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This article resurfaces an enslaved female whom we encounter, drowning, in the archive of the Middelburgse Commercie Compagnie (MCC). To unfold a reading beyond the transcription of her commodified death, I investigate the five localities that conditioned her bodily inscription into history: the archive, the law, the ship, the ocean, and the womb. Traveling through these localities, I disclose, at once, the historical violence against black females through the transatlantic slave trade system and the excess black females proved to be to this very system. Excessive thus, black female lineage provides an alternative to white, patriarchic systems of relation.

AbstractKinetic energy associated with inertia–gravity waves (IGWs) and other ageostrophic phenomena often overwhelms kinetic energy due to geostrophic motions for wavelengths on the order of tens of kilometers. Understanding the dependencies of the wavelength at which balanced (geostrophic) variability ceases to be larger than unbalanced variability is important for interpreting high-resolution altimetric data. This wavelength has been termed the transition scale. This study uses acoustic Doppler current profiler (ADCP) data along with auxiliary observations and a numerical model to investigate the transition scale in the eastern tropical Pacific and the mechanisms responsible for its regional and seasonal variations. One-dimensional kinetic energy wavenumber spectra are separated into rotational and divergent components, and subsequently into vortex and wave components. The divergent motions, most likely predominantly IGWs, account for most of the energy at wavelengths less than 100 km. The observed regional and seasonal patterns in the transition scale are consistent with those from a high-resolution global simulation. Observations, however, show weaker seasonality, with only modest wintertime increases in vortex energy. The ADCP-inferred IGW wavenumber spectra suggest that waves with near-inertial frequency dominate the unbalanced variability, while in model output, internal tides strongly influence the wavenumber spectrum. The ADCP-derived transition scales from the eastern tropical Pacific are typically in the 100–200-km range.

This article describes three homophonous morphemes ka integral to alignment in Vamale, a South Oceanic language: a relational classifier, a subject marker clitic, and a possessive linker in nominalizations. Northern New Caledonian languages tend towards ergativity, while southern ones favour accusative alignment in all domains. Vamale is spoken near the border between the two and shows a fascinating pattern: one system in nouns, another in verbs, and a third one in nominalizations. Using first-hand field data, this article introduces the relevant concepts with examples and compares Vamale to its neighbours. While the development of this system remains speculative, we argue that the language has assimilated to its powerful neighbour Cèmuhî.

Like many other Oceanic and Kanak languages of New Caledonia, Zuanga-Yuanga [ZY] has classifiers restricted to the possession of nouns denoting food, drink, animals and plants; it also has dichotomous direct and indirect adnominal possessive constructions, which are generally labeled inalienable or alienable in the Oceanic literature. These terms refer to a distinction between close versus distant structural marking, which do not strictly correlate with lexical-semantic categories. For instance, kinship nouns are split over the two types of constructions, distinguishing reference from address kinship terms, not in terms of semantic distinctions between close versus distant kinship types. The split for body-part nouns is between directly possessed dedicated terms and indirectly possessed metaphorical body terms, not in terms of permanent versus removable parts, or temporary body properties. In ZY possessive constructions correlate with fairly strict possessee noun classes belonging to one single structural class (directly or indirectly marked). Only a limited number of nouns denoting parts-of-whole have alternate constructions expressing different semantic relations to the possessed noun.

Abstract: The K-profile parameterization (KPP) is a common method to model turbulent fluxes in regional and global oceanic models. Many versions of KPP exist in the oceanic sciences community, and one of their main differences is how they take the effects of nonbreaking waves into account. Although there is qualitative consensus that nonbreaking waves enhance vertical mixing due to the ensuing Langmuir circulations, there is no consensus on the quantitative aspects and modeling approach. In this paper we use a recently developed method to estimate both components of KPP (the diffusive term, usually called local, and the nondiffusive component, usually called nonlocal) based on numerically simulated turbulent fluxes without any a priori assumptions about their scaling or their shape. Through this method we show that the cubic shape usually used in KPP is not optimal for wavy situations and propose new ones. Furthermore, we show that the formulation for the nondiffusive fluxes, which currently only depend on the presence of surface buoyancy fluxes, should also take wave effects into account. We also investigate how the application of these changes to KPP improves the representation of turbulent fluxes in a diagnostic approach when compared with previous models.

AbstractSurface gravity waves play a major role in the exchange of momentum, heat, energy, and gases between the ocean and the atmosphere. The interaction between currents and waves can lead to variations in the wave direction, frequency, and amplitude. In the present work, we use an ensemble of synthetic currents to force the wave model WAVEWATCH III and assess the relative impact of current divergence and vorticity in modifying several properties of the waves, including direction, period, directional spreading, and significant wave height Hs. We find that the spatial variability of Hs is highly sensitive to the nature of the underlying current and that refraction is the main mechanism leading to gradients of Hs. The results obtained using synthetic currents were used to interpret the response of surface waves to realistic currents by running an additional set of simulations using the llc4320 MITgcm output in the California Current region. Our findings suggest that wave parameters could be used to detect and characterize strong gradients in the velocity field, which is particularly relevant for the Surface Water and Ocean Topography (SWOT) satellite as well as several proposed satellite missions.

Speciation is thought to be predominantly driven by the geographical separation of populations of the ancestral species. Yet, in the marine realm, there is substantial biological diversity despite a lack of pronounced geographical barriers. Here, we investigate this paradox by considering the biogeography of marine mammals: cetaceans (whales and dolphins) and pinnipeds (seals and sea lions). We test for associations between past evolutionary diversification and current geographical distributions, after accounting for the potential effects of current environmental conditions. In general, cetacean lineages are widely dispersed and show few signs of geographically driven speciation, albeit with some notable exceptions. Pinnipeds, by contrast, show a more mixed pattern, with true seals (phocids) tending to be dispersed, whereas eared seals (otariids) are more geographically clustered. Both cetaceans and pinnipeds show strong evidence for environmental clustering of their phylogenetic lineages in relation to factors such as sea temperature, the extent of sea ice, and nitrate concentrations. Overall, current marine mammal biogeography is not indicative of geographical speciation mechanisms, with environmental factors being more important determinants of current species distributions. However, geographical isolation appears to have played a role in some important taxa, with evidence from the fossil record showing good support for these cases.

This essay uses frameworks derived from Archipelagic American studies to examine Tiphanie Yanique’s novel Land of Love and Drowning and the United States Virgin Islands on the 100th anniversary of their transfer from Denmark. Yanique’s vision of a specifically USVI literature is necessarily archipelagic in that it participates in inter-island exchange based on circuits forged by colonial practice that have been dynamically revised through global black freedom struggles taking place in archipelagoes of the Virgin Islands in conjunction with the continents that comprise their diasporic communities. The archipelagic perspective exposes the circuits of connectivity between water, land, human, animals, and commodities that travel through the submarine routes of the Atlantic basin. Using a strategy of literary assemblage to build a diasporic mythology that is nevertheless grounded in the specific ecologies of the USVI allows Yanique to counter trenchant stereotypical portrayals that reify the VI’s historical invisibility in American culture. More urgently, she draws attention to the islands as a forgotten U.S. territory in times of crisis such as the wreckage of hurricanes Irma and Maria. One manifestation of Yanique’s literary assemblage are her fictive hybrids, her “ocean grown” folks; I read Land of Love in Drowning alongside Wangechi Mutu’s Nguva na Nyoka (Sirens and Serpents) and St. Croix-based artist La Vaughn Belle’s video installations/counternarratives of Danish slavery to further illuminate the archipelagic nature of Yanique’s narrative assemblage, which demands a interartistic perspective that considers multiple mediums and modes of exchange and encounter across national and natural boundaries. As Yanique’s generational tale coalesces around the commemoration and nostalgic unease of Transfer, her image-based thematics resonate with Belle’s and Mutu’s visual reckoning with the hybridity of splintered identity that results from an accumulation of colonial legacies and diasporic sensibilities.

AbstractArgo float trajectories are simulated in the southwest Pacific basin (25°–45°S, 170°E–165°W) using velocity fields from a 1/12° Southern Ocean model and a Lagrangian particle tracking model programmed to represent the vertical motions of profiling Argo floats. The system is applied to simulate both core Argo floats (typically parked at 1000-m depth and profiling to 2000-m depth) and Deep Argo floats (parked 500 m above the seafloor). The goal is to estimate probability density functions (PDFs) predicting future float positions. Differences are expected in the trajectory statistics, largely because of limitations in the temporal and spatial resolution of the model fields and uncertainties associated with a random walk component included in the particle advection scheme to represent this unresolved variability. Nonetheless, the core Argo float displacements over ~100-day time intervals are mostly consistent with the derived PDFs, particularly in regions with stable midlayer flows. For the Deep Argo floats, which are released into the open ocean and parked near the bottom, the simulations predict an average total displacement of less than 50 km within 100 days, in good agreement with the Deep Argo floats deployed as part of a pilot study. The study explores both the representativeness and the predictability of float displacements, with an aim to contribute to planning for the float observing system.

Abstract: Argo float trajectories are simulated in the southwest Pacific basin (25°–45°S, 170°E–165°W) using velocity fields from a 1/12° Southern Ocean model and a Lagrangian particle tracking model programmed to represent the vertical motions of profiling Argo floats. The system is applied to simulate both core Argo floats (typically parked at 1000-m depth and profiling to 2000-m depth) and Deep Argo floats (parked 500 m above the seafloor). The goal is to estimate probability density functions (PDFs) predicting future float positions. Differences are expected in the trajectory statistics, largely because of limitations in the temporal and spatial resolution of the model fields and uncertainties associated with a random walk component included in the particle advection scheme to represent this unresolved variability. Nonetheless, the core Argo float displacements over ~100-day time intervals are mostly consistent with the derived PDFs, particularly in regions with stable midlayer flows. For the Deep Argo floats, which are released into the open ocean and parked near the bottom, the simulations predict an average total displacement of less than 50 km within 100 days, in good agreement with the Deep Argo floats deployed as part of a pilot study. The study explores both the representativeness and the predictability of float displacements, with an aim to contribute to planning for the float observing system.

Understanding the transport and accumulation of microplastics is useful to determine the relative risk they pose to global biodiversity. The exact contribution of microplastic sources is hard to elucidate; therefore, investigating the Antarctic Weddell Sea, an area known for its remoteness and little human presence (i.e. limited pollution sources), will help us to better understand microplastic transportation. Here, we investigate the presence of microplastics in a range of Antarctic sample media including air, seawater, and sediment. We hypothesised that multiple transportation processes including atmospheric and oceanic vectors determine the presence of microplastics in the Antarctic. Using techniques including Polarised Light Microscopy and Raman Spectrometry, we identified mostly fibres and categorised them based on their optical and chemical properties. A total of 47 individual microplastic categories (45 of which were fibres) were identified in the air, seawater, and sediment samples. The majority of categories did not overlap multiple media (42/47); however, four fibre categories were present in both air and water samples, and another fibre category was found in all three media (category 27). We suggest that the large variety of fibres identified and the overlap of fibre categories among media indicates that the pollution may result from multiple diffuse sources and transportation pathways. Additionally, our Air Mass Back Trajectory analyses demonstrates that microplastic fibres are being transported by air masses or wind, and strongly suggests that they are transported to the Antarctic from southern South America. We also propose that fibres may be transported into the Antarctic in subsurface waters, and as pollution was identified in our sediment and additional sea ice samples, we suggest that the coastal and Antarctic deep sea may be a sink for microplastic fibres. The results shown here from a remote, near-pristine system, further highlight the need for a global response to the plastic pollution crisis.

Considerable research has concerned the influence of Papua New Guinea's Oceanic languages on the development of the pidgin/creole Tok Pisin, but little research has considered linguistic influence in the opposite direction. This paper adds to both bodies of research by investigating whether the colexification of 'enough', 'able' and 'until' in Papapana (Oceanic) and Tok Pisin results from internal or contact-induced change. Such a colexification is unattested/rare cross-linguistically therefore I argue that language contact is responsible. The Tok Pisin verb inap 'enough, able' grammaticalised as the preposition/subordinator 'until' because of semantic extensions by Oceanic language speakers whose languages demonstrate overlapping polysemies. The Papapana verb eangoi colexifies 'enough' and 'able' (common cross-linguistically), but the colexification with the lexicalised adverb eangoiena 'able' and grammaticalised preposition/subordinator eangoiena 'until' is pattern replication modelled on Tok Pisin. Based on areal data, I propose a tentative semantic map for ENOUGH, contributing to research on cross-linguistic colexification. [ABSTRACT FROM AUTHOR]

The paper reports on the deep geophysical studies performed by the Geological Survey of Russia (VSEGEI) under the international project – Deep Processes and Metallogeny of Northern, Central and Eastern Asia. A model of the deep crustal structure is represented by a set of crustal thickness maps and a 5400-km long geotransect across the major tectonic areas of Northeastern Eurasia. An area of 50000000 km2 is digitally mapped in the uniform projection. The maps show the Moho depths, thicknesses of the main crustal units (i.e. the sedimentary cover and the consolidated crust), anomalous gravity and magnetic fields (in a schematic zoning map of the study area), and types of the crust. The geotransect gives the vertical section of the crust and upper mantle at the passive margin of the Eurasian continent (including submarine uplifts and shelf areas of the Arctic Ocean) and the active eastern continental margin, as well as an area of the Pacific plate.

This article discusses an indigenous methodological framework employed in the development of my doctoral study, ‘Asi – The Presence of the Unseen. Considering the Tongan concept of ‘asi (the unseen spirit that energises and gives agency to artistic work), the thesis asked, “What occurs when young Oceanic people work together creatively in a group, drawing on values from their cultural heritage to develop meaningful faiva (artistic performance)?” In posing this question, the study sought to understand how ‘asi might bring forward a powerful sense of belonging and co-creation that might resource artistic practice. As such, I proposed that the ‘asi identifiable at the peak of a performance, might be also be discernible before and after such an event. The methodological framework for the study drew its inspiration from approaches to making Tongan bark cloth fabric (ngatu). Given the co-creative nature of such work, the Ngatu framework positioned the investigator as both an artistic practitioner and a reflector on the practices and experiences of other people collaborating in the study.

Ciliates are abundant microplankton that are widely distributed in the ocean. In this paper, the distribution patterns of ciliate diversity in the South China Sea (SCS) were analyzed by compiling community data from previous publications. Based on morphological identification, a total of 592 ciliate species have been recorded in the SCS. The ciliate communities in intertidal, neritic and oceanic water areas were compared in terms of taxonomy, motility and feeding habit composition, respectively. Significant community variation was revealed among the three areas, but the difference between the intertidal area and the other two areas was more significant than that between neritic and oceanic areas. The distributions of ciliates within each of the three areas were also analyzed. In the intertidal water, the community was not significantly different among sites but did differ among habitat types. In neritic and oceanic areas, the spatial variation of communities among different sites was clearly observed. Comparison of communities by taxonomic and ecological traits (motility and feeding habit) indicated that these traits similarly revealed the geographical pattern of ciliates on a large scale in the SCS, but to distinguish the community variation on a local scale, taxonomic traits has higher resolution than ecological traits. In addition, we assessed the relative influences of environmental and spatial factors on assembly of ciliate communities in the SCS and found that environmental selection is the major process structuring the taxonomic composition in intertidal water, while spatial processes played significant roles in influencing the taxonomic composition in neritic and oceanic water. Among ecological traits, environmental selection had the most important impact on distributions. [ABSTRACT FROM AUTHOR]

Ciliates are abundant microplankton that are widely distributed in the ocean. In this paper, the distribution patterns of ciliate diversity in the South China Sea (SCS) were analyzed by compiling community data from previous publications. Based on morphological identification, a total of 592 ciliate species have been recorded in the SCS. The ciliate communities in intertidal, neritic and oceanic water areas were compared in terms of taxonomy, motility and feeding habit composition, respectively. Significant community variation was revealed among the three areas, but the difference between the intertidal area and the other two areas was more significant than that between neritic and oceanic areas. The distributions of ciliates within each of the three areas were also analyzed. In the intertidal water, the community was not significantly different among sites but did differ among habitat types. In neritic and oceanic areas, the spatial variation of communities among different sites was clearly observed. Comparison of communities by taxonomic and ecological traits (motility and feeding habit) indicated that these traits similarly revealed the geographical pattern of ciliates on a large scale in the SCS, but to distinguish the community variation on a local scale, taxonomic traits has higher resolution than ecological traits. In addition, we assessed the relative influences of environmental and spatial factors on assembly of ciliate communities in the SCS and found that environmental selection is the major process structuring the taxonomic composition in intertidal water, while spatial processes played significant roles in influencing the taxonomic composition in neritic and oceanic water. Among ecological traits, environmental selection had the most important impact on distributions.

Networks of no-take marine protected areas (MPAs), where all extractive activities are prohibited, are the most effective tool to directly protect marine ecosystems from destructive and unsustainable human activities. No-take MPAs and MPA networks have been globally implemented in coastal seas, and their success has been significantly enhanced where science-based biophysical guidelines have informed their design. Increasingly, as human pressure on marine ecosystems is expanding further offshore, governments are establishing offshore MPAs—some very large—or MPA networks. Globally, there are growing calls from scientists, non-government organisations, and national governments to set global conservation targets upwards of 30%. Given that most of the ocean is found either in the high seas or offshore within national Exclusive Economic Zones, large offshore MPAs or networks of MPAs must be a major component of these global targets for ocean protection. However, without adequate design, these offshore MPAs risk being placed to minimise conflict with economic interests, rather than to maximise biodiversity protection. This paper describes detailed biophysical guidelines that managers can use to design effective networks of no-take MPAs in offshore environments. We conducted a systematic review of existing biophysical design guidelines for networks of MPAs in coastal seas, and found consistent elements relating to size, shape, connectivity, timeframes, and representation of biophysical features. However, few of the guidelines are tailored to offshore environments, and few of the large offshore MPAs currently in place were designed systematically. We discuss how the common inshore design guidelines should be revised to be responsive to the characteristics of offshore ecosystems, including giving consideration of issues of scale, data availability, and uncertainty. We propose 10 biophysical guidelines that can be used to systematically design offshore networks of MPAs which will also contribute to the global goal of at least 30% protection globally. Finally, we offer three priority guidelines that reflect the unique conservation needs of offshore ecosystems: emphasising the need for larger MPAs; maximising the inclusion of special features that are known and mapped; and representing minimum percentages of habitats, or, where mapped, bioregions. Ultimately, MPA guidelines need to be embedded within an adaptive management framework, and have the flexibility to respond to emerging knowledge and new challenges.

The Red-fin Goby, Evorthodus minutus Meek & Hildebrand, 1928, is a coastal brackish species which is commonly distributed from Sinaloa, Mexico to Guayaquil, Ecuador and particularly abundant in mangroves of Central American eastern Pacific. We report a new record of E. minutus collected from the Santa Cruz Island, part of the Galapagos Archipelago. This new record represents a range extension and is allows for a relevant discussion about colonization pathways in the equatorial eastern Pacific of a brackish-water species.

Between 5% and 25% of the total momentum transferred between the atmosphere and ocean is transmitted via the growth of long surface gravity waves called ''swell.'' In this paper, we use large-eddy simulations to show that swell-transmitted momentum excites near-inertial waves and drives turbulent mixing that deepens a rotating, stratified, turbulent ocean surface boundary layer. We find that swell-transmitted currents are less effective at producing turbulence and mixing the boundary layer than currents driven by an effective surface stress. Overall, however, the differences between swell-driven and surface-stress-driven boundary layers are relatively minor. In consequence, our results corroborate assumptions made in Earth system models that neglect the vertical structure of swell-transmitted momentum fluxes and instead parameterize all air--sea momentum transfer processes with an effective surface stress. [ABSTRACT FROM AUTHOR]

The widely used Fast Microwave Ocean Surface Emissivity Model (FASTEM) does not include the interaction between small-scale and large-scale roughness, which seems to induce errors in the ocean surface emissivity estimation. In this study, we attempt to develop a new model that might be included in the FASTEM-like model. In the developed model, the large-scale roughness is expressed as a function of the local incidence angle (LIA) within the context of Fresnel reflection theory, incorporating the interactions between the small-scale and large-scale roughness into the fast ocean surface emissivity model, as done in the two-scale approach. With the new expression of the large-scale roughness, we also provide a more physically based form of the equation for the fast ocean surface emissivity calculation that includes the small-scale scattering over a geometrically rough surface. In addition, an algorithm for estimating two-scale roughness from the measured or modeled polarized emissivities in conjunction with the proposed fast ocean surface emissivity equation is provided. The results demonstrate that the interactions between two-scale roughness should be considered in order to estimate accurate two-scale roughness influences on the ocean surface emissivity. [ABSTRACT FROM AUTHOR]

The California Current System is thought to be particularly vulnerable to ocean acidification, yet pH remains chronically undersampled along this coast, limiting our ability to assess the impacts of ocean acidification. To address this observational gap, we integrated the Deep-Sea-DuraFET, a solid-state pH sensor, onto a Spray underwater glider. Over the course of a year starting in April 2019, we conducted seven missions in central California that spanned 161 glider days and >1600 dives to a maximum depth of 1000 m. The sensor accuracy was estimated to be ± 0.01 based on comparisons to discrete samples taken alongside the glider (n = 105), and the precision was ± 0.0016. CO2 partial pressure, dissolved inorganic carbon, and aragonite saturation state could be estimated from the pH data with uncertainty better than ± 2.5%, ± 8 μmol kg-1, and ± 2%, respectively. The sensor was stable to ± 0.01 for the first 9 months but exhibited a drift of 0.015 during the last mission. The drift was correctable using a piecewise linear regression based on a reference pH field at 450 m estimated from published global empirical algorithms. These algorithms require accurate O2 as inputs; thus, protocols for a simple predeployment air calibration that achieved accuracy of better than 1% were implemented. The glider observations revealed upwelling of undersaturated waters with respect to aragonite to within 5 m below the surface near Monterey Bay. These observations highlight the importance of persistent observations through autonomous platforms in highly dynamic coastal environments. [ABSTRACT FROM AUTHOR]

This paper applies scholarship in the environmental humanities specifically related to oceanic imaginary in order to examine tourist narratives portrayed in two science fiction stories from the anthology, Drowned Worlds: Tales from the Anthropocene and Beyond. The two stories in question are Ken Liu's "Dispatches from the Cradle: The Hermit--Forty-Eight Hours in the Sea of Massachusetts" and Nalo Hopkinson's "Inselberg". Both stories explore the intersecting difficulties brought about by tourist demand and rising sea tides. The meeting point of these two phenomena in the context of "Dispatches" and "Inselberg" depicts traumatised individuals, communities, and landscapes. These stories are unique in their portrayal of the particular vulnerabilities of islands. They explore both individual and collective trauma set against the backdrop of climate catastrophe, which acts as an allegory for the real-world uncertainty faced by humans due to climate change. While the futurity in each story overlaps in a shared narrative of traumatic existence for the individuals and communities they depict, there is one key difference: "Dispatches" emphasises large-scale, exterior systems of power, while "Inselberg" looks inward to one island's struggle for autonomy. Together both stories criticise systems of social and environmental exploitation, which binds the narratives, settings, and characters in cycles of trauma. [ABSTRACT FROM AUTHOR]

The effects of nonbreaking surface waves on upper-ocean dynamics enter the wave-averaged primitive equations through the Stokes drift. Through the resulting upper-ocean dynamics, Stokes drift is a catalyst for the fluxes of heat and trace gases between the atmosphere and ocean. However, estimates of the Stokes drift rely crucially on properly resolving the wave spectrum. In this paper, using state-of-the-art spatial measurements (in situ and airborne remote sensing) from a number of different field campaigns, with environmental conditions ranging from 2 to 13ms21 wind speed and significant wave height of up to 4m, we characterize the properties of the surface wave field across the equilibrium and saturation ranges and provide a simple parameterization of the transition between the two regimes that can easily be implemented in numerical wave models. We quantify the error associated with instrument measurement limitations, or incomplete numerical parameterizations, and propose forms for the continuation of these spectra to properly estimate the Stokes drift. Depending on the instrument and the sea state, predictions of surface Stokes drift may be underestimated by more than 50%. [ABSTRACT FROM AUTHOR]

The irregular nature of vertical profiles of density in the thermocline appears well described by a Poisson process over vertical scales 2-200 m. To what extent does this view of the thermocline conflict with established models of the internal wavefield? Can a one-parameter Poisson subrange be inserted between the larger-scale wavefield and the microscale field of intermittent turbulent dissipation, both of which require many parameters for their specification? It is seen that a small modification to the Poisson vertical correlation function converts it to the corresponding correlation function of the Garrett--Munk (GM) internal wave spectral model. The linear scaling relations and vertical wavenumber dependencies of the GM model are maintained provided the Poisson constant k0 is equated with the ratio of twice the displacement variance to the vertical correlation scale of the wavefield. Awareness of this Poisson wavefield relation enables higher-order strain statistics to be determined directly from the strain spectrum. Using observations from across the Pacific Ocean, the average Thorpe scale of individual overturning events is found to be nearly equal to the inverse of k0, the metric of background thermocline distortion. If the fractional occurrence of overturning f is introduced as an additional parameter, a Poisson version of the Gregg--Henyey relationship can be derived. The Poisson constant, buoyancy frequency, and f combine to create a complete parameterization of energy transfer from internal wave scales through the Poisson subrange to dissipation. An awareness of the underlying Poisson structure of the thermocline will hopefully facilitate further improvement in both internal wave spectral models and ocean mixing parameterizations. [ABSTRACT FROM AUTHOR]

The irregular nature of vertical density profiles is a ubiquitous characteristic of the ocean thermocline. This distortion can be quantified by tracking a set of constant-density (isopycnal) surfaces over time. Examination of 30 000 km of vertical density profile data from seven Pacific Ocean sites indicates that the statistics of isopycnal vertical separation follow the gamma probability distribution, the continuous representation of a Poisson process. All aspects of this process are specified by a single parameter k0, of order 0.5-2m-1 across the Pacific. When vertical wavenumber spectra of vertical strain are nondimensionalized by k0, the variability in these pan-Pacific spectra reduce from a factor of 20 to a factor of 2. Given that numerous dimensionless metrics such as the Richardson number, Froude number, Burger number, etc., are required to specify dynamical balances in the sea, it is intriguing that a single-parameter model describes all aspects of the statistics of vertical strain over the range of scales ~2-200 m. While both internal wave and vortical motions are present in the data, the waves dominate the strain signal at these sites. The high-wavenumber cutoff in the strain spectrum is set by the nonsinusoidal waveform of short-vertical-scale internal waves. As large-scale numerical models improve in resolution, they should replicate this Poisson structure in order to properly model plankton variability, vertical diffusion, horizontal dispersion, sound propagation, and other fine-scale phenomena. [ABSTRACT FROM AUTHOR]

To clarify characteristics and mechanisms of mesoscale variability in the deep ocean, we conducted a twodimensional observation with a 3 3 3 grid mooring array around site R (308N, 1478E) during 2014-16. We analyze the obtained velocity data together with pastmooring observation data in the northwest Pacific basin and outputs of an ocean general circulation model (OGCM). In our two-dimensional mooring observations, the variability of zonal and meridional velocities at a depth of 4000m was prominent at periods of 174 and 58 days, respectively. The variability at periods of 174 and 58 days propagated to the northwest and west-southwest, respectively, as a single plane wave. The variability at the period of 58 days was considered to be topographic Rossby waves (TRWs) under stratification originated in the Kuroshio Extension region north of site R, as demonstrated by our previous study. At the period of 174 days, zonal and meridional wavenumbers estimated from the phase lag for zonal velocities also satisfied the dispersion relation of TRWs under stratification. Backward ray tracing from site R indicated that energy of TRWs propagated from the eastern slope of the Shatsky Rise to site R almost along f/H contours, where f is the Coriolis parameter and H is water depth. The orientation of major axis of variance ellipses at periods of 174 days and longer, obtained from the past mooring observations and the OGCM outputs, tended to be parallel to f/H contours, being consistent with the direction of energy propagation of TRWs. [ABSTRACT FROM AUTHOR]

Wave streaming is a near-bottom mean current induced by the bottom drag on surface gravity waves. Wave variations include the variations in wave heights, periods, and directions. Here we use numerical simulations to study the effects of wave streaming and wave variations on the circulation that is driven by incident surface waves. Wave streaming induces an inner-shelf Lagrangian overturning circulation, which links the inner shelf with the surf zone. Wave variations cause alongshore-variable wave breaking that produces surf eddies; however, such eddies can be suppressed by wave streaming. Moreover, with passive tracers we show that wave streaming and wave variations together enhance the crossshelf material transport. [ABSTRACT FROM AUTHOR]

Penetration of solar radiation in the upper few meters of the ocean creates a near-surface, stratified diurnal warm layer. Wind stress accelerates a diurnal jet in this layer. Turbulence generated at the diurnal thermocline, where the shear of the diurnal jet is concentrated, redistributes heat downward via mixing. New measurements of temperature and turbulence from fast thermistors on a surface-following platform depict the details of this sequence in both time and depth. Temporally, the sequence at a fixed depth follows a counterclockwise path in log-logN parameter space. This path also captures the evolution of buoyancy Reynolds number (a proxy for the anisotropy of the turbulence) and Ozmidov scale (a proxy for the outer vertical length scale of turbulence in the absence of the free surface). Vertically, the solar heat flux always leads to heating of fluid parcels in the upper few meters, whereas the turbulent heat flux divergence changes sign across the depth of maximum vertical temperature gradient, cooling fluid parcels above and heating fluid parcels below. In general, our measurements of fluid parcel heating or cooling rates of order 0.18Ch-1 are consistent with our estimates of heat flux divergence. In weak winds (<2ms-1), sea surface temperature (SST) is controlled by the depth-dependent absorption of solar radiation. In stronger winds, turbulent mixing controls SST. [ABSTRACT FROM AUTHOR]

Of the estimated 7117 languages in the world, approximately 1500 (21%) are indigenous to the Pacific. Despite composing approximately one-fourth of the world’s linguistic diversity, the representation of these languages in academic publication is scant, even in periodicals focused on Pacific Island studies. We investigated 34 periodicals that focus on research in Oceania. We report on (1) journal names; (2) how many are currently in circulation; (3) how many accept submissions in Indigenous Pacific languages; (4) what percent of the most recent articles were actually in Indigenous languages of the Pacific and (5) which languages those were. Five of the 34 journals allowed submissions written in Indigenous Pacific languages. Three of the five journals specified Hawaiian as an accepted language of publication; one Sāmoan and one Tahitian and any other Indigenous language of Polynesia. We were able to collect data on four of the five journals, which averaged 11% of recent publications in an Indigenous language. None accepted submissions in Indigenous languages from the Pacific outside of Polynesia.

Background and Aims Alpine oceanic ecosystems are considered amongst the most ephemeral and restricted habitats, with a biota highly vulnerable to climate changes and disturbances. As an example of an alpine insular endemic, the past and future population genetic structure and diversity, and the future distribution of Viola cheiranthifolia (Violaceae), endemic to Tenerife (Canary Islands), were estimated. The main goals were to predict distribution changes of this alpine oceanic plant under climate change, and to assist in actions for its conservation. Methods To perform population genetic analysis, 14 specific microsatellite markers and algorithms which considered the polyploid condition of V. cheiranthifolia were employed. The niche modelling approach incorporated temperature gradients, topography and snow cover maps. Models were projected into climate change scenarios to assess the extent of the altitudinal shifts of environmental suitability. Finally, simulations were performed to predict whether the environmental suitability loss will affect the genetic diversity of populations. Key Results Viola cheiranthifolia presents short dispersal capacity, moderate levels of genetic diversity and a clear population genetic structure divided into two main groups (Teide and Las Cañadas Wall), showing signs of recolonization dynamics after volcanic eruptions. Future estimates of the distribution of the study populations also showed that, despite being extremely vulnerable to climate change, the species will not lose all its potential area in the next decades. The simulations to estimate genetic diversity loss show that it is correlated to suitability loss, especially in Las Cañadas Wall. Conclusions The low dispersal capacity of V. cheiranthifolia, coupled with herbivory pressure, mainly from rabbits, will make its adaptation to future climate conditions in this fragile alpine ecosystem difficult. Conservation actions should be focused on herbivore control, population reinforcement and surveillance of niche shifts, especially in Guajara, which represents the oldest isolated population and a genetic reservoir for the species. [ABSTRACT FROM AUTHOR]

This study was carried out to estimate total catches extracted from the offshore areas of northeastern Brazil by recreational fishers from offshore operations, daily activities, and fishing competitions. It also aimed at providing a first estimate of expenditure by anglers in the region. The basis for this analysis was the data supplied by the only offshore fishing operator established in Paraíba State. The available logbooks allowed for the first estimate of total catches by anglers in Paraíba State, which was extrapolated to the entire region using information provided in a database of recreational fishers' licenses. By combining these data with catch data from fishing competitions, we were able to estimate that a peak of about 90 ton was extracted in 2011. This catch is low when compared with commercial catches, but the associated economic impacts, assessed via the expenditure by recreational fishers at US$1.5 million in 2014, is high. Moreover, catches are concentrated mainly on a small number of species, mostly Thunnus spp. and Seriola spp. in waters off Paraíba State. No information is available on the current status of these amberjacks (Seriola spp.). However, some of the snappers (Fam. Lutjanidae) included in the top species caught by recreational fishers are considered overexploited in the region. [ABSTRACT FROM AUTHOR]

Genetic population structure is often used to identify management units in exploited species, but the extent of genetic differentiation may be inflated by geographic variation in the level of hybridization between species. We identify the genetic population structure of Sebastes mentella and investigate possible introgression within the genus by analyzing 13 microsatellites in 2,562 redfish specimens sampled throughout the North Atlantic. The data support an historical divergence between the 'shallow' and 'deep' groups, beyond the Irminger Sea where they were described previously. A third group , 'slope,' has an extended distribution on the East Greenland Shelf, in addition to earlier findings on the Icelandic slope. Furthermore, S. mentella from the Northeast Arctic and Northwest Atlantic waters are genetically different populations. In both areas, interspecific introgression may influence allele frequency differences among populations. Evidence of introgression was found for almost all the identified Sebastes gene pools, but to a much lower extent than suggested earlier. Greenland waters appear to be a sympatric zone for many of the genetically independent Sebastes groups. This study illustrates that the identified groups maintain their genetic integrity in this region despite introgression. [ABSTRACT FROM AUTHOR]