request involves a pilot test and engineering effort focused on assessing the capabilities of a towed instrument platform, Deep-See, and a REMUS 600, for performing measurements of acoustic scattering in the Gulf Stream meanders expected to influence the seamounts. The Gulf Stream plays a critical role in mediating the temporal and spatial variability of sub-mesoscale and finer scale physical oceanographic processes at the New England Seamounts. The New England Seamounts are a chain of over twenty submarine mountains that rise to a depth of around 1000-2000 m. The Seamounts are separated by geography and by physical oceanographic processes driven by the Gulf Stream. Processes such as meanders in the Gulf Stream, cold and warm core eddies, intense upwelling and circum-seamount eddies drive a diverse physical and biological environment at the Seamounts. Upwelling from flow over the rapidly changing bathymetry makes the Seamounts biological hotspots of increased productivity compared to the surrounding waters. At deep seamounts such as Atlantis II, this productivity manifests as a dense deep scattering layer (DSL) and a robust fish population on the flanks and summit of the seamount. The DSL at Atlantis II is coincident with the SOFAR channel and the abundance of organisms within DSLs changes on temporal scales from daily- in the form of diel vertical migration, to seasonally and inter-annually. The fish populations, both in the DSL and at the flanks and summit of the seamount, have gas filled swimbladders. Echoes from these fish can be the dominant source of reverberation over a range of important active Navy sonar frequencies (1- 10 kHz). Effects of absorptivity due to the gas-filled swimbladders on transmission loss at mid-frequencies can also be significant, as is the impact of complex scattering from large aggregations of gas bladder bearing fishes on echo-statistics. Changes to the phase of transmitted sound as it passes through fish populations can lead to errors in beam forming and target localization if not properly accounted for. Accounting for the biological populations in long range acoustic transmission at the seamounts suffers from a paucity of information about fish populations and the physical oceanographic processes that drive the distribution and abundance of acoustically important species. Due to their isolation, the deep-water seamounts in the New England Seamount chain are a relatively understudied part of the ocean. The environmental complexity associated with the seamounts poses increased challenges to the Navy ASW operations. This project focuses on understanding the impact of extreme spatial and temporal environmental variability on the scales of a few hundred meters to several 10s of kilometers as it pertains to long range propagation of Navy mid-frequency active sonar (MFAS) and low-frequency passive sonar.

Submerged archaeological resource assessment survey of Tract X-1352, offshore of Eglin Air Force Base. The project consists of a Phase I remote-sensing survey of approximately 1 square nautical mile (865 acres) of seafloor within the Gulf of Mexico. This work will be conducted out of SEARCH’s Maritime Archaeology Division, based in Pensacola, Florida. Dial Cordy and Associates will execute a Phase I remote-sensing survey of the tract. SEARCH will coordinate with the Eglin Cultural Resources Management Branch (CRM) and other installation personnel as necessary. Throughout the performance of this contract, SEARCH’s management staff will work closely with the staff of Argonne National Laboratory (Argonne) and Eglin Air Force Base (Eglin AFB) to ensure the work is conducted in accordance with the Statement of Work (SOW). All work required for this archaeological survey and reporting shall be completed and delivered to Argonne no later than April 3, 2025.

The very fast and dynamic ocean biological carbon pump (OBCP) plays a fundamental role in the global carbon cycle and in setting concentrations of atmospheric carbon dioxide. Photosynthetic organisms that that fuel the OCBP live and die on a week to week basis, and the resulting sinking (or export) of organic and inorganic carbon particles from the surface layer and consumption losses of these particles in deeper waters are similarly variable. Simply stated, the OCBP is poorly understood due to dependence on short- term, and seasonally and spatially limited ship observations; thus model estimates of its strength and future trajectory are highly uncertain. To address this gap, the investigators will engineer and sea-test two robotic Lagrangian Ocean Carbon Observer (OCO) floats capable of 8 month to multi-year missions, yet able to resolve flux processes on hourly to daily time scales and relay data in real time via satellite telemetry while operating anywhere in the ocean. The development of the OCO enables the identification of specific pathways and controls on the vertical transfer of particulate organic and inorganic carbon (POC and PIC) from the surface ocean to subsurface waters. The project logically follows on from the investigator’s development and successful deployment of robotic Lagrangian Carbon Explorer (CE) and Carbon Flux Explorer (CFE) floats, which measure optically POC and PIC concentration and flux variability to depths of 1000 m. A unique capability of the CFE is that it is able to measure the sinking flux of carbon carried by different sizes and classes of particles. The project will merge CFE and CE capabilities to create the OCO. The team will contribute to the development of a STEM workforce by engaging UC Berkeley undergraduates and one graduate student in all phases (development, laboratory, seagoing, and interpretive) of the project and in the class room. Specifically, CFEs and two new Ocean Carbon Observers (OCOs) that simultaneously measure both particle flux and concentration profiles will be constructed and test-deployed at sea in January 2023. During the times that these autonomous instruments drift at target depths within the upper kilometer (interrupted by transit to the surface for location and real time bidirectional telemetry), they will autonomously quantify the inherent optical properties and size distributions of sinking material captured. Bishop et al. (2016; Biogeosciences 13, 3019-3129, doi:10.5194/bg-13-3109) describe CFE capabilities and methodology for rendering raw OSR imagery to rigorously defined inherent optical measures of particle loading -- attenuance and cross-polarized photon yield. Bourne et al. (2019; Biogeosciences, 16, 1249-1264; doi:10.5194/bg-16-1249-2019) show that attenuance is strongly correlated (r^2 > 0.86) with POC and PN sampled at 150 m by sampler-equipped CFEs “(CFE-Cal floats)” over a broad range of particle flux and particle size distributions. Planned further deployment of the CFE-Cal floats to sample sinking material to depths of at least 500 m will enable validation of our calibration of the attenuance proxy and to enable a first calibration of the PIC optical flux proxy. Bourne et al. (2021; Biogeosciences, 18, 3053–3086, doi:10.5194/bg-18-3053-2021) demonstrate the unique capability of CFEs to resolve and quantify the vertical flux carried by different particle size classes in the mesopelagic; furthermore, they describe prototype algorithms that will lead to flux size-distribution analysis in real time on the CFEs. The project will enable fully autonomous long-term deployments of CFE and OCO systems in the global ocean. The involvement a commercial float vendor (MRV Systems) and sensor manufacturer (Seabird Scientific) may lead to a commercialization pathway for the OCO.

Systematic long-term (greater than a few decades in length) time-series observations of aquatic and terrestrial environments have led to a more comprehensive understanding of the natural ecosystem variability and have enabled an assessment of human impacts on ecosystem dynamics. Because of their ability to store and transport large amounts of heat and to absorb carbon dioxide from the atmosphere, the world's oceans play a critical role in modulating environmental conditions for the sustained well-being of both land-based and marine organisms including humans. Despite their recognized scientific and societal importance, long-term records of key ocean processes are rare. In 1988, two ocean time-series programs were established: one in the North Atlantic near Bermuda and the other, the Hawaii Ocean Time-series (HOT) program, near Hawaii. For the past three decades, teams of scientists based at the University of Hawaii have made critical measurements of the 'state of our sea.' These long-term observations have established a baseline against which future states can be compared. The ship-based HOT program complements other diverse ocean observation programs including remote-sensing via satellites, moored buoys, profiling floats, and autonomous underwater vehicles. All HOT program data are publicly available and are frequently used by researchers and policy makers around the world.

We aim to understand the transport, persistence and distribution of environmental DNA (eDNA) in marine environments from marine mammal targets. With support from the ONR Multidisciplinary University Research Initiatives (MURI) program, we will use ongoing and existing large-scale projects across the West Coast to understand eDNA on multiple spatial, vertical, and temporal scales, with a minimum of additional sampling effort. Our major objectives are: (1) to understand the fate and transport of eDNA and thereby interpret eDNA detections from marine mammals in a spatially and temporally explicit context; (2) to evaluate eDNA as a complement to -- or plausibly, as an alternative to -- traditional visual observations and acoustics detections for cetaceans; and, (3)To apply the lessons learned to map marine mammals along the US west coast using eDNA. As part of this effort we will integrate marine mammal eDNA sampling and detection protocols into quarterly CalCOFI (California Cooperative Oceanic Fisheries Investigations) ocean ecosystem monitoring cruises in the California Current Ecosystem. We will also pair eDNA marine mammal sampling with ongoing acoustic and visual surveys of marine mammals as part of the CalCOFI cruise plan. Collectively, these efforts will provide an unparalleled testbed for the validation and calibration of emerging eDNA sampling methods for cetacean detection and location prediction.

Conduct CalCOFI surveys off Southern California quarterly, two of these on UNOLS ships.

The California Current Ecosystem (CCE) Long-Term Ecological Research (LTER) site is a coastal upwelling biome and the site of a 73-year (ongoing) spatially-resolved ocean timeseries (CalCOFI) that has demonstrated physical forcing on multiple spatiotemporal scales with concomitant impacts on ocean biota. The CCE is part of the larger LTER Network, founded in 1980 by the National Science Foundation. CCE-LTER studies are making excellent progress towards diagnosing mechanisms of ecosystem change in a major upwelling ecosystem and developing a quantitative framework for forecasting future changes. Our field site is in the CA Current upwelling regime, centered around Point Conception, within the CalCOFI time series station plan. The CCE LTER field program includes several different elements: experimental process cruises, time series cruises (ship time augmented on existing CalCOFI cruises) and mooring servicing cruises to maintain the deep water CCE1 and CCE2 moorings. The science carried out on these field expeditions is highly interdisciplinary, involving elements of biological, chemical, and physical oceanography.

The science, technology, engineering and mathematics (STEM) workforce is crucial to the U.S. health and economy, yet retention rates in STEM fields are poor, and the Geoscience community in particular is faced with a looming workforce shortage. Moreover, the Geoscience community continues to lack the diversity of the population at large. The STEM Student Experiences Aboard Ships (STEMSEAS) project is a 3-year partnership between the Indiana University of Pennsylvania, Lamont Doherty Earth Observatory at Columbia University, and the University National Oceanographic Laboratory System (UNOLS) aimed at addressing three priorities: (1) increasing the number and diversity of students pursuing degrees and careers in geosciences; (2) preparing students for all possible career trajectories in the geosciences; and, (3) contributing to the evidence base for effective student engagement, learning and retention in STEM. The STEMSEAS project is achieving these goals by taking advantage of unused berthing capacity available on UNOLS vessels as they transit between U.S. ports in preparation for their next scientific expedition. These short (~5-7 days) transits offer a unique mobile classroom setting where undergraduate non-STEM, undecided-STEM, and geoscience majors can be exposed to geoscience professional practice and career exploration. By partnering with UNOLS and campus ?champions" at universities, including minority-serving institutions (MSIs) and historically black colleges and universities (HBCUs), the project sends diverse cohorts of students to sea with a small team of geoscience faculty and mentors. STEMSEAS is built on a pilot-project that sent three cohorts (~10 undergraduate students each) selected from an applicant pool of ~875 students on three different research vessels during 2016. The pilot-project demonstrated the logistical feasibility of the program, and showed through preliminary data a strong potential for positive impact. While at sea, the students engage in a variety of hands-on activities that incorporate geoscience content, lab exercises, data collection/analysis, career exploration, and discussion/reflection. Upon completion of a transit, each participant is required to complete a post-expedition project, which they present back at their home institution, write a short article about their experiences, and participate in post-expedition webinars with other cohort members. The STEM Student Experiences Aboard Ships (STEMSEAS) project is a 3-year initiative aimed at addressing three priorities: (1) increasing the number and diversity of students pursuing degrees and careers in geosciences; (2) preparing students for all possible career trajectories in the geosciences; and, (3) contributing to the evidence base for effective student engagement, learning and retention in STEM. Application materials and evaluation surveys are providing data to assess the impact of the STEMSEAS project on student knowledge of and attitudes toward the geosciences and geoscience careers. The STEMSEAS project is designed to add to the evidence base regarding what kinds of experiences and interventions help to increase retention and persistence in geoscience-related majors, and what strategies are most effective at increasing the number and diversity of students entering the geoscience workforce pipeline. By creating innovative learning experiences on board charismatic research vessels, STEMSEAS is gathering data on the effectiveness of novel approaches for engaging students who may never have considered the geosciences as a field of study or career, students who are interested in the geosciences but are unsure of what direction to go, and STEM-interested students who may not have considered the specifics of the geosciences. Through these immersive experiences, STEMSEAS is exploring the effectiveness of short-term but intense learning activities.

We propose to conduct an active-source seismic experiment across the Puerto Rico Trench (PRT), its outer rise, and across the island arc, plus a land passive-source experiment. Three wide-angle seismic reflection/refraction transects will be recorded across the PRT by OBS. The central OBS profile will extend to the accretionary prism south of Puerto Rico. Two other OBS profiles will run across the PRT at the eastern and western sections. Seven multichannel seismic (MCS) reflection lines will be collected, two parallel to and inland from the trench, and five parallel to the central OBS profile. An array of nodal land seismometers will be deployed across Puerto Rico. Work similar to that proposed here has never been conducted across the PRT because of the trench’s large water depth. This gap in scientific knowledge persists despite the PRT being part of the U.S. EEZ and the significant geological hazards for the region. To overcome this challenge this project is a collaboration with GEOMAR Helmholtz Centre for Ocean Research, Kiel, Germany. GEOMAR will provide ten (10) deep-water OBSs capable of operating to depths of up to 8,000 m (2 of them up to 9,000 m). We request the use of the 15-km-long MCS steamer of R/V Langseth , 31 short-period OBS instruments from US OBSIC for water depths <6,000 m, and land nodal seismometers from IRIS. Old Atlantic lithosphere subducts obliquely at the PRT under the Caribbean plate at <20 mm/yr. The PRT is associated with anomalous, and hitherto unexplained characteristics, such as the widest trench (below 6,000 m), the strongest negative gravity anomaly on Earth, and anomalous subsidence of the Puerto Rican north coast. Furthermore, the slab may be segmented and possibly torn. The proposed experiment aims at exploring three questions: (1) What is the shallow geometry of the subducting slab and its lateral continuity along the 500-km section of the trench? The expected results will help inform the potential for the PRT to generate a mega-earthquake and mega-tsunami, similar to the 2004 Sumatra earthquake and tsunami, impacting the Caribbean and U.S. Atlantic margins. (2) What is the degree and spatial extent of hydration of the Atlantic lithosphere entering the Puerto Rico Trench? Comparison with other old subduction zones with higher convergence rates and different pre-existing structure and composition will allow quantification of the hydration process. The PRT is also one of the very few locations in the world, where in situ crustal serpentine samples have been analyzed and dated. (3) Does the oceanic bivergent thrust system represent double-sided subduction or a crustal retro-wedge of one-sided subduction? The later structure could be formed in response to compression of the rigid arc crust. This project will acquire a detailed velocity structure of the crust and slab of the entire arc and the seismically active region of Puerto Rico and the Virgin Islands.

Terrestrial organic matter (OM) concentrations have been increasing in coastal waters, such as the Gulf of Maine (GoM), over the past 30 years. The implications of this change on critical mechanisms controlling the levels of mercury (Hg), and its toxic form, methylmercury (MeHg), in marine waters and at the base of the food web, are not well understood. Given this lack of knowledge, this proposal will examine the effects of climate-driven increases in terrestrial OM concentrations in GoM waters on the complex and often competing processes influencing: 1) Hg cycling and distribution; 2) the formation of MeHg; and 3) MeHg uptake to microplankton. Our central hypothesis is that higher terrestrial OM inputs and concomitant shifts in coastal OM concentration and quality will cause increases in Hg inputs, MeHg production and bioaccumulation. Terrestrial OM is thought to be a conduit for transfer of Hg from watersheds to coastal and offshore waters and controls the formation of aqueous MeHg by providing a microenvironment that supports bacterial Hg methylation. Increasing dissolved OM concentrations have been associated with decreased bioaccumulation of MeHg into phytoplankton, the primary bioaccumulation step for uptake of MeHg into seafood. However, our preliminary results show this association is mediated by OM source more than concentration, as indicated by the sulfur content of the OM. Furthermore, mixotrophic microplankton can bioaccumulate MeHg complexed with OM while feeding heterotrophically. Mixotrophs can seasonally dominate phytoplantkon assemblages in coastal waters, and the impact of heterotrophic feeding modes on MeHg uptake at the base of the food web has not been explored. This proposal is focused on studying the effects of OM dynamics on Hg and MeHg cycling and bioaccumulation through 1) field surveys and shipboard experiments in the GOM, where significant increases in terrestrially-sourced OM have caused a “yellowing” effect, and 2) through laboratory microcosm experiments using autotrophic and mixotrophic microplankton taxa under contrasting carbon acquisition modes and OM characteristics and concentrations. This work builds on our prior and ongoing work studying Hg cycling and bioaccumulation in estuarine environments along the Northeastern U.S. and will apply novel Hg and MeHg-specific isotopic analyses and measures of OM quality to enhance understanding. This research will fill important gaps in predicting the effects of environmental perturbations on marine MeHg levels, providing critical information to mitigating Hg emissions and MeHg exposures.

One of the longest open-ocean hydrographic stations in the world is maintained at the Hydrostation S site (formerly known as the Panulirus site) located ~25 km southeast of Bermuda in the North Atlantic Ocean. This program of repeat biweekly hydrographic observations began in 1954 (by Hank Stommel) and now, in its seventh decade, has proved to be the catalyst for numerous studies of ocean physics, biological processes and biogeochemistry. Hydrostation S continues to be recognized as one of the most important sustained ocean time–series. The renewal of the Hydrostation S program is proposed herein, extending this invaluable time–series of ocean hydrography to almost 70 years. The upper ocean warming trend has strengthened (about +1.4° C since the 1970's; ~+0.8°C in last decade) with significant salinification (+0.16). Deeper waters such as the Labrador Sea Water has cooled by a few tenths of a degree and freshened with a marked decadal oscillation. The signature of deoxygenation has been observed at Hydrostation S in the upper ocean (about 4 µmoles kg -1 decade -1 decrease in dissolved oxygen) as well as the oxygen minimum zone (~2.5 µmoles kg -1 decade -1 ). Hydrostation S also supports the longest global ocean CO 2 and acidification time-series (from 1983 to present) The major objective of the proposal is to continue Hydrostation S into the eighth decade with numerous questions related to warming and cooling, salinification and freshening, deoxygenation and insights on biogeochemical changes over time. This program constitutes frequent water column sampling of temperature, salinity, and dissolved oxygen (and indirectly, sampling of important ocean carbon time–series) of the North Atlantic subtropical gyre at the Hydrostation S site. Such work is complementary to other sustained observations such as the Bermuda Atlantic Time–series Study (BATS) and Ocean Flux Program (OFP). We propose to carry out a similar sampling format that has been followed for the past 68 years. As for the past ten years, we would continue to conduct two CTD profiles to better capture the deep–water variability while maintaining all the previous discrete depths. The first CTD cast will profile to full ocean depth (3,300–3,500 m) while the second CTD cast will profile to 500 m (to allow for instrumentation not rated for full ocean depth such as a PAR sensor). One indirect objective will be to continue to collaboratively evaluate a BIOS-based glider program with Hydrostation S data as critically important ground truthing data. The existing glider program has challenging issue, and the aim of this effort is to use robust and highly accurate Hydrostation S data to test the capability of emerging technologies over the next five to ten years.

One of the longest open-ocean hydrographic stations in the world is maintained at the Hydrostation S site (formerly known as the Panulirus site) located ~25 km southeast of Bermuda in the North Atlantic Ocean. This program of repeat biweekly hydrographic observations began in 1954 (by Hank Stommel) and now, in its seventh decade, has proved to be the catalyst for numerous studies of ocean physics, biological processes and biogeochemistry. Hydrostation S continues to be recognized as one of the most important sustained ocean time–series. The renewal of the Hydrostation S program is proposed herein, extending this invaluable time–series of ocean hydrography to almost 70 years. The upper ocean warming trend has strengthened (about +1.4° C since the 1970's; ~+0.8°C in last decade) with significant salinification (+0.16). Deeper waters such as the Labrador Sea Water has cooled by a few tenths of a degree and freshened with a marked decadal oscillation. The signature of deoxygenation has been observed at Hydrostation S in the upper ocean (about 4 µmoles kg -1 decade -1 decrease in dissolved oxygen) as well as the oxygen minimum zone (~2.5 µmoles kg -1 decade -1 ). Hydrostation S also supports the longest global ocean CO 2 and acidification time-series (from 1983 to present) The major objective of the proposal is to continue Hydrostation S into the eighth decade with numerous questions related to warming and cooling, salinification and freshening, deoxygenation and insights on biogeochemical changes over time. This program constitutes frequent water column sampling of temperature, salinity, and dissolved oxygen (and indirectly, sampling of important ocean carbon time–series) of the North Atlantic subtropical gyre at the Hydrostation S site. Such work is complementary to other sustained observations such as the Bermuda Atlantic Time–series Study (BATS) and Ocean Flux Program (OFP). We propose to carry out a similar sampling format that has been followed for the past 68 years. As for the past ten years, we would continue to conduct two CTD profiles to better capture the deep–water variability while maintaining all the previous discrete depths. The first CTD cast will profile to full ocean depth (3,300–3,500 m) while the second CTD cast will profile to 500 m (to allow for instrumentation not rated for full ocean depth such as a PAR sensor). One indirect objective will be to continue to collaboratively evaluate a BIOS-based glider program with Hydrostation S data as critically important ground truthing data. The existing glider program has challenging issue, and the aim of this effort is to use robust and highly accurate Hydrostation S data to test the capability of emerging technologies over the next five to ten years.

The 2019-2020 seismic swarm in southwestern Puerto Rico consisted of +13,000 earthquakes (M≥2.5) with 43 earthquakes with Mw ≥ 4.5 since its start on December 28, 2019. It was not a typical main shock with aftershocks diminishing in magnitude with time, but appeared to rupture a zone of diffuse deformation, where rupture may be transitioning from one fault to another (ten Brink et al., Tectonics, 2022). This activity may reflect the establishment of a new block boundary between Puerto Rico and Hispaniola, where Hispaniola is moving west relative to Puerto Rico. Most of the activity during this sequence occurred offshore, including the largest event, the Mw6.4 on January 7, 2020. The earthquake sequence caused extensive damage in coastal towns, co-seismic subsidence around Guayanilla Bay, liquefaction, ground failures, and the collapse of an iconic coastal rock bridge. The activity was centered around a defunct oil refinery and strategic facilities for the island, such as a liquid natural gas terminal, and an electric power station. The prolonged seismic activity had thus created anxiety among the island’s population. To better understand the seismic activity, the USGS carried out with logistical support by the University of Puerto Rico, a “rapid response” cruise on March 7-13, 2020, (just before the COVID lockdown) to map the faults. Logistical and environmental constraints necessitated the use of small sound source and receiving system. The only available boat was too small for the sea state and did not allow the collection of a dense seismic cruise at the desired line orientations. Although numerous faults were observed, line spacing was too sparse to determine the faults' geometry and their possible coalescence at depth. The goal of the proposed survey is to improve detection of the faults with depth and map their spatial connections and relationships by collecting a denser grid of seismic lines at the desired orientation aboard a larger ship, and by using GI guns and a longer streamer.

The California Current Ecosystem (CCE) Long-Term Ecological Research (LTER) site is a coastal upwelling biome and the site of a 73-year (ongoing) spatially-resolved ocean timeseries (CalCOFI) that has demonstrated physical forcing on multiple spatiotemporal scales with concomitant impacts on ocean biota. The CCE is part of the larger LTER Network, founded in 1980 by the National Science Foundation. CCE-LTER studies are making excellent progress towards diagnosing mechanisms of ecosystem change in a major upwelling ecosystem and developing a quantitative framework for forecasting future changes. Our field site is in the CA Current upwelling regime, centered around Point Conception, within the CalCOFI time series station plan. The CCE LTER field program includes several different elements: experimental process cruises, time series cruises (ship time augmented on existing CalCOFI cruises) and mooring servicing cruises to maintain the deep water CCE1 and CCE2 moorings. The science carried out on these field expeditions is highly interdisciplinary, involving elements of biological, chemical, and physical oceanography.

This is a class cruise to introduce graduate students in SIOB280 Biological Oceanography to sampling and organisms at sea. We will conduct CTD profiles, plankton net hauls, and an otter trawl, during two one-day cruises. The data will be used in class projects and exams.

Major infrastructure deployment and servicing cruise for the Pioneer Array of the National Science Foundation’s Ocean Observatories Initiative (OOI). The Pioneer Array includes a network of moorings and autonomous robotic vehicles to monitor waters of the continental shelf and slope south of New England and the shelf break front where nutrients and other properties are exchanged between the coast and the deep ocean. Data from the Pioneer Array will provide new insights into coastal ocean processes such as shelf/slope nutrient exchange, air-sea property exchange, carbon cycling, and ocean acidification that are important to the New England shelf, and to continental shelf ecosystems around the world. For further information, see http://www.oceanobservatories.org.

These cruises utilize funding provided by the University of Minnesota. Chief Scientists will be completing seed research cruises or using their ship time to take graduate and undergraduate students on the research vessel Blue Heron.

UW Oceanography Dept. Ocean 230 (and ESS 230) Student Cruise for Fall Quarter 2023.

In-Water Sentinels deployment of moorings

Annual survey using trawling and hydroacoustics to survey the health of the fisheries in Minnesota waters of Lake Superior

This project is a collaborative, multi-disciplinary study, with seasonal sampling in contrasting high and low productivity regions to quantify the role of diel vertically migratory (DVM) -mediated flux on C export and sequestration. This proposal uses unique technologies to directly sample day vs nighttime gravitational fluxes below the euphotic zone (EZ) and deep scattering layer (DSL), while also sampling the flux, particles, and geochemical gradients in between. These will be compared to the vertical distributions of migrator and resident zooplankton, analyzed both with new in-situ optical instruments and traditional nets to calculate active C flux. By sampling the fluxes timed to the daily migrations and their layering, we will be able to directly quantify their contribution to fecal pellet production in the EZ, as well as to export below the DSL. Together, this represents a comprehensive state of the art study for quantifying the role of DVM in the biological carbon pump (both active and passive fluxes).

Long-term observations over several decades are a powerful tool for investigating ocean physics, biology, and chemistry, and the response of the oceans to environmental change. The Bermuda Atlantic Time-Series Study, known as BATS, has been running continuously since 1988. The research goals of the BATS program are: (1) to improve our understanding of the time-varying components of the ocean carbon cycle and the cycles of related nutrient elements such as nitrogen, phosphorus, and silicon; and, (2) to identify the relevant physical, chemical and ecosystem properties responsible for this variability. In addition, the BATS program has strong and diverse broader impacts, contributing to the field of ocean sciences by providing high quality ocean observations and data for seagoing scientists and modelers, and a framework through which researchers can conceive and test hypotheses. This award will support the operations of the BATS program for five more years. The primary BATS research themes are as follows: (1) Quantify the role of ocean-atmosphere coupling and climate variability on air-sea exchange of CO2, and carbon export to the ocean interior; (2) Document trends and the controls on the interannual to decadal scale variability in carbon and nutrient cycles to their coupling in the surface and deep ocean via the Redfield Ratio paradigm; (3) Quantify the response of planktonic community structure and function, and impact on biogeochemical cycles to variability in surface fluxes and dynamical processes; (4) Facilitate development, calibration and validation of next generation oceanographic sensors, tools and technologies; and, (5) Generate a dataset that can be utilized by empiricists, modelers and students. This research integrates ocean physics, chemistry and biology into a framework for understanding oceanic processes and ocean change in the North Atlantic subtropical gyre. The existing 29 years of BATS data provide robust constraints on seasonal and interannual variability, the response of the Sargasso Sea ecosystem to natural climate variability, and signal detection of potential ocean changes. This project would extend the BATS program through years 31-35 to address a series of ten interlinked questions through integrated research approaches and a multitude of collaborative efforts. In addition to the themes above, and embedded into the ten questions and approaches, the BATS team will focus on, for example, coupling of particle production and biogeochemistry; revisiting the complexities of the biological carbon pump; oxygen decline; and changes in the hydrography, physics, ocean carbon cycle and biogeochemistry of the Sargasso Sea. The highest quality data observation and collection will be maintained and used to address these questions. Importantly, a wide range of collaborations at the BATS site, spanning the physical and biogeochemical disciplines, will aid these broad goals. Strong links to community stakeholders, and close collaboration (including methods intercomparisons and personnel exchanges) with the Hawaii Ocean Time-series are proposed. This work will extend the research findings of the project into educational and training opportunities within and beyond the oceanographic community, including training and mentorship of both undergraduate and graduate students.

One of the longest open-ocean hydrographic stations in the world is maintained at the Hydrostation S site (formerly known as the Panulirus site) located ~25 km southeast of Bermuda in the North Atlantic Ocean. This program of repeat biweekly hydrographic observations began in 1954 (by Hank Stommel) and now, in its seventh decade, has proved to be the catalyst for numerous studies of ocean physics, biological processes and biogeochemistry. Hydrostation S continues to be recognized as one of the most important sustained ocean time–series. The renewal of the Hydrostation S program is proposed herein, extending this invaluable time–series of ocean hydrography to almost 70 years. The upper ocean warming trend has strengthened (about +1.4° C since the 1970's; ~+0.8°C in last decade) with significant salinification (+0.16). Deeper waters such as the Labrador Sea Water has cooled by a few tenths of a degree and freshened with a marked decadal oscillation. The signature of deoxygenation has been observed at Hydrostation S in the upper ocean (about 4 µmoles kg -1 decade -1 decrease in dissolved oxygen) as well as the oxygen minimum zone (~2.5 µmoles kg -1 decade -1 ). Hydrostation S also supports the longest global ocean CO 2 and acidification time-series (from 1983 to present) The major objective of the proposal is to continue Hydrostation S into the eighth decade with numerous questions related to warming and cooling, salinification and freshening, deoxygenation and insights on biogeochemical changes over time. This program constitutes frequent water column sampling of temperature, salinity, and dissolved oxygen (and indirectly, sampling of important ocean carbon time–series) of the North Atlantic subtropical gyre at the Hydrostation S site. Such work is complementary to other sustained observations such as the Bermuda Atlantic Time–series Study (BATS) and Ocean Flux Program (OFP). We propose to carry out a similar sampling format that has been followed for the past 68 years. As for the past ten years, we would continue to conduct two CTD profiles to better capture the deep–water variability while maintaining all the previous discrete depths. The first CTD cast will profile to full ocean depth (3,300–3,500 m) while the second CTD cast will profile to 500 m (to allow for instrumentation not rated for full ocean depth such as a PAR sensor). One indirect objective will be to continue to collaboratively evaluate a BIOS-based glider program with Hydrostation S data as critically important ground truthing data. The existing glider program has challenging issue, and the aim of this effort is to use robust and highly accurate Hydrostation S data to test the capability of emerging technologies over the next five to ten years.

Characterizing Arctic ocean-ice-atmosphere variability and predicting the system’s evolution on synoptic to seasonal timescales requires observations that span a broad range of spatial and temporal scales. Forecast quality depends on observations for initialization, assimilation, and for informing how the simulations represent unresolved physics. Data intended for use in nowcast/forecast efforts must be delivered in a timely fashion - a challenging requirement for polar regions where ice blocks access to satellite services. To support Navy missions in the ice-covered Arctic, the Arctic Mobile Observing Innovative Naval Prototype (AMOS INP) is developing a mobile observing capability composed of ice-based Gateway Nodes and an array of complementary autonomous platforms (gliders, floats, AUVs), networked together through acoustic navigation and communication to enable coordinated, cooperative sampling and efficient data relay.

UW Oceanography Dept. Ocean Memory Workshop

UW Oceanography Dept. Ocean 492 Research Apprentices Student Cruise for Fall Quarter 2023.

We plan to conduct depth-discrete midwater trawls using a 10m2-MOCNESS to collect a diversity of micronekton animals from across epipelagic, mesopelagic, and upper bathypelagic depths spanning the continental shelf into offshore waters within the southern California Current Ecosystem. CTD casts will also be conducted at each of the stations.