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Statistical models built using different data sources and methods can exhibit conflicting patterns. We used the northern stock of black sea bass (Centropristis striata) as a case study to assess the impacts of using different fisheries data sources and laboratory‐derived physiological metrics in the development of thermal habitat models for marine fishes. We constructed thermal habitat models using generalized additive models (GAMs) based on various fisheries datasets as input, including the NOAA Northeast Fisheries Science Center (NEFSC) bottom trawl surveys, various inshore fisheries‐independent trawl surveys (state waters), NEFSC fisheries‐dependent observer data, and laboratory‐based physiological metrics. We compared each model's GAM response curve and coupled them to historical ocean conditions in the U.S. Northeast Shelf using bias‐corrected ocean temperature output from a regional ocean model. Thermal habitat models based on shelf‐wide data (NEFSC fisheries‐dependent observer data and fisheries‐independent spring and fall surveys) explained the most variation in black sea bass presence/absence data at ~15% deviance explained. Models based on a narrower range of sampled thermal habitat from inshore survey data in the Northeast Area Monitoring and Assessment Program (NEAMAP) and the geographically isolated Long Island Sound data performed poorly. All models had similar lower thermal limits around 8.5℃, but thermal optima, when present, ranged from 16.7 to 24.8℃. The GAMs could reliably predict habitat from years excluded from model training, but due to strong seasonal temperature fluctuations in the region, could not be used to predict habitat in seasons excluded from training. We conclude that survey data source can greatly impact development and interpretation of thermal habitat models for marine fishes. We suggest that model development be based on data sources that sample the widest range of ocean temperature and physical habitat throughout multiple seasons when possible, and encourage thorough consideration of how data gaps may influence model uncertainty., This study assesses the sensitivity of generalized additive models, frequently used in habitat modeling, to various fisheries data sources used as input by using black sea bass (Centropristis striata) as a case study. Results show that similarities and differences between habitat models can inform uncertainty estimates and can have strong implications for coupled oceanographic habitat models often used to represent spatial habitat distributions for a wide variety of applications.

The U.S. East Coast has 1.7 million acres of federal bottom under lease for the development of wind energy installations, with plans for more than 1,500 foundations to be placed. The scale of these wind farms has the potential to alter the unique and delicate oceanographic conditions along the expansive Atlantic continental shelf, a region characterized by a strong seasonal thermocline that overlies cold bottom water, known as the “Cold Pool.” Strong seasonal stratification traps cold (typically less than 10°C) water above the ocean bottom sustaining a boreal fauna that represents vast fisheries, including the most lucrative shellfish fisheries in the United States. This paper reviews the existing literature and research pertaining to the ways in which offshore wind farms may alter processes that establish, maintain, and degrade stratification associated with the Cold Pool through vertical mixing in this seasonally dynamic system. Changes in stratification could have important consequences in Cold Pool setup and degradation, processes fundamental to high fishery productivity of the region. The potential for these multiple wind energy arrays to alter oceanographic processes and the biological systems that rely on them is possible; however, a great deal of uncertainty remains about the nature and scale of these interactions. Research should be prioritized that identifies stratification thresholds of influence, below which turbines and wind farm arrays may alter oceanographic processes. These should be examined within context of spatial and seasonal dynamics of the Cold Pool and offshore wind lease areas to identify potential areas of further study.

Palmer Deep Canyon is one of the biological hotspots associated with deep bathymetric features along the Western Antarctic Peninsula. The upwelling of nutrient-rich Upper Circumpolar Deep Water to ...

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During summer, distinctive, bottom-trapped, cold water mass of remnant local and remote winter water called Cold Pool Water (CPW) resides as a swath over the mid to outer continental shelf throughout much of the Middle Atlantic Bight (MAB). This evolving CPW is important because it strongly influences the ecosystem, including several important fisheries. Thus, there is a priority to better understand the relevant ocean processes and develop CPW forecast capability. Over the past decade, repeated high-resolution Slocum glider measurements of ocean water properties along a New Jersey cross-shelf transect have helped to define the variability of the CPW structure off New Jersey. More recently the Mid-Atlantic Regional Association Coastal Ocean Observing System-supported ocean gliders have occupied a series of along-shelf zigzag trajectories from Massachusetts to New Jersey and New Jersey to Maryland. The comprehensive set of March through November 2007 glider measurements has been used to define the annual evolution of the 10oC Cold Pool in terms of its distribution and water properties. Here we highlight July through October 2007 general warming and salting of the Cold Pool at rates of approximately 1oC per month and 0.06 psu per month. The nominal 100m lateral resolution of the glider measurements enabled us to define the footprint of the 10oC Cold Pool. Assuming a 30m upper layer depth, we estimated Cold Pool volumes varying from 4099 km3 in summer 2007 to 2391 km3 in autumn 2007.

Biological hotspots along the West Antarctic Peninsula (WAP) are characterized by high phytoplankton productivity and biomass as well as spatially focused penguin foraging activity. While unique physical concentrating processes were identified in one of these hotspots, understanding the mechanisms driving the blooms at these locations is of high importance. Factors posited to explain the blooms include the upwelling of macronutrient‐ and micronutrient‐enriched modified Upper Circumpolar Deep Water (mUCDW) and the depth of the mixed layer influencing overall light availability for phytoplankton. Using shipboard trace‐metal clean incubation experiments in three different coastal biological hotspots spanning a north‐south gradient along the WAP, we tested the Canyon Hypothesis (upwelling) for enhanced phytoplankton growth. Diatoms dominated the Southern region, while the Northern region was characterized by a combination of diatoms and cryptophytes. There was ample concentration of macronutrients at the surface and no phytoplankton growth response was detected with the addition of nutrient‐enriched mUCDW water or iron solution to surface waters. For all treatments, addition of mUCDW showed no enhancement in phytoplankton growth, suggesting that local upwelling of nutrient‐enriched deep water in these hotspots was not the main driver of high phytoplankton biomass. Furthermore, the dynamics in the photoprotective pigments were consistent with the light levels used during these incubations showing that phytoplankton are able to photoacclimate rapidly to higher irradiances and that in situ cells are low light adapted. Light availability appears to be the critical variable for the development of hotspot phytoplankton blooms, which in turn supports the highly productive regional food web.

This chapter discusses the opportunities enabled by leveraging ocean observation and prediction in an emerging sector of the new blue economy. As a foundational component of our economy, the fishing industry is poised to codevelop observational and predictive tools that support new products and services that can be operationalized and commercialized as part of a new blue economy. We present two case studies as examples of how seascape ecology and ocean observing can support a new class of fisheries products and services. These products and services can serve the fishing and regulatory sector with various forms of dynamic habitat classification, and through community based codevelopment, the economic benefit of these products can be rapidly delivered in a way that is impactful and informative to all the economies linked to commercial and recreational fishing.

A decade (2007–2016) of hourly 6-km-resolution maps of the surface currents across the Mid-Atlantic Bight (MAB) generated by a regional-scale High Frequency Radar network are used to reveal new insights into the spatial patterns of the annual and seasonal mean surface flows. Across the 10-year time series, temporal means and interannual and intra-annual variability are used to quantify the variability of spatial surface current patterns. The 10-year annual mean surface flows are weaker and mostly cross-shelf near the coast, increasing in speed and rotating to more alongshore directions near the shelfbreak, and increasing in speed and rotating to flow off-shelf in the southern MAB. The annual mean surface current pattern is relatively stable year to year compared to the hourly variations within a year. The 10-year seasonal means exhibit similar current patterns, with winter and summer more cross-shore while spring and fall transitions are more alongshore. Fall and winter mean speeds are larger and correspond to when mean winds are stronger and cross-shore. Summer mean currents are weakest and correspond to a time when the mean wind opposes the alongshore flow. Again, intra-annual variability is much greater than interannual, with the fall season exhibiting the most interseasonal variability in the surface current patterns. The extreme fall seasons of 2009 and 2011 are related to extremes in the wind and river discharge events caused by different persistent synoptic meteorological conditions, resulting in more or less rapid fall transitions from stratified summer to well-mixed winter conditions.

There are several different types of floatables in the ocean. Some of these floating particles or drifters are of high value to people and are worth using resources to track and recover, such as people, boats, or equipment. To recover a drifting particle, the rescue party would need to have some information on where the particle may be located and where it may be headed. Lots of effort in the oceanography world in recent years has gone into providing the kind of data that is invaluable for such a task. There are many ocean and atmospheric models well suited to specific regions, as well as oceanography equipment reporting data that are translated and recorded in a format people can use. Several of these data are now freely available online, and easy to access. We test HF Radar and the regional ocean model Doppio to track a surface drifter and a glider in distress using the particle tracking framework OpenDrift. We found that HFR and Doppio do have some differences in trajectories but mostly agree in the 48-hour simulations. The tools used in this analysis are open source, and a collection of scripts is being made available for interested parties.

CONVERGE, with National Science Foundation support, was a fully integrated scientific and broader impact program focused on a biological hotspot along the Western Antarctic Peninsula. The objective of our approach was to connect field-deployed Science Teams and our target audiences, middle and high school educators and students, through real-world data to elevate our audiences' experience from science aware spectator to working scientist. Based on experience gained from prior work and a documented need to elevate the student experience in science, we applied a multitiered program that integrated existing methods of known success (educator professional development, daily Expedition Diary blogs, live videoconferences between the deployed Science Team and classrooms back in the United States) with new tools that enabled our student audience to participate in and conduct their own peer-reviewed science (data primers, proposal review, and a science symposium). Through a comprehensive evaluation program, educators reported a change in their teaching practice to increase students' data collection and analytical skills and provided more opportunities to authentically emulate the process of science and better understand the impacts of climate change in this Antarctic ecosystem. Additionally, the educators and students both reported personal connections to the data, which motivated the students to push their comfort zones when analyzing real-time data.

This study applied a Spike-Filter (SF) method to identify and remove rapidly moving clouds over the coastal ocean in GOES-16 satellite sea surface temperature fields (SST). These images were then gap-filled to capture upwelling in the Mid Atlantic Bight (MAB), a critical process that impacts ecosystems and atmospheric processes in the region and is important to coastal regions around the world. During the 2019 upwelling season, the default Quality Filter (QF) provided to identify and remove clouds from GOES SST consistently removed upwelling pixels, resulting in ~15% MAB coastal SST coverage. The Spike Filter (SF) method increased MAB coastal SST coverage to 30% and maintained overall accuracy. GOES SF DINEOF SST approximately doubled the number of detected upwelling days compared to MUR SST. The longest upwelling event detected in GOES SF DINEOF persisted for over 17 days, which is longer than upwelling events previously observed in the MAB (Glenn et al., 2004).This suggests that the MAB can have persistent, rather than episodic upwelling as previously thought. Clear detection of the timing and duration of upwelling events is important as it provides estimates for ecological and physical responses in the MAB and coastal regions around the world. GOES-16 SST has the potential to improve upwelling detection and should be further studied for application in ocean and atmospheric modeling.

Antarctic krill, Euphausia superba , is a highly abundant and ecologically important zooplankton species in the Southern Ocean. Regions of elevated Antarctic krill biomass exist around Antarctica, often as a result of the concentrating effect of bathymetry and ocean currents. Such areas are considered biological hotspots and are key foraging grounds for numerous top predators in the region. A hotspot of Antarctic krill biomass exists off the southern extent of Anvers Island, Western Antarctic Peninsula, and supports a population of Adelie penguins that feed almost exclusively on it, as well as numerous other top predators. We investigated the spatio-temporal variability in Antarctic krill biomass and aggregation structure over four consecutive summer seasons, identifying environmental factors that were responsible. We identified three distinct krill aggregation types (Large-dense, Small-close and Small-sparse), and found that the relative proportion of each type to total aggregation numbers varied significantly between survey days. Large-dense aggregations occurred more frequently when westerly winds predominated and when the local mixed tide was in the diurnal regime. Small-close aggregations were also more frequent during diurnal tides and were negatively correlated with phytoplankton biomass. Small-sparse aggregations, on the other hand, were more prevalent when the mixed tide was in the semi-diurnal phase. We suggest that, under certain conditions (i.e. diurnal tides and westerly winds), the biological hotspot in the nearshore waters off Palmer Station, Anvers Island, functions as a zone of accumulation, concentrating krill biomass. Our findings provide important information on the dynamics of Antarctic krill at the local scale.

We use autonomous underwater vehicles to characterize the spatial distribution of Upper Circumpolar Deep Water (UCDW) on the continental shelf of the West Antarctic Peninsula (WAP) and present the first near-synoptic measurements of mesoscale features (eddies) containing UCDW on the WAP. Thirty-three subsurface eddies with widths on the order of 10 km were detected during four glider deployments. Each eddy contributed an average of 5.8 x 1016 J to the sub-pycnocline waters, where a cross-shelf heat flux of 1.37 x 1019 J yr−1 is required to balance the diffusive loss of heat to overlying winter water and to the near-coastal waters. Approximately two-thirds of the heat coming onto the shelf diffuses across the pycnocline and one-third diffuses to the coastal waters; long-term warming of the sub-pycnocline waters is a small residual of this balance. Sixty percent of the profiles that contained UCDW were part of a coherent eddy. Between 20 and 53% of the lateral onshore heat flux to the WAP can be attributed to eddies entering Marguerite Trough, a feature in the southern part of the shelf which is known to be an important conduit for UCDW. A northern trough is identified as additional important location for eddy intrusion.

Background Acoustic biotelemetry sensors have been fully integrated into a broad range of mobile autonomous platforms; however, estimates of detection efficiency in different environmental conditions are rare. Here, we examined the role of environmental and vehicle factors influencing detection range for two common acoustic receivers, the VEMCO mobile transceiver (VMT) and a VEMCO cabled receiver (VR2c) aboard a Teledyne Slocum glider. We used two gliders, one as a mobile transmitting glider and one as a mobile receiving glider during the fall in the mid-Atlantic coastal region. Results We found distance between gliders, water depth, and wind speed were the most important factors influencing the detection efficiency of the VMT and the VR2c receivers. Vehicle attitude and orientation had minimal impacts on detection efficiency for both the VMT and VR2c receivers, suggesting that the flight characteristics of the Slocum glider do not inhibit the detection efficiency of these systems. The distance for 20% detection efficiency was approximately 0.4 and 0.6 km for the VMT and VR2c, respectively. The VR2c receivers had significantly lower detection efficiencies than the VMT receiver at distances 0.1 km. Conclusions Slocum gliders are effective biotelemetry assets that serve as sentinels along important animal migration corridors. These gliders can help elucidate the relationships between telemetered organisms and in situ habitat. Therefore, estimating the detection ranges of these common telemetry instruments provides an important metric for understanding the spatial scales appropriate for habitat selection inferences.

Large uncertainty in the predicted intensity of tropical cyclones (TCs) persists compared to the steadily improving skill in the predicted TC tracks. This intensity uncertainty has its most significant implications in the coastal zone, where TC impacts to populated shorelines are greatest. Recent studies have demonstrated that rapid ahead-of-eye-center cooling of a stratified coastal ocean can have a significant impact on hurricane intensity forecasts. Using observation-validated, high-resolution ocean modeling, the stratified coastal ocean cooling processes observed in two U.S. Mid-Atlantic hurricanes were investigated: Hurricane Irene (2011)—with an inshore Mid-Atlantic Bight (MAB) track during the late summer stratified coastal ocean season—and Tropical Storm Barry (2007)—with an offshore track during early summer. For both storms, the critical ahead-of-eye-center depth-averaged force balance across the entire MAB shelf included an onshore wind stress balanced by an offshore pressure gradient. This resulted in onshore surface currents opposing offshore bottom currents that enhanced surface to bottom current shear and turbulent mixing across the thermocline, resulting in the rapid cooling of the surface layer ahead-of-eye-center. Because the same baroclinic and mixing processes occurred for two storms on opposite ends of the track and seasonal stratification envelope, the response appears robust. It will be critical to forecast these processes and their implications for a wide range of future storms using realistic 3D coupled atmosphere-ocean models to lower the uncertainty in predictions of TC intensities and impacts and enable coastal populations to better respond to increasing rapid intensification threats in an era of rising sea levels.

Multi-year satellite records indicate an asymmetric spatial pattern in the summer bloom in the Northern Ross Sea, with the largest blooms over the shallows of Pennell Bank compared to Mawson Bank. In 2010–2011, high-resolution spatiotemporal in situ sampling focused on these two banks to better understand factors contributing to this pattern. Dissolved and particulate Fe profiles suggested similar surface water depletion of dissolved Fe on both banks. The surface sediments and velocity observations indicate a more energetic water column over Mawson Bank. Consequently, the surface mixed layer over Pennell Bank was more homogeneous and shallower. Over Mawson Bank we observed a thicker more homogeneous bottom boundary layer resulting from stronger tidal and sub-tidal currents. These stronger currents scour the seafloor resulting in sediments less likely to release additional sedimentary iron. Estimates of the quantum yield of photosynthesis and the initial slope of the photosynthesis-irradiance response were lower over Mawson Bank, indicating higher iron stress over Mawson Bank. Overall, the apparent additional sedimentary source of iron to, and longer surface residence time over Pennell Bank, as well as the reduced fluxes from the more isolated bottom mixed layer over Mawson Bank, sustain the observed asymmetric pattern across both banks.

The OceanGliders program started in 2016 to support active coordination and enhancement of global glider activity. OceanGliders contributes to the international efforts of the Global Ocean Observation System (GOOS) for Climate, Ocean Health, and Operational Services. It brings together marine scientists and engineers operating gliders around the world: (1) to observe the long-term physical, biogeochemical, and biological ocean processes and phenomena that are relevant for societal applications; and, (2) to contribute to the GOOS through real-time and delayed mode data dissemination. The OceanGliders program is distributed across national and regional observing systems and significantly contributes to integrated, multi-scale and multi-platform sampling strategies. OceanGliders shares best practices, requirements, and scientific knowledge needed for glider operations, data collection and analysis. It also monitors global glider activity and supports the dissemination of glider data through regional and global databases, in real-time and delayed modes, facilitating data access to the wider community. OceanGliders currently supports national, regional and global initiatives to maintain and expand the capabilities and application of gliders to meet key global challenges such as improved measurement of ocean boundary currents, water transformation and storm forecast.

The physical mechanisms that maintain and deliver phytoplankton and Antarctic krill biomass, potentially increasing prey availability to predators, are not well known. The short surface ocean residence times of 1-2 days over Palmer Deep is in conflict with the prevailing hypotheses that local growth support phytoplankton at the base of the food web in these biological hotspots. Instead, the implication is that horizontal dynamics are likely more important to maintaining these biological hotspots than local upwelling. However, coincident measures of phytoplankton, prey fields, and predator locations in their advective context have not been made to establish the ecological importance of horizontal flow. To better understand these important mechanisms, we are deploying a purpose built integrated polar observatory consisting of high frequency radar, coordinated gliders, small boat surveys, and moorings. This integrated polar observatory will enable us to simultaneously sample across the entire food web from the phytoplankton and prey fields to the top predators to understand the ocean features that support life in these polar systems. For the first time in this region, we will: 1) integrate sensors and technologies to simultaneously map phytoplankton blooms, krill aggregations, and top predator foraging relative to dynamic ocean features; 2) integrate these observations with a high-resolution (1.5 km) 3-D dynamic model simulation of the entire WAP coastal ocean to generalize our field measurements to other known hotspots along the WAP through simulation, and to determine which physical mechanisms lead to the maintenance of these hotspots.

The west Antarctic Peninsula (WAP) region has undergone significant changes in temperature and seasonal ice dynamics since the mid-twentieth century, with strong impacts on the regional ecosystem, ocean chemistry and hydrographic properties. Changes to these long-term trends of warming and sea ice decline have been observed in the 21st century, but their consequences for ocean physics, chemistry and the ecology of the high-productivity shelf ecosystem are yet to be fully established. The WAP shelf is important for regional krill stocks and higher trophic levels, whilst the degree of variability and change in the physical environment and documented biological and biogeochemical responses make this a model system for how climate and sea ice changes might restructure high-latitude ecosystems. Although this region is arguably the best-measured and best-understood shelf region around Antarctica, significant gaps remain in spatial and temporal data capable of resolving the atmosphere-ice-ocean-ecosystem feedbacks that control the dynamics and evolution of this complex polar system. Here we summarise the current state of knowledge regarding the key mechanisms and interactions regulating the physical, biogeochemical and biological processes at work, the ways in which the shelf environment is changing, and the ecosystem response to the changes underway. We outline the overarching cross-disciplinary priorities for future research, as well as the most important discipline-specific objectives. Underpinning these priorities and objectives is the need to better define the causes, magnitude and timescales of variability and change at all levels of the system. A combination of traditional and innovative approaches will be critical to addressing these priorities and developing a co-ordinated observing system for the WAP shelf, which is required to detect and elucidate change into the future. Fil: Henley, Sian F.. University of Edinburgh; Reino Unido Fil: Schofield, Oscar M.. State University of New Jersey; Estados Unidos Fil: Hendry, Katharine R.. University Of Bristol; Reino Unido Fil: Schloss, Irene Ruth. Universidad Nacional de Tierra del Fuego; Argentina. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Steinberg, Deborah K.. Virginia Institute of Marine Science. College of William and Mary; Estados Unidos Fil: Moffat, Carlos. University of Delaware; Estados Unidos Fil: Peck, Lloyd S.. British Antarctic Survey; Reino Unido Fil: Costa, Daniel P.. University of California Santa Cruz; Estados Unidos Fil: Bakker, Dorothee C.E.. University of East Anglia; Reino Unido Fil: Hughes, Claire. University Of California, Santa Cruz; Fil: Rozema, Patrick D.. University of East Anglia; Reino Unido Fil: Ducklow, Hugh W.. Columbia University; Estados Unidos Fil: Abele, Doris. Alfred Wegener Institute; Alemania Fil: Stefels, Jacqueline. University of Groningen; Países Bajos Fil: Van Leeuwe, Maria A.. University of Groningen; Países Bajos Fil: Brussaard, Corina P.D.. Royal Netherlands Institute for Sea Research; Países Bajos Fil: Buma, Anita G.J.. University of Groningen; Países Bajos Fil: Kohut, Josh. Royal Netherlands Institute For Sea Research - Nioz; Fil: Sahade, Ricardo Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentina. University Of Groningen; Fil: Friedlaender, Ari S.. State University of New Jersey; Estados Unidos Fil: Stammerjohn, Sharon E.. State University of Colorado at Boulder; Estados Unidos Fil: Venables, Hugh J.. British Antarctic Survey; Reino Unido Fil: Meredith, Michael. British Antarctic Survey; Reino Unido

Along the Western Antarctic Peninsula, ecological hotspots are spatially coherent with submarine canyons and have persisted for millennia. Palmer Deep Canyon, a representative hotspot, is known to have higher phytoplankton biomass than the surrounding non-canyon regions. The physical mechanisms that maintain and deliver phytoplankton and Antarctic krill biomass, potentially increasing prey availability to predators, are not well known. To better understand these important mechanisms, we deployed a purpose built integrated polar observatory consisting of high frequency radar, coordinated gliders, and moorings. The gliders identified a depth dependent influence of the underlying canyon bathymetry on physical and biological variability. A series of simulated particle release experiments in the HF radar current maps were used to estimate surface residence time and connectivity across the canyon. With an average residence time of 2 days, our analysis indicates that the elevated phytoplankton biomass over the central canyon is transported into and out of the hotspot on time scales much shorter than the observed phytoplankton growth rate, suggesting that the canyon may not act as an incubator of phytoplankton productivity as previously suggested. It may instead serve more as a conveyor belt of phytoplankton biomass produced elsewhere, continually replenishing the phytoplankton biomass for the local krill community, which in turn supports numerous top predators.

Discovering the predictors of foraging locations can be challenging, and is often the critical missing piece for interpreting the ecological significance of observed movement patterns of predators. This is especially true in dynamic coastal marine systems, where planktonic food resources are diffuse and must be either physically or biologically concentrated to support upper trophic levels. In the Western Antarctic Peninsula, recent climate change has created new foraging sympatry between Adélie (Pygoscelis adeliae) and gentoo (P. papua) penguins in a known biological hotspot near Palmer Deep canyon. We used this recent sympatry as an opportunity to investigate how dynamic local oceanographic features affect aspects of the foraging ecology of these two species. Simulated particle trajectories from measured surface currents were used to investigate the co-occurrence of convergent ocean features and penguin foraging locations. Adélie penguin diving activity was restricted to the upper mixed layer, while gentoo penguins often foraged much deeper than the mixed layer, suggesting that Adélie penguins may be more responsive to dynamic surface convergent features compared to gentoo penguins. We found that, despite large differences in diving and foraging behavior, both shallow-diving Adélie and deeper-diving gentoo penguins strongly selected for surface convergent features. Furthermore, there was no difference in selectivity for shallow- versus deep-diving gentoo penguins. Our results suggest that these two mesopredators are selecting surface convergent features, however, how these surface signals are related to subsurface prey fields is unknown.

Gliders have proven to be effective tools for sampling the ocean and their modular nature allows for a wide range of missions. Their modularity, adaptive sampling capabilities, and near-real-time data allow them to serve many different communities, from sensor engineers to education/outreach communities. The ability to incorporate new sensors onboard allows scientific capabilities to evolve. Their ability to operate for sustained periods under extreme conditions allows scientists to study processes not possible using ships. Finally, we have found robots are a particularly effective means of entraining students and the general public in ocean exploration. This chapter will highlight these applications.

High-frequency radar (HFR) surface current data are an increasingly utilized tool for capturing complex dynamics of coastal ocean systems worldwide. The radar is uniquely capable of sampling relevant temporal and spatial scales of nearshore processes that impact event response activities and basic coastal ocean research. HFR is a shore-based remote sensing system and is therefore subject to data gaps, which are predominately due to environmental effects, like increased external noise or low signal due to ocean surface conditions. Many applications of these surface current data require that these gaps be filled, such as Lagrangian numerical models, to estimate material transport and dispersion. This study introduces a new penalized least squares regression method based on a three-dimensional discrete cosine transform method to reconstruct hourly HFR surface current data with a horizontal resolution of 6 km. The method explicitly uses both time and space variability to predict the missing value. Furthermore, the method is fast, robust, and requires relatively low computer memory storage. This paper evaluates the method against two scenarios of common data gaps found in HFR networks currently deployed around the world. The validation is based on observed surface current maps along the mid-Atlantic coast of the United States with specific vectors removed to replicate these common gap scenarios. The evaluation shows that the new method is robust and particularly well suited to fill a more common scenario with complete data coverage surrounding an isolated data gap. It is shown that the real-time application of the method is suitable for filling data gaps in large oceanography datasets with high accuracy.

During January–February 2011 standing stocks of phytoplankton (chl a) in the Pennell Bank region of the Ross Sea were variable over 10–100 km spatial scales. One area of elevated chl a on central Pennell Bank (CPB) appeared to be a recurrent mid-summer feature. The western flank (WF) of Pennell Bank had pronounced signatures of Modified Circumpolar Deep Water (MCDW). We evaluated the spatial extent of Fe limitation and net primary production and tested whether MCDW may provide elevated amounts of Fe to the CPB region, through a combination of in situ measurements, shipboard incubations and a horizontally resolved physical model. Regional fluxes of dissolved Fe from deep to surface waters were compared to calculated Fe demands. Low in situ variable to maximum fluorescence (Fv/Fm; 0.24–0.37) and surface water dissolved Fe concentrations (� 0.12–0.21 nM) were suggestive of widespread limitation, corroborated by the consistent responses (Fv/Fm, growth, and nutrient removal ratios) of incubation treatments to Fe addition. MCDW from the WF region had lower dissolved Fe concentrations than that measured in CDW (Circumpolar Deep Water), which suggests on-shelf modification with Fe deplete surface waters and is consistent with the lack of stimulation due to incubation amendments with filtered MCDW. Model results and empirical data suggest MCDW from the WF region is further modified and mixed en route to the CPB region, leading to both the erosion of the canonical MCDW signature and an elevated dissolved Fe inventory of CPB region deep water. This suggests the addition of Fe possibly via diagenesis, as suggested by Marsay et al. (2014). Calculated deep water supply rates to the surface waters of CPB were � 0.18–0.43 m d � 1 , while calculated rates at the WF or northern Pennell Bank (NPB) regions were negative. The CPB populations exhibited � 4.5-fold higher net production rates compared to those in the WF and NPB regions and required 520–3200 nmol Fe m � 2 d � 1 . The modeled vertical supply rates seem to provide � 2–15% of the estimated Fe requirement. Since this flux is based on subsurface dissolved Fe inventories, it does not account for any bioavailable Fe from deep water particulate sources or for Fe recycling in the upper water column. These data suggest the recurrent productivity hotspots at CPB are not fueled by Fe-rich MCDW but are partially supported by the delivery of Fe through vertical exchange processes. & 2015 Published by Elsevier Ltd.

For many people, the Polar Regions remain distant locations, unconnected to their lives, and far from their daily concern. Funded by the National Science Foundation, the goal of the Polar Interdisciplinary Coordinated Education (Polar-ICE) program was to engage the public in understanding how Polar Regions influence our lives while improving their understanding of how scientists work to measure and understand the changing Polar Regions and the global climate system. Through this work, the need emerged for a unified set of messages about the Polar Regions that identify the “big ideas” all people should know about the Poles, the regions which regulate the Earth’s climate. The messages can save as the infrastructure to enable scientists to construct more effective Broader Impacts Projects to engage the public in learning about the Polar Regions end for educators to integrate these big ideas into their STEM teaching both in school and out-of-school learning environments.

Today’s students will be challenged over their professional lifetimes to provide society with 60% more food, 55% more water and 80% more energy for a growing global population forecast to exceed 9 billion by 2050. This can only be realized through scientific understanding that applies emerging technologies to optimize sustained observations and forecasts. It requires a workforce with a variety of skills capable of working together as a team to operate new observing technologies in frontier areas, curate the data flow, and produce forecasts with quantifiable uncertainties appropriate to inform decision makers. They will be faced with real data and imperfect models, and will be required to turn it into actionable information. That data is never perfect, and one must see the sensors and platforms, and understand how they work, to fully understand their limitations. To address these issues, Rutgers University has developed new educational programs focused on conducting research by analyzing authentic data collected and delivered to shore in near real-time from the growing global network of ocean observatories. Here we summarize our undergraduate research track and introduce a Masters of Integrated Ocean Observing based on a series of new courses, a software/QA/QC bootcamp, and research symposia. The students graduating from this program will be prepared to join the blue economy with the skills to operate, analyze, and assess data generated from Ocean Observing Systems in support of scientific research and societal applications.

A collaborative project to integrate a Laser In-Situ Scattering and Transmissometry (LISST) into a Slocum glider was recently completed. This integrated system is capable of measuring particle size, concentration, and beam attenuation, among other standard LISST measurements from a single profiling sensor onboard an autonomous underwater glider coincident with a suite of additional integrated sensors. These integrated LISST-glider sensors provide the unique opportunity to measure suspended particle properties persistently at single locations or survey regional domains, and enable sampling during extreme events such as hurricanes or coastal storms. In this study we detail the sensor integration as well as preliminary data from instrument field tests.

The Mid Atlantic Ocean Observing System (MARACOOS) conducted a validation experiment of its High Frequency radar network from May 10 to July 12, 2016. The goal of the experiment was to evaluate its two surface current products, test quality control software and algorithms and evaluate new bistatic data streams. The experiment was conducted in collaboration with the United States Coast Guard Office of Search and Rescue and RPS an environmental consulting company. The Coast Guard provided 9 drifters that were deployed in the coverage area of the radar network. Six were deployed south of Martha's Vineyard and 3 were deployed off New Jersey, which focused on the validation of the 13 MHz network. The position data from the drifters was used to generate surface drift velocity estimates. These velocity estimates were compared against the radial velocity measurements of the radars. The actual path of the drifters over 48 hours was compared against virtual paths generated using the radar currents and other surface current estimates. The Lagrangian skill score was computed for several different surface current products. The regional surface current product from MARACOOS proved to be the best at predicting the path of the drifters.

Palmer Deep canyon along the central West Antarctic Peninsula is known to have higher phytoplankton biomass than the surrounding non-canyon regions, but the circulation mechanisms that transport and locally concentrate phytoplankton and Antarctic krill, potentially increasing prey availability to upper-trophic-level predators such as penguins and cetaceans, are currently unknown. We deployed a three-site high-frequency radar network that provided hourly surface circulation maps over the Palmer Deep hotspot. A series of particle release experiments were used to estimate surface residence time and connectivity across the canyon. The majority of residence times fell between 1.0 and 3.5 days, with a mean of 2 days and a maximum of 5 days. We found a highly significant negative relationship between wind speed and residence time. Our residence time analysis indicates that the elevated phytoplankton biomass over the central canyon is transported into and out of the hotspot on time scales much shorter than the observed phytoplankton growth rate, suggesting that the canyon may not act as an incubator of phytoplankton productivity as previously suggested. It may instead serve more as a conveyor belt of phytoplankton biomass produced elsewhere, continually replenishing the phytoplankton biomass for the local Antarctic krill community, which in turn supports numerous top predators. This article is part of the theme issue ‘The marine system of the West Antarctic Peninsula: status and strategy for progress in a region of rapid change’.

Taking the 2011 summer bloom as a study case, we investigated the transport and nutrient delivery mechanisms for large phytoplankton blooms of the New Jersey coast. The horizontal advection of the chlorophyll is approximately one order larger than the horizontal diffusion averaging the whole study area. And the sea surface currents are found to correlate with the wind stress but only for part of the middle shelf. Based on the horizontal advection simulation driven by HF radar current, the bloom is divided into three sub-regions. The northern coastal section of the bloom shows high–low–high pattern in chlorophyll time series, which is related to coastal upwelling and a clockwise eddy. Coastal currents play an important role in the eddy formation and the southward transport of the bloom. The southern coastal section of the bloom is supported by the nutrients from coastal upwelling and driven offshore by wind. The northeast section of the bloom is fueled by nutrient source upwelled through Ekman pumping. The magnitude of Ekman pumping is of the same order as the magnitude of the upwelling along the coast. These identified mechanisms could also applied to more than half of bloom events during 2002 to 2013. In the summer of 2011 off the coast of New Jersey, processes in different sub-regions worked together, leading to this large phytoplankton bloom.

Regional sediment resuspension and transport are examined as Hurricane Sandy made landfall on the Mid-Atlantic Bight (MAB) in October 2012. A Teledyne-Webb Slocum glider, equipped with a Nortek Aquadopp current profiler, was deployed on the continental shelf ahead of the storm, and is used to validate sediment transport routines coupled to the Regional Ocean Modeling System (ROMS). The glider was deployed on 25 October, 5 days before Sandy made landfall in southern New Jersey (NJ) and flew along the 40 m isobath south of the Hudson Shelf Valley. We used optical and acoustic backscatter to compare with two modeled size classes along the glider track, 0.1 and 0.4 mm sand, respectively. Observations and modeling revealed full water column resuspension for both size classes for over 24 h during peak waves and currents, with transport oriented along-shelf toward the southwest. Regional model predictions showed over 3 cm of sediment eroded on the northern portion of the NJ shelf where waves and currents were the highest. As the storm passed and winds reversed from onshore to offshore on the southern portion of the domain waves and subsequently orbital velocities necessary for resuspension were reduced leading to over 3 cm of deposition across the entire shelf, just north of Delaware Bay. This study highlights the utility of gliders as a new asset in support of the development and verification of regional sediment resuspension and transport models, particularly during large tropical and extratropical cyclones when in situ data sets are not readily available.

Mixed-layer depth (MLD) has been widely linked to phytoplankton dynamics in Antarctica's coastal regions; however, inconsistent definitions have made intercomparisons among region-specific studies difficult. Using a data set with over 20,000 water column profiles corresponding to 32 Slocum glider deployments in three coastal Antarctic regions (Ross Sea, Amundsen Sea, and West Antarctic Peninsula), we evaluated the relationship between MLD and phytoplankton vertical distribution. Comparisons of these MLD estimates to an applied definition of phytoplankton bloom depth, as defined by the deepest inflection point in the chlorophyll profile, show that the maximum of buoyancy frequency is a good proxy for an ecologically relevant MLD. A quality index is used to filter profiles where MLD is not determined. Despite the different regional physical settings, we found that the MLD definition based on the maximum of buoyancy frequency best describes the depth to which phytoplankton can be mixed in Antarctica's coastal seas.

Coastal salinity is a basic oceanographic property that is not routinely estimated by satellites. Efforts to measure ocean salinity from space are designed for large scale open ocean environments, not coastal regions. In the Mid-Atlantic coastal ocean, salinity is critical for understanding circulation patterns, river plumes, and transport, which in turn impact the status of the ecosystem. However, the spatial and temporal coverage of in situ salinity measurements in this region are sparse and do not synoptically capture salinity in the coastal ocean. We compiled ∼2 million salinity records from four regional research vessels between the years 2003–2008 and found ∼9 thousand salinity records that could be adequately matched to MODIS-Aqua data. We show that the spectral shape of water-leaving radiance and sea surface temperature are most correlated with in situ salinity. Four neural network models designed to predict salinity were developed for the Mid-Atlantic coastal region and three of its major estuaries (Hudson, Delaware, and Chesapeake). Our models predict salinity with RMS errors between 1.40 psu and 2.29 psu, which are much less than the null model ranges (4.87–10.08 psu) and the natural range of the system (0–32 psu). Seasonal climatologies for the Chesapeake, Delaware, and Mid-Atlantic regions based on these models are fresher than the existing NODC climatologies. We also found significant freshening trends in the Mid-Atlantic over a 6 year period.

A paper was presented at OCEANS '15 on a new way of increasing the resiliency of a High Frequency radar network through the use of bistatic measurements. This was modeled on the Mid Atlantic Regional Association Coastal Ocean Observing System (MARACOOS) High Frequency Radar network. The bistatic operating system is a recent feature of the SeaSonde HF radar. The bistatic capability is a viable way of increasing resiliency with out increasing the number of antennae. It involves the separation of the transmit and receive stations, as well as GPS timing to coordinate the time of the transmission signals. This results in a switch from a radial geometry and measurement to an elliptical geometry and measurement. This allows for higher percentage of overlapping coverage, which could potentially increase accuracy and resiliency. Using the configuration found through the previous models, bistatics were implemented along the MARACOOS network. Currently three radar stations are operating bistataically and generating elliptical current maps. They are stations located in North Wildwood (WOOD), Strathmere (RATH), and Brigantine (BRMR) New Jersey. The results have shown promise that the elliptical current measurements can become part of the operational data stream for the radar network. The bistatic systems are renamed using the first two letters of the four-letter station codes. For example the Strathmere-Brigantine bistatic system is called RABR. Initial findings suggest that the RABR is getting better coverage than the RAWO station. Using bistatics in RABR has widened the coverage area. Accuracy and coverage will be closely monitored during this time.

The integration of a FIRe sensor into a glider allows us to map, with high temporal and spatial resolution, phytoplankton physiological responses to physical forcing. Different missions were designed to evaluate the temporal and spatial variability of phytoplankton physiology by using a drift and a station keeping mission, respectively. Diel cycles collected show a clear diurnal variations driven by incident radiation, with both maximal fluorescence and photosynthetic efficiency (in any light adapted phytoplankton) showing reduced values only in the upper 10–15 meters of the water column at the highest irradiances. Further analyses comparing different MLD regimes have shown different photoacclimation responses (light saturation parameter, Ek) resulting from differences in solar radiation exposure conditions (both time and intensity), reflected in the depth of the ML. Further analyses include determining a method to correct the FIRe glider fluorescence profiles in the upper ocean during daytime by comparing the maximum fluorescence during the highest irradiance (daytime) with the lowest irradiance (nighttime).

On the continental shelf of the west Antarctic Peninsula (WAP), waters below the permanent pycnocline are strongly influenced by intrusions of water masses shed from the Antarctic Circumpolar Current. These intrusions carry relatively warm water toward the coast and to glacier grounding lines, but intrusion locations, mechanisms, and pathways by which this water moves on the shelf are still poorly understood. Dozens of deployments of autonomous underwater vehicles (gliders) in the vicinity of Palmer Deep, a biologically productive canyon on the WAP, have collected temperature and salinity data at extremely high spatial resolution. These data can be used to calculate geostrophic currents in the across-glider-track direction, and this would provide an extensive dataset to study circulation on the WAP shelf, but the relative importance of the geostrophic component to the total current field must first be determined. Here, we present a comparison between one ADCP transect and several repeat glider transects along the same line. Velocities measured by the ADCP are difficult to compare to geostrophic velocities because the shallowest ADCP bin is 46 m below the surface, while geostrophic velocities are referenced to dead-reckoned velocities with a significant contribution from surface currents. Despite limitations, depth-averaged geostrophic currents show promise in being a useful proxy for total depth-average currents on the WAP. The depth-averaged currents from glider deployments show significant day-to-day variability in both magnitude and direction, but the glider transect timed most closely to the ADCP transect showed a similar pattern. Vertical shear is predominantly directed onshore, and measurements of shear below the permanent pycnocline are small compared to those at the surface.

There are approximately 300 High Frequency (HF) radars deployed around the globe making real time measurements of the surface currents in the coastal ocean. In the United States, the HF radar network within the Mid Atlantic Regional Association Coastal Ocean Observing System (MARACOOS) became operational with the United States Coast Guard in May 2009. This model was expanded nationally and the Integrated Ocean Observing System (IOOS) National HF Radar Network became operational with the Coast Guard in March 2011. Much of the quality control that is done with the data requires a person in the loop to be inspecting the data. We present several metrics and techniques to automate the quality control process to ensure that the radial and total velocity measurements are accurate. We have used average radial bearing, spectra merged count, radial count and data latency as measurements that are useful in assessing the performance of the network. Some of those techniques include real time comparisons with ADCPs and comparison of the detided total vector fields with nearby wind measurements. We also present metrics to gauge the performance of the network over seasonal and yearly time scales. The goal of the network is to provide surface currents to the Coast Guard over 80% of the spatial region of the Mid Atlantic over 80% of the time. The spatial grid that the network could realistically cover contained all grid points within 150 km of the coast and out beyond the 15 m isobath. We have also developed a user interface for the operators to control what radial sites contribute to the total vector generation. As discussed at the Radiowave Oceanography Working Group (ROWG) meetings it is the responsibility of the region to provide quality-controlled data to the National Network. Currently the National Network has only two checks for the radial data 1) that the radial measurement is over water and 2) that the magnitude of the radial measurement is below a certain threshold based on the region of the measurement. This model where radial data is inspected at the regional level before being sent onto the National Network can be expanded to the other 10 regions of the country. This also keeps the decision of what data is correct where the local knowledge of the current structure is best understood. We saw that these techniques can eliminate errors in the data stream. This also acts as a feedback mechanism to the operators to evaluate their performance in operating and maintaining the radars. The techniques discussed here can serve as data quality checks for the vast number of systems operating today. They will ensure that the data being produced is of the highest quality, which will in turn ensure that the products being generated with this data are sound and reliable.

The Middle Atlantic Bight (MAB) exhibits one of the largest seasonal cycles of temperature in the global ocean. During the summer, the water column is strongly stratified with warm surface waters separated from much colder bottom waters by a strong, shallow thermocline. The bottom water that remains cold in the summer months is referred to as the ‘cold pool’. The cold pool is formed as the stratification sets up in late spring and it remains until fall mixing breaks down the seasonal thermocline with each passing storm; it usually breaks down in September or October. The cold pool is an important feature of the MAB as it influences the surrounding waters, the intensity of storms, and fish assemblages over the MAB. We use various data sources to explore interannual variability and long-term climatic trends in summer stratification and cold pool source water. Annual trawls conducted by the National Oceanic and Atmospheric Administration National Marine Fisheries Services (NOAA NMFS) provide temperature and salinity measurements consistently from 1980 to the present. Slocum gliders have been regularly deployed along New Jersey shelf since 2003 and collect data for various organizations such as Rutgers University and the Environmental Protection Agency. NOAA's National Data Buoy Center provides several buoys in the region that have been collecting data since the early 1980's. A better understanding of the cold pool can lead to a better understanding of ocean and storm interactions in the MAB and of potential climate change impacts on the region.

The Palmer Deep submarine canyon on the Western Antarctic Peninsula provides a conduit for upwelling of relatively warm, nutrient rich waters which enhance local primary production and support a food web productive enough to sustain a large top predator biomass. In an analysis of ten years of satellite-tagged penguins, showed that circulation features associated with tidal flows may be a key driver of nearshore predator distributions. During diurnal tides, the penguins feed close to their breeding colonies and during semi-diurnal tides, the penguins make foraging trips to the more distant regions of Palmer Deep. It is hypothesized that convergent features act to concentrate primary producers and aggregate schools of krill that influence the behavior of predator species. The initial results from a six month deployment of a High Frequency Radar network in Palmer Deep are presented in an attempt to characterize and quantify convergent features. During a three month period from January through March 2015, we conducted in situ sampling consisting of multiple underwater glider deployments, small boat acoustic surveys of Antarctic krill, and penguin ARGOS-linked satellite telemetry and time-depth recorders (TDRs). The combination of real-time surface current maps with adaptive in situ sampling introduces High Frequency Radar to the Antarctic in a way that allows us to rigorously and efficiently test the influence of local tidal processes on top predator foraging ecology