Research

The Labrador Coastal Current (LCC) transports fresh outflow from the Canadian Arctic Archipelago, Hudson Bay, and the Greenland Ice Sheet southward along the Newfoundland and Labrador Shelf. If mixed offshore into the boundary current of the subpolar gyre, the fresh water in the LCC has the potential to stratify the upper ocean and alter the Atlantic Meridional Overturning Circulation (AMOC). Yet very little is currently known about the transport of the LCC and whether the LCC interacts with the large-scale North Atlantic circulation, or remains on the shelf around the Grand Banks. This project would study the fate of the LCC and its transport along the Canadian Labrador and Newfoundland coastlines. Using a combined Eulerian and Lagrangian observational study, the project would examine whether the fresh, buoyant water in the LCC moves off the shelf to join the Labrador Current, hypothetically due to a combination of the region’s complex bathymetry and strong wind forcing. The work would support an early career researcher, provide project material for a summer undergraduate intern, and involve 7 students with cruise experience as watch standers. Four moorings will be deployed in summer for one year, along the Canadian Atlantic Zone Monitoring Program (AZMP) Seal Island hydrographic section inshore of Hamilton Bank, which will provide the first continuous volume and freshwater transport time series of the LCC. In addition, 46 surface drifters will be released into the LCC, in subsets at 15 day intervals, by three moored Submerged Autonomous Launch Platforms (SALPs). Two cruises will be conducted along the deployment and recovery efforts, collection high-resolution shipboard ADCP and CTD surveys of the Newfoundland and Labrador Shelf. Together with the historical AZMP hydrographic sections, the project will quantify transport and track the pathways and fate of the fresh water in the LCC, and will identify hot spots of shelf-basin exchange. Timing of the NASA Surface Water and Ocean Topography (SWOT) satellite launch and three-month “Fast- Sampling Phase” with daily flyovers may coincide with the drifter releases, and would provide high-resolution sea-surface height (SSH) and surface geostrophic velocities of the inner shelf, potentially broadening the spatial and temporal extent of this targeted study.

Oceans, estuaries and coastal habitats are changing quickly, driven by both natural processes and human activities. The Washington Ocean Acidification Center (WOAC) was established by the state legislature to advance research and monitoring of ocean acidification and its biological effects in Washington waters. One facet of that research is the WOAC cruises. We go out three times a year, April, July, and September, to monitor ocean acidification and its affect on biology. These cruises are part of a long term time Ocean Acidification time series.

AOML SFP regional surveys over the southwest Florida shelf and the Florida Keys reef tract have been routinely performed via the University of Miami's R/V F. G. Walton Smith on a bimonthly basis. Sampling methodologies similar to those utilized on AOML SFP bay surveys (discrete sampling and flow-through measurements) have been employed on these regional research cruises.

We will be conducting sediment coring and hydrocast surveys, and running experiments using radioisotope on the Louisiana Shelf in late summer/fall 2024 and spring 2025.

Researchers from NOAA's Atlantic Oceanographic and Meteorological Laboratory (AOML) in Miami, FL, conduct regular bimonthly hydrographic surveys at 27N in the Florida Straits to monitor the transport and water-mass properties of the Florida Current. The Florida Current is part of the Gulf Stream system, which is the upper limb of the western boundary current system in the North Atlantic Ocean. These cruises are a part of the laboratory’s long-running Western Boundary Time Series (WBTS) project and directly measure the Florida Current at nine locations across the Straits of Florida at 27N, between Jupiter, Florida, and the Little Bahama Bank in the Bahamas. WBTS 27N hydrographic sections, conducted bimonthly throughout the year, are critical to improving our understanding of the North Atlantic Subtropical Gyre circulation and the Atlantic Meridional Overturning Circulation (AMOC). Importantly, data collected during these cruises and others are also used to calibrate the 27N submarine cable system which publicly provides daily transport estimates of the Florida Current . The AMOC is a significant factor in climate change, oceanic carbon sequestration, and sustainable fisheries. In addition to the direct ship-based measurements conducted during WBTS 27N cruises, these surveys also support and service project moored instrumentation, located on either side of the Straits, which provide key times series data. These monitoring efforts are necessary for quantifying AMOC and gyre variability over time and for identifying decadal changes in the large-scale circulation, water-mass properties, and heat transport. The WBTS project is part of an international collaboration which partners include AOML’s WBTS, the University of Miami’s Rosenstiel School of Marine and Atmospheric Science (UM/RSMAS) Meridional Overturning Circulation and Heat-flux Array (MOCHA) Program, and the UK National Oceanography Centre’s Rapid Climate Change (RAPID) Program.

The ONR-funded Task Force Ocean: New England Seamounts 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 ship-time request involves 2 PIs on this effort who focus on geacoustic inversion in deep water with complex seamount topography and acoustic scattering characterization of the biology and physics at the New England 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. On the other hand, the steep 3D topography and corrugated basalt seafloor will also impact low-frequency acoustic propagation. In particular, one expects acoustic scattering, diffraction and shadowing created by the seamounts. Those will create heavy 3D propagation effects, which are affected not only by the bathymetry, but also by the geoacoustic properties of the sub-bottom. The importance of seafloor geoacoustic properties to understand and predict acoustic propagation over seamounts has been emphasized during the 2004 ONR Basin Acoustic Seamount Scattering Experiment (BASSEX), but their experimental estimation stays an open question. 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 (geological, physical and biological) 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. A coordinated seamount acoustic experiment will be conducted involving high resolution, synoptic measurements of physical and biological processes using a combination of shipboard broadband backscatter, CTD and ADCP measurements, AUV-based sonar and oceanographic measurements, a novel towed vehicle with broadband split-beam arrays spanning 1-450 kHz (Deep-See), a towed low-frequency acoustic source (J15-3), a towed airgun (Sercel GI-210) and a moored Biosonar for long time scale observations of DSLs. A thorough mapping of the DSL and flank and summit fish populations is proposed, as well as determination of the dominant physical oceanographic processes that drive distribution and abundance of acoustically important fish species. Further, low-frequency acoustic mapping of the Atlantis II seamount flank will be performed using the airgun and long-range 3D acoustic propagation experiments will be performed using the J15-3 source (those will rely on acoustic receiver mooring experiments deployed during a previous cruise).

Our study will use cutting-edge in situ imaging (using a UVP-DEEP) of Rhizaria to bypass limitations in other sampling methods and to produce accurate estimates of Rhizaria biomass. Additionally, sampling will occur across a wide depth range (0-1200 m), at monthly intervals, and in conjunction with a wide array of other biological, chemical, and physical oceanographic measurements (as part of the Bermuda Atlantic Time-series Study, BATS). UVP imagery data will be integrated with molecular identification of Rhizaria using community metabarcoding and barcoding of individual Rhizaria collected from MOCNESS net tows taken in conjunction with UVP casts. Size-specific elemental analyses of Rhizaria and seasonally and vertically explicit estimates of Rhizaria biomass will be used to model their contributions to vertical flux in the system.

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.

SEFIS is a fishery-independent research group that surveys reef fish using traps and video from Cape Hatteras, NC, to St. Lucie Inlet, FL, from 15-115 m deep.

This study will collect temperature measurements in seafloor sediments offshore Washington and Oregon, and map the distribution of those sediments, to understand the controls on temperatures in the system and improve estimates of subduction zone temperatures. The results of this research have direct societal benefit, by informing earthquake hazard estimates. In addition, the proposed project will enhance education at New Mexico Tech, a STEM-focused Hispanic-serving institution. Two graduate students will be trained in geophysics and hydrogeology. Results of the project will be incorporated into ?using data in the classroom? efforts, improving hands-on experience in undergraduate courses.

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, the Hawaii Ocean Time-series (HOT) program, near Hawaii was established. For over 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.

NES-LTER cross-shelf transect cruises are conducted between Martha’s Vineyard and the continental shelf break directly south. The overarching goal of the NES-LTER is to understand and predict how planktonic food webs change through space and time in response to changes in the physical environment, and how those changes impact ecosystem productivity, including of higher trophic levels. Observations and models are focused on processes and mechanisms that structure pelagic food webs, trophic transformations, and productivity, as well as the key interactions and feedbacks that modulate relationships among them. NES-LTER transect process cruises are focused on characterizing cross-shelf distributions of physical properties, nutrients, production rates, and plankton. Approximately 11 stations will be occupied in waters depths typically less than 200 m, but up to ~1600 m. Operations will include underway sampling of biological and chemical properties with science-provided instruments, CTD/rosette casts, net tows, on-deck incubations, and deployment of a towed vehicle.

Air-sea exchange is the major source for, and sink for, ocean mercury (Hg) although the details of these processes are still poorly understood. The proposed research is designed to extend and enhance observations made in the North Atlantic on prior cruises as well as reinforce findings from the studies under GEOTRACES in the Pacific and Arctic Oceans. The techniques to be used on the cruises have been refined on these prior endeavors. The research project is aimed at measuring the air-sea exchange of mercury in the ocean and atmosphere in and around Bermuda. Samples will also be collected at the Bermuda atmospheric station and on the research cruises on the RV Atlantic Explorer. Some equipment will also be deployed on the regular BATS cruises on the Atlantic Explorer but these are not part of the current request. The support of BIOS has been obtained to enable the collections at the atmospheric station and for the sampling on the BATS cruises and these are not part of the current request. Samples will eb collected in air and water continuously while the ship is moving as well as at specific stations where the upper water column will eb sampled. it is expected that the majority of teh time will eb spent with the ship underway.

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.

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 MERCI cruises are multi-mission expeditions co-sponsored by both the Coral Propagation Techniques (CPT) as well as Habitat Assessment and Evaluation (HAE) projects to support coral propagation activities as well as documenting and mesophotic and deep benthic communities and habitats under the Mesophotic and Deep Benthic Communities portfolio (MDBC). MERCI (Mesophotic Expeditions for the Restoration of Coral and other Invertebrates) missions began in 2022 to support coral husbandry and propagation as well as habitat and community assessment in reference areas not affected by the Deepwater Horizon Oil spill. Thus far, the expeditions have been conducted in and around the Flower Gardens National Marine Sanctuary (FGBNMS) West of the Mississippi River. The MERCI-4 expedition will follow upon MERCI-1,2 and 3, working in the mesophotic depth zone (50 - 400 m) of the northwestern Gulf of Mexico with an observation-class ROV. The vehicle will conduct exploratory transects, building on knowledge in and around the FGBNMS expansion area. The ROV will collect coral samples for live aquaria, coral husbandry, reproduction, genetic, and microbiome studies.

This study will examine nitrogen cycling, community composition, and the nitrogen isotopic composition of chloropigments to evaluate cyanobacterial productivity in modern and recent aquatic systems. The nitrogen isotope composition of chloropigments may provide a powerful proxy for understanding primary productivity and the relative importance of cyanobacteria to export production and nitrogen cycling. Such a proxy would be valuable not only for management of modern systems but has significant implications for increasing our understanding of the role of cyanobacteria throughout Earth history. Here we will test these molecular isotopic proxies in contemporary aquatic ecosystems to assess their efficacy for: 1) determining the relative contributions of cyanobacteria vs eukaryotic algae (e.g. diatoms) to primary production, 2) evaluating export production of cyanobacterial productivity (including blooms), and 3) constraining historical cyanobacteria productivity in the sedimentary record. We propose to investigate the impact of export production on nitrogen cycling (N recycling vs. removal rates) using a combination of water column and sediment incubations and the molecular isotopic composition of porphyrins from both suspended particulate matter and sinking particulate material in modern lake systems (Lakes Superior and Erie). We will compare a system characterized by eutrophication and seasonal cyanobacterial blooms (Lake Erie) with one characterized by significant picocyanobacteria productivity but the near-absence of cyanobacterial blooms (Lake Superior). Finally, we will investigate the paleorecord of cyanobacterial activity using sediment cores spanning the past several hundred years to evaluate the system prior to human impact relative to the present condition.

The purpose of this campaign is to deploy four metocean moorings at various locations in the western Gulf of Mexico. General distance from LUMCON is approximately 200 nm. The moorings are taut and relatively short, ranging in length from 12 m to 90 m long. Approximate water depth for the area is 1200-1300 m. Moorings will measure subsea near bed currents.

This project will be conducted to support 5 days of testing of the ZRay vehicle. The vehicle will be run through a variety of speed and depth profiles while using the Sproul as the launch and recovery ship.

The project will test key hypotheses about deep-sea methane dynamics including determining if there are significant lags in microbial responses after exposure to elevated methane concentrations, determining the relationships of AMOR to methane and DIN concentrations and investigating the response times and magnitude of methanotrophs to spatial and temporal variability in methane concentration. Successful collection of in situ AMOR and associated microbial community data will prove important for modeling ocean methane dynamics over a range of oceanographic conditions including seep-enriched bottom waters and accidental hydrocarbon releases.

We seek support for early career scientists (up to 12 in total) to acquire the necessary leadership, planning, and practical skills and experience required to lead an oceanographic research cruise focused on biological and chemical oceanography in conjunction with the Hawaii Ocean Time-series. The proposal has three major objectives: 1) provide early career researchers with experience and training in cruise leadership and execution, 2) introduce cruise participants to oceanographic sampling equipment and training on the collection of biological and chemical oceanographic samples, and 3) obtain high-quality measurements to inform a broad understanding of microbial diversity and rates of particle production and flux in the North Pacific Subtropical Gyre (NPSG). The project will be highlighted by a 5-day research cruise to Station ALOHA in the subtropical North Pacific Ocean.

Organism aggregation, resource patchiness, and layering have long been recognized as fundamental ecosystem properties, especially in dynamic marine pelagic systems. However, integrating fine-scale (1-10 m) water column structure into our understanding of the forces that regulate marine ecosystems has proved challenging. Specifically, an overwhelming majority of marine organisms (plankton) experience their environment at fine spatial scales, which are difficult to sample, yet most measurements of chemical and biological parameters that define the structure of food webs and the flow of energy are averaged over much larger portions of the water column. This mismatch hinders our ability to understand the trophic consequences of fine-scale variability. Addressing this challenge will help to resolve key, and potentially predictable, sequences of events that change community structure and have trophic consequences that propagate throughout the food web in productive continental shelf environments. The trophic consequences of layers and patches depends on the proliferation of the zooplankton groups that exploit them. Conversely, other groups may proliferate in environments lacking vertical structure. One key trophic link on continental shelves is occupied by grazers such as doliolids and copepods – the relative abundance of these groups can determine if carbon is vertically exported or recycled within the microbial loop. Our long-term goals are to understand the ecological role of doliolids and the conditions that favor their proliferation (compared to copepods and other crustaceans). Because doliolids aggregate on fine spatial scales in several ecosystems, biological measurements need to be made on similar spatial scales and through time. Obtaining these measurements within different oceanographic contexts can answer several fundamental questions. For example, what are the trophic consequences of fine scale structure? Do these structures favor particular zooplankton communities above and below, and over what temporal and spatial scales do these structures persist or extend? Answering these questions requires sampling with complementary techniques, and will advance the fundamental understanding of how ecosystems will respond to changes in oceanographic structure, placing seemingly chaotic zooplankton communities into a predictive framework. We propose an ambitious field campaign in two shelf ecosystems with similar zooplankton taxa yet contrasting oceanographic regimes where doliolids are known to form blooms. The sampling will encompass two seasons (summer and winter) with contrasting degrees of stratification. Innovative molecular and stable-isotope measurements will allow for a robust coupling to oceanographic features and zooplankton abundance and community composition, elucidating the trophic consequences of vertical structure, layering, and mixing. In addition to primary research cruises, the multi-cruise plan will also include cruises that will be focused on optimizing the use of novel and proto-type equipment (sea trials) and several education cruises for graduate students and K-12 educators.

This project will maintain a high-resolution mooring array to quantitatively measure, for the first time, what appears to be the main conduit of dense water feeding the Faroe Bank Channel overflow. Accompanying shipboard surveys will trace the flow upstream to its source region(s), and also document its downstream evolution to where it overflows in the Faroe Bank Channel. We will augment the observations with modeling and simple theory to provide dynamical context. The work is part of a larger international program to address the pathways and mechanisms by which dense water is supplied to the eastern Greenland-Scotland Ridge, through coordinated observations and modeling. Researchers from seven institutions comprise the team, each bringing considerable resources and expertise. Together, this will fundamentally advance our understanding of this important component of the AMOC. The name of the collaborative program is “Upstream Pathways of the Faroe Overflow” (UFO).

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, the Hawaii Ocean Time-series (HOT) program, near Hawaii was established. For over 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.

This cruise will focus on equipment testing of marine robot systems, cooperative autonomy algorithms, and communication across heterogeneous networks and platforms.