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In this study, we investigate the feasibility of using historical remote sensing data to predict the future three-dimensional subsurface ocean temperature structure. We also compare the performance differences between predictive models and real-time reconstruction models. Specifically, we propose a multi-scale residual spatiotemporal window ocean (MSWO) model based on a spatiotemporal attention mechanism, to predict changes in the subsurface ocean temperature structure over the next six months using satellite remote sensing data from the past 24 months. Our results indicate that predictions made using historical remote sensing data closely approximate those made using historical in situ data. This finding suggests that satellite remote sensing data can be used to predict future ocean structures without relying on valuable in situ measurements. Compared to future predictive models, real-time three-dimensional structure reconstruction models can learn more accurate inversion features from real-time satellite remote sensing data. This work provides a new perspective for the application of artificial intelligence in oceanography for ocean structure reconstruction. [ABSTRACT FROM AUTHOR]

The Eastern Pacific Cloud Aerosol Precipitation Experiment (EPCAPE) was a year-round campaign conducted by the US Department of Energy at the Scripps Institution of Oceanography in La Jolla, CA, USA, with a focus on characterizing atmospheric processes at a coastal location. The ground-based prototype of a new Ka-, W-, and G-band (35.75, 94.88, and 238.8 GHz) profiling atmospheric radar, named CloudCube, which was developed at the Jet Propulsion Laboratory, took part in the experiment during 6 weeks in March and April 2023. This article describes the unique data sets that were obtained during the field campaign from a variety of marine clouds and light precipitation. These are, to the best of the authors' knowledge, the first observations of atmospheric clouds using simultaneous multifrequency measurements including 238.8 GHz. These data sets therefore provide an exceptional opportunity to study and analyze hydrometeors with diameters in the millimeter- and submillimeter size range that can be used to better understand cloud and precipitation structure, formation, and evolution. The data sets referenced in this article are intended to provide a complete, extensive, and high-quality collection of G-band data in the form of Doppler spectra and Doppler moments. In addition, Ka-band and W-band reflectivity and Ka-, W-, and G-band reflectivity ratio profiles are included for several cases of interest on 6 different days. The data sets can be found at https://doi.org/10.5281/zenodo.10076227 (Socuellamos et al., 2024). [ABSTRACT FROM AUTHOR]

Despite the fact that the first red tide reported on the coasts of the Iberian Peninsula was due to Lingulodinium polyedra, knowledge about their frequency and, particularly, about the environmental conditions contributing to bloom initiation is still scarce. For this reason, L. polyedra bloom episodes were observed and studied in three Galician rias during the summer season based on the 1993–2008 record database period; additionally, samples were collected in summer 2008. Proliferations of L. polyedra occurred in the rias of Ares and Barqueiro in June and August, respectively, while in the Ria of Coruña, they persisted from the end of June to early September. Red tides developed when the surface temperature reached 17 °C, with "seasonal thermal window" conditions, and when salinities were ≥30, i.e., an "optimal salinity window"; when these parameters were lower than these thresholds, cyst germination decreased. A cyst transport mechanism from sediments to the surface must also exist; this mechanism was found to be natural (tidal currents) in the ria of Barqueiro or anthropogenic (dredging) in the rias of Ares and Coruña. Surface temperatures during summer were usually favorable for cyst germination (85 to 100%) during the 1993–2008 period; however, water temperatures below 10 m depth only rarely reached the 17 °C threshold (2 to 18%). During this 16-year period, dredging activities could explain 71% (Coruña) and 44% (Ares) of the recorded bloom events. When a bloom episode developed in early summer, favorable conditions did not lead to a new red tide, probably due to the lag period required by cysts for germination. Moreover, blooms did not develop when high densities of diatoms (>1,000,000 cells·L−1) remained in the water column as a result of summer upwelling pulses occurring in specific years. The temperature–sediment disturbance pattern found in this study provides a useful tool for the prevention of eventual risks resulting from red tides of this dinoflagellate. [ABSTRACT FROM AUTHOR]

CTDs, devices that measure salinity (via conductivity), temperature, and depth in the ocean, are essential for almost all marine scientific research, whether oceanography, ecology, conservation, or management. But CTDs are often cost-prohibitive, making this essential tool of ocean science inaccessible to the majority of ocean knowledge seekers. The OpenCTD is a low-cost, open-source oceanographic instrument, built from relatively accessible components, that allows ocean knowledge seekers to collect data on salinity, temperature, and depth in waters as deep as 140 m, with depth accurate to <1 cm, temperature to ±0.1°C, and a salinity error rate of 1%, with a 90% response time of 1 second. The OpenCTD is an open, adaptable platform that allows users to integrate other sensors (e.g., dissolved oxygen, pH) to fit their specific needs or questions. The utility of the OpenCTD for both STEM education and community oceanography is demonstrated in real-world case studies. The OpenCTD offers researchers, community groups, educators, managers, and other ocean knowledge seekers the ability to collect baseline data about their local waters at a fraction of the cost of commercial alternatives and, for most use cases, with comparable data quality. [ABSTRACT FROM AUTHOR]

GEOTRACES is an international endeavor to elucidate the biogeo-chemical cycles of trace elements and their isotopes in the ocean. Inherently, this interdisciplinary program provides ample opportunities for students to develop professional, academic, and seagoing skills. This perspective recalls first-hand experiences gained from five years in the GEOTRACES community, spanning undergraduate and graduate research, including international engagement in Germany and seagoing oceanography in the South Pacific and Southern Ocean. Description of these opportunities reveals the framework that makes the GEOTRACES program a success and the culture that will ensure its ongoing legacy. [ABSTRACT FROM AUTHOR]

Since 2016, the Argo (Array for Real-Time Geostrophic Oceanography) ocean salinity data has exhibited significant drift, directly affecting the accurate quantification of the global steric sea level (SSL) rates. To further investigate how salinity drift affects the estimation of SSL rates in different depths and regions, we divide the 0–2000 m into three layers (0–300 m, 300–1000 m and 1000–2000 m) and select five open oceans (the South and North Pacific, the South and North Atlantic, and the Indian Ocean) for discussion. By comparing the SSL rates between the periods of 2005–2015 and 2005–2019, we can evaluate the impact of salinity drift. Taking the estimated results from the IPRC (provided by the International Pacific Research Center at the University of Hawaii) and BOA (provided by the Second Institute of Oceanography, China) data as examples, we find that the effect of salinity drift is the largest at the depth of 1000–2000 m, about 29% for IPRC data and about 18% for BOA data. Moreover, the South Atlantic is susceptible to the effects of salinity drift, with an approximately 13% impact for IPRC data and 21% for BOA data. [ABSTRACT FROM AUTHOR]

Ship weather routing, which involves suggesting low-emission routes, holds potential for contributing to the decarbonisation of maritime transport. However, including because of a lack of readily deployable open-source and open-language computational models, its quantitative impact has been explored only to a limited extent. As a response, the graph-search VISIR (discoVerIng Safe and effIcient Routes) model has been refactored in Python, incorporating novel features. For motor vessels, the angle of attack of waves has been considered, while for sailboats the combined effects of wind and sea currents are now accounted for. The velocity composition with currents has been refined, now encompassing leeway as well. Provided that the performance curve is available, no restrictions are imposed on the vessel type. A cartographic projection has been introduced. The graph edges are quickly screened for coast intersection via a K -dimensional tree. A least-CO 2 algorithm in the presence of dynamic graph edge weights has been implemented and validated, proving a quasi-linear computational performance. The software suite's modularity has been significantly improved, alongside a thorough validation against various benchmarks. For the visualisation of the dynamic environmental fields along the route, isochrone-bounded sectors have been introduced. The resulting VISIR-2 model has been employed in numerical experiments within the Mediterranean Sea for the entirety of 2022, utilising meteo-oceanographic analysis fields. For a 125 m long ferry, the percentage saving of overall CO 2 expenditure follows a bi-exponential distribution. Routes with a carbon dioxide saving of at least 2 % with respect to the least-distance route were found for prevailing beam or head seas. Two-digit savings, up to 49 %, were possible for about 10 d in a year. In the case of an 11 m sailboat, time savings increased with the extent of path elongation, particularly during upwind sailing. The sailboat's routes were made approximately 2.4 % faster due to optimisation, with the potential for an additional 0.8 % in savings by factoring in currents. VISIR-2 serves as an integrative model, uniting expertise from meteorology, oceanography, ocean engineering, and computer science, to evaluate the influence of ship routing on decarbonisation efforts within the shipping industry. [ABSTRACT FROM AUTHOR]

Sub-mesoscale and mesoscale (i.e., 1–10 km and 10–200 km, respectively) ocean processes are highly relevant for the understanding of global circulation, mixing of water masses and energy exchange between ocean layers. However, the processes happening at these scales are hard to be characterized using direct measurements of temperature and salinity. Direct measurements are obtained from vertical probes and/or autonomous vehicles, which, despite their high vertical resolution, are sparsely located in space and therefore unable to capture spatial details at these scales. Seismic oceanography (SO) data have been successfully used to imaging and characterize the ocean at these spatial scales. These data represent indirect measurements of the ocean temperature and salinity along kilometric transects with high horizontal resolution (i.e., a near-synaptic view of the system under investigation), but lower vertical resolution when compared with direct observations. Despite its complex oceanographic setting, the Madeira Abyssal Plain is still largely uncharacterized due to the lack of direct observations. We show for the first time a comprehensive processing, modelling and interpretation of three 2-D seismic oceanography sections from this region. The data show coherent seismic reflection in space, depth and time and shed light into this oceanographic setting with an unprecedent horizontal resolution. The SO modelling and interpretation are combined with existing direct measurements and a quantitative method to correlate thermohaline staircases interpreted from conductivity-temperature-depth casts and seismic reflections is proposed. The results show the relatively stable presence of thermohaline staircases in simultaneously time and space between 1200 and 2000 m of water depth and their spatial variability and contribute to the generalization of SO in physical oceanography. [ABSTRACT FROM AUTHOR]

Mixed Layer Depth (MLD) plays an important role in various aspects of oceanography. MLD has a characteristic parameter value that is uniform with depth. MLD has an important role for local, regional, and global phenomena. Indonesia, which is surrounded by the East Indian Ocean, will be directly influenced by the dynamics of MLD. This study aimed to analyze seasonal variability and MLD between years. Mixed layer depth data from the ARMOR3D Dataset Copernicus-Marine Environment Monitoring Service was used for MLD analysis with a threshold of 0.2°C for temperature. Wavelet analysis showed that MLD variability in the eastern Indian Ocean spans from intra-seasonal to interannual scales. Time series analysis showed a complex relationship between MLD and SST in the annual and interannual periods which indicates a different process. The MLD monthly climatology at point 90E, 0 showed the depth of mixed layers is deeper during the east monsoon (JJA-SON) ranging from 50-65 m compared to the west monsoon (DJF-MAM) which has a range of 20-40 m. Spatially the MLD in the south of the equator is deeper than in the north. Interannually, MLD is heavily influenced by the Indian Ocean Dipole. MLD depth is deeper in nIOD with a maximum depth in the range of 100 m compared to pIOD. MLD with maximum depth in the strong nIOD phase is around the equator and the pIOD phase is south of the equator. The study also showed that inter-annual variability in regions around the mainland showed a stronger response. [ABSTRACT FROM AUTHOR]

Real-time reconstruction of ocean surface currents is a challenge due to the complex, non-linear dynamics of the ocean, the small number of in situ measurements, and the spatio-temporal heterogeneity of satellite altimetry observations. To address this challenge, we introduce HIRES-CURRENTS-Net, an operational real-time convolutional neural network (CNN) model for daily ocean current reconstruction. This study focuses on the Mediterranean Sea, a region where operational models have great difficulty predicting surface currents. Notably, our model showcases higher accuracy compared to commonly used alternative methods. HIRES-CURRENTS-Net integrates high-resolution measurements from the infrared or visible spectrum—high resolution Sea Surface Temperature (SST) or chlorophyll (CHL) images—in addition to the low-resolution Sea Surface Height (SSH) maps derived from satellite altimeters. In the first stage, we apply a transfer learning method which uses a high-resolution numerical model to pre-train our CNN model on simulated SSH and SST data with synthetic clouds. The observation of System Simulation Experiments (OSSEs) offers us a sufficient training dataset with reference surface currents at very high resolution, and a model trained on this data can then be applied to real data. In the second stage, to enhance the real-time operational performance of our model over previous methods, we fine-tune the CNN model on real satellite data using a novel pseudo-labeling strategy. We validate HIRES-CURRENTS-Net on real data from drifters and demonstrate that our data-driven approach proves effective for real-time sea surface current reconstruction with potential operational applications such as ship routing. [ABSTRACT FROM AUTHOR]

We quantify an elevated occurrence of abrupt changes in ocean environmental conditions under human‐induced climate forcing using Earth system model output through a novel analysis method that compares the temporal evolution of the forcings applied with the development of local ocean state changes for temperature, oxygen concentration, and carbonate ion concentration. Through a multi‐centennial Earth system model experiment, we show that such an increase is not fully reversible after excess greenhouse gas emissions go back to zero. The increase in occurrence of regional abrupt changes in marine environmental conditions has not yet been accounted for adequately in climate impact analyses that usually associate ecosystem shifts large‐scale variability or extreme events. Estimates for remaining greenhouse gas emission targets need thus to be more conservative. Plain Language Summary: The ocean warms up, gets more acidic, and loses oxygen under progressing anthropogenic climate change putting ecosystems under stress. Regionally, abrupt changes in temperature, acidity, and dissolved oxygen concentration can occur and may make it impossible for organisms to adjust to these new environmental conditions, thereby increasing the risk for deterioration of entire ecosystems. The study provides evidence for elevated occurrence of regional abrupt changes in marine environmental conditions that is not yet accounted for appropriately in climate impact analyses that usually associate ecosystem shifts with changes in large‐scale variability or extreme events. Therefore, the time window for effective climate mitigation to prevent unwanted marine ecosystem impacts may close sooner than previously expected. Key Points: There is an elevated occurrence of abrupt changes in key ocean state variables under human‐induced climate forcingThe occurrence of abrupt changes in the upper ocean peaks around the maximum of the rate of change in human‐induced forcingA multi‐centennial legacy is expected for abrupt shifts in environmental conditions, long after a stop of anthropogenic CO2 emissions [ABSTRACT FROM AUTHOR]

Ocean heat exchanges at the marginal ice zone (MIZ) play an important role in melting sea ice. Mixed‐layer eddies transport heat and ice floes across the MIZ, facilitating the pack's access to warm waters. This study explores these frontal dynamics using disk‐shaped floes coupled to an upper‐ocean model simulating the sea ice edge. Numerical experiments reveal that small floes respond more strongly to fine‐scale ocean currents, which favors higher dispersion rates and weakens sea ice drag onto the underlying ocean. Floes with radii smaller than resolved turbulent filaments (∼2–4 km) result in a wider and more energetic MIZ, by a factor of 70% each, compared to larger floes. We hypothesize that this floe size dependency may affect sea ice break‐up by controlling oceanic energy propagation into the MIZ and modulate the sea ice pack's melt rate by regulating lateral heat transport toward the sea ice cover. Plain Language Summary: Sea ice forms as a thin layer of frozen ocean waters, which breaks into individual floes due to the action of waves, ocean currents, and atmospheric winds. At the edge of the pack, these floes are vulnerable to warm waters in the open ocean, which can favor the melt of sea ice. The transport of heat from the open ocean into ice‐covered regions is not well represented in existing climate models, notably due to their poor spatial resolution and their inability to represent the dynamics of individual floes. In this study, we use a regional numerical model to investigate how fine‐scale ocean currents (2–30 km) can help transport heat toward a sea ice pack composed of broken‐up floes. We find that this heat transport is most efficient when floes are small, because they cannot efficiently damp the mechanical energy from the surface currents and they are easily transported into the open ocean by these currents. These two processes combined may lead to sea ice melt feedbacks that are currently not captured by coarser climate models. Key Points: The sensitivity of sea ice dispersion and upper‐ocean energetics to floe size is considered at a mesoscale frontFloes smaller than turbulent filaments disperse more strongly and lead to a wider marginal ice zoneThese small floes allow for stronger eddy kinetic energy propagation and heat transport into the pack [ABSTRACT FROM AUTHOR]

SARAL/AltiKa, the first microwave altimeter operating at Ka-band frequency, recently completed nine years of operations in orbit. During these years, it has catered to many applications related to operational oceanography, climate sciences, hydrology and cryosphere. More specifically, in oceanography, SARAL has contributed immensely to operational wave and circulation modelling, eddy detection/tracking, ocean current generation and many more. However, since Feb 2019, SARAL has moved from the drifting phase (DP) to the mispointing phase (MP) due to the malfunctioning of the star sensor of the spacecraft. In this study, we analyse the instrument's performance and its waveforms during its ongoing MP. We find out that during the MP, significant wave height (SWH) measurements are anomalously high between 18 and 24 m, and wind speed measurements are between 16 and 19 m/s. In sea surface height anomaly (SSHA), there is a steady rise in negative values during the MP. In the return waveform, ∼15% degradation in Brown-type waveforms in the open ocean region is noticed. These changes significantly impact the SARAL applications. Two important applications of wave forecast and eddy detection are discussed here as examples. Following this, we also recommend using provided quality flags so that the data can be further explored for various ocean applications. [ABSTRACT FROM AUTHOR]

This article analyzes the strategic importance of hydro-politics today based on the competition between big powers in the most significative strategic maritime zones, with the aim of understanding the special geographical position of Colombia, its challenges, and opportunities, as an intermediate point of connection between North and South America and with access to the Atlantic and Pacific oceans. To take advantage of its geostrategic potential, it is suggested that the country reconnects its coastline and develops a bi-oceanic connection in Choco, as a priority hydro political imperative, to stablish a strategic maritime zone which plans and develops its geostrategic power in the current international system. [ABSTRACT FROM AUTHOR]

Scientific studies concentrated in Antarctica hold great value and importance for humanity. Research projects are conducted in various disciplines on the continent, where nearly 100 research stations from 30 countries are established. Despite the challenges posed by Antarctica's natural structure, unique environment, difficult working conditions, and limited logistics opportunities, scientific research conducted there is indispensable due to the valuable information it offers. In pursuit of accessing this information, Turkish Antarctic expeditions have been organized since 2017. In this study, a polar data center was established through a web-based geographic information system (WebGIS), a significant infrastructure for the continuity of scientific studies. The implemented projects and raw/processed data from previous expeditions in diverse subjects and disciplines, including geology, geophysics, geography, hydrology, meteorology, oceanography, glaciology, atmospheric physics, chemistry, microbiology, and remote sensing, were incorporated into this information system. Studies in Antarctica have primarily focused on observing the effects of global warming, necessitating the monitoring of past and current data related to sea ice, sea level, and coastal changes. The data also encompasses seismic, volcanic, tectonic, and Global Navigation Satellite System (GNSS) monitoring. As suggested by the Antarctic Treaty, a user-friendly website was designed and made accessible for research projects, data, and publications. An entity relationship diagram was created for the fields to be included in the database. These fields were structured as tables using structured query language (SQL) queries in PgAdmin. A workspace and storage area were created in GeoServer, and a connection was established with PostGIS. Layers of spatial and nonspatial data from the PgAdmin application were added to the GeoServer workspace. The data transferred to GeoServer were presented in an OpenLayers web map with Web Map Service (WMS) and Web Feature Service (WFS) according to Open Geospatial Consortium (OGC) standards. Additionally, a mini web map was designed using the desktop Quantum GIS (QGIS) application and GIS Cloud collaboration, displaying GNSS and meteorological (weather) observation stations on the continent. A dynamic web project was employed for coding in Eclipse software, where backend coding was done with JavaScript. SQL was used as a part of the backend to integrate data from the database per request. Frontend coding for the website's visual side was completed with HTML, CSS, and JavaScript. As a result, a WebGIS platform was developed where researchers can register, add projects, and publications, and view data on a map. Users can download, analyze, and utilize the available data. The data center's existence underscores the importance of polar science and serves as an incentive for further research. [ABSTRACT FROM AUTHOR]

Centuries of exclusion have resulted in a tangible human diversity deficit, where the diversity of oceanographers does not represent the global diversity of people impacted by ocean processes. We present six challenges faced by oceanographers who have one or more marginalized identities: (1) historical practices of conquest, discrimination, and exclusion underpin oceanography's modern diversity deficit; (2) undervalued and uncompensated labor by oceanographers from underrepresented groups can perpetuate a lack of representation by leading to burnout and attrition; (3) marginalized individuals are often forced to hide parts of their identities (languages, appearances, partners, behaviors) that deviate from outdated expectations of professionalism; (4) oceanography requires trainees to navigate extensive logistical and financial hurdles; (5) individuals from non-Western cultural and religious traditions often conceal their spiritual obligations in attempts to assimilate or avoid forgoing valuable research experiences; and (6) limited planning and transparency in oceanographic fieldwork can threaten the physical and mental safety of marginalized individuals. We highlight how holding multiple, intersecting identities can compound negative impacts on the well-being of marginalized oceanographers. Finally, we recommend solutions that individuals, mentors, professional societies, funding agencies, and institutions should undertake to move toward a more diverse oceanographic community. [ABSTRACT FROM AUTHOR]

Coral larval dispersal establishes connectivity between reefs, but larval fluxes vary over timescales from daily to multidecadal due to oceanographic variability. Using a 2‐km‐resolution ocean model, we simulate daily spawning events from 1993 to 2019 and assess the potential connectivity between all reefs in the tropical southwest Indian Ocean. Although there is a significant seasonal cycle in potential connectivity, day‐to‐day variability generally dominates. Larval dispersal pathways on any particular day provide limited information about the dispersal pathways a few days later. The magnitude of this high‐frequency variability depends on the local geography and oceanography, with small and isolated reefs generally subject to the most variability. Stochastic oceanographic variability introduces considerable uncertainty to dispersal predictions, imposing fundamental limitations on what simulations can tell us about inter‐reef connectivity. Protracted spawning over only a few days can significantly reduce variability associated with the likelihood of a larva settling. The duration of spawning is therefore a more important parameter in modeling coral connectivity than the exact timing of spawning onset. Finally, we find that a small proportion of spawning events account for the majority of settling larvae, particularly at remote islands, and demonstrate that a time‐mean picture of dispersal may be inappropriate for predicting demographic and genetic connectivity. Given the diversity of coral reef environments in the southwest Indian Ocean, we expect that these results will apply to inter‐reef coral connectivity across the tropics more broadly, as well as other weakly swimming reef taxa with the potential for long‐distance dispersal. [ABSTRACT FROM AUTHOR]

Ship weather routing, which involves suggesting low-emission routes, holds potential for contributing to the decarbonisation of maritime transport. However, its quantitative impact has been explored only to a limited extent, also for a lack of readily deployable open-source and open-language computational models. As a response, the VISIR model has been refactored in Python, incorporating new features. The velocity composition with currents has been refined, now encompassing leeway as well. For motor vessels, the angle of attack of waves has been considered, while sailboats now account for the combined effects of wind and sea currents. A least-CO2 algorithm in presence of dynamic graph edge weights has been implemented and validated, proving a quasi-linear computational performance which outperforms VISIR-1. The software suite’s modularity has been significantly improved, alongside a thorough validation against arious benchmarks. The resulting VISIR-2 model has been employed in numerical experiments within the Mediterranean Sea for the entire 2022, utilising meteo-oceanographic analysis fields. For a 125-meter-long ferry, the distribution of carbon dioxide savings follows a bi-exponential distribution. Two-digit CO2 savings were possible for more than ten days in a year. Largest savings were achieved in avoiding upwind sailing and using the lowest engine load. In the case of an 11-meter sailboat, time savings increase with the extent of path elongation, particularly during upwind sailing. The sailboat’s routes were approximately 3 % shorter thanks to optimisation, and there was potential for additional savings when favourable currents were in play. The impact of leeway was minor, but disregarding it would result in a systematic underestimation of route durations. VISIR-2 is a collaborative model with the capacity to harness knowledge from oceanography, ocean engineering, and computer science, to contribute to the decarbonisation efforts in the shipping industry. [ABSTRACT FROM AUTHOR]

The Greenland Sea is a key region for open ocean convection and ventilation, which exhibit a large variability with periods of strong convection and shutdowns. After a long period of weak winter convection (from the 1970s to the early 1990s), a recovery has been reported, beginning in the 1990s and intensifying in the early 2000s until 2013. Using ISAS, an optimal interpolation product based on Argo observations, we document a recent significant weakening of deep convection between 2014 and 2020, accompanied by a continuous warming of the mixed layer but also a freshening after 2014. These hydrographic changes likely increase the ocean stratification and precondition the shutdown of winter convection. We suggest that these property changes result from a shift of the large scale atmospheric circulation, affecting the source of Atlantic Water to the Nordic seas, causing a freshening of about −0.1 g kg−1 that spreads into the Greenland Sea. Plain Language Summary: The Greenland Sea is a key region for the climate system. There, during winter, the ocean loses heat to the atmosphere in a process called "deep convection," that results in the formation of dense water masses that ventilate and fill the deeper layers of the ocean. The Greenland Sea exhibits a high variability in the intensity of winter deep convection, but the scientific community is still debating on which processes trigger or stop convection. After a recovery period of convection, mainly in the beginning of the 21st century, convection has stopped again after 2014 and at least until 2020. Here, we suggest that this new shutdown is mainly caused by changes in the ocean upper layer temperature and salinity that increase the upper ocean buoyancy, making it more difficult to trigger deep convection during winter. We further propose that the main mechanism driving the ocean properties changes is a shift of the large scale atmospheric circulation, which affects the amount and properties of Atlantic Water transported to the Greenland Sea. Key Points: After a period of intense deep convection since 2002, convection in the Greenland Sea has weakened from 2014 to 2020The upper salinity and temperature in the months prior of convection are driving the deep convection variabilityThe upper salinity changes are resulting from changes in large scale pattern of advection [ABSTRACT FROM AUTHOR]

Understanding the transport of large ocean currents, like the Gulf Stream, has been of interest since the early days of oceanography. There has been less attention on the widths of the currents, although there exist several theoretical predictions. We present a census of time‐averaged jet profiles, using in situ and satellite data. The jets are typically asymmetrical, being narrower on the side with weaker stratification. The half‐widths Lj are correlated with the local deformation radius Ld associated with the first surface mode on either side. The dependence of Lj on Ld is predicted by simple shallow water geostrophic adjustment models, with or without outcropping layers. This implies that potential vorticity is well‐mixed adjacent to the jets, due most likely to mesoscale eddies. The findings suggest that surface jet widths are determined locally, by eddy‐mean flow interactions. Plain Language Summary: Narrow, persistent currents a few tens of kilometers wide are found in several regions of the ocean, like fast‐flowing rivers. The Gulf Stream and Kuroshio are familiar examples. We use different measurements to show that these currents have a generic shape, being asymmetric relative to their point of maximum velocity, that is, they are wider on one side and narrower on the other. The profile has a distinctive shape and results from strong eddy stirring on either side of the jet. The jet widths depend on the local density profile and on the Earth's rotation. Key Points: We present a census of the widths of several surface jets across the global ocean, using in situ and satellite dataMost jets are asymmetrical, with the half‐widths correlated with the first surface radius on each side of the jetThe asymmetry and deformation scale dependence are predicted by simple layered analytical models and reflect active lateral mixing [ABSTRACT FROM AUTHOR]

Historians of science increasingly turn to ocean spaces, especially fromthe mid-twentieth century, when oceanography adopted new strategic and economic significance during and after World War II. Yet, the overdetermination of oceanography's historiography by histories of conflict obscures the role that empire--its continuities and its ends--played in the transformation of ocean science and politics at the same time. This essay builds on recent work seeking to recover the role of empire's endurance and its long shadows in the construction of mid-twentieth-century ocean science, politics, and law. Focusing on deepsea sediments, I parse the work of H.M.S. Challenger (1872-1876) naturalist-cum-Challenger Office director John Murray alongside that of American economic geologist John Mero, who in the mid-twentieth century articulated all seabeds as storehouses of vast mineral wealth. Murray's sedimentological taxonomies and representations as well as his collected data on global oozes, nodules included, formed much of the basis for Mero's work. And, both Murray and Mero leveraged sediments to argue for proprietary positions premised on priority-in-time for resource discovery claims, and exclusive access based upon scientific knowledge and technical ability, bothmasked by tropes of equal access and opportunity. These data and practices helped Northern scientists build and maintain control over knowledge of the seabed and the value of its resources, as postcolonial and Cold War impetuses rearranged political and economic order at sea. Historicizing abyssal oozes illuminates the character of contemporary conflicts over the future of the international seabed, asking, who determines how the seabed will be valued? [ABSTRACT FROM AUTHOR]

Humpback whales Megaptera novaengliae undertake annual migrations along eastern Australia, where they can be susceptible to entanglement in set fishing gear. This can potentially result in both sublethal and fatal outcomes for the whales, and financial losses for the fishing industry, including loss of gear and catch. Interannual fluctuations in entanglement records suggest that dynamic oceanographic features may be associated with the whales' migration path, and therefore, risk of entanglement. Using records of demersal fish traps off the coast of New South Wales (NSW), we identify two areas of high fishing pressure and entanglement risk overlap. Within each area, we combine entanglement observations with metrics associated with the East Australian Current (EAC) and climate (i.e., southern oscillation index). We show that the strength and position of the EAC was associated with the likelihood of entanglement in set fishing gear. In northern NSW (30.3° S), entanglement risk was highest between July and October when the EAC is relatively close to the coast. In contrast, there was no evidence suggesting that oceanography further south in the separation zone of the EAC (33.8° S) was associated with risk of entanglement. In the years following a strongly negative SOI (i.e., El Niño events), entanglement risk was also reduced. While we provide clear linkages with regional oceanographic dynamics and entanglement risk off NSW, if a dynamic ocean management approach to reducing entanglements is to be realized, further research into the fine‐scale movements of humpback whales is needed. [ABSTRACT FROM AUTHOR]

The article explores the advantages of cooperative learning in the field of oceanography. It explains that cooperative learning, which involves structured group work, can lead to better learning outcomes and positive experiences for students. The article highlights the importance of positive interdependence and individual accountability in successful group work. It also discusses various strategies and cooperative learning structures that can be used to promote these principles, including the well-known Jigsaw technique. The article specifically focuses on the application of the Jigsaw technique in oceanography education, providing examples and practical considerations for implementation. Overall, the author emphasizes the benefits of cooperative learning in enhancing student engagement and comprehension. [Extracted from the article]

Simple Summary: The present research enriches our comprehension of the mitogenomic genetic features, genetic diversity, evolutionary past, and conservation prerequisites of Psettodes flatfishes on a global scale. This study focuses on the matrilineal evolutionary path of these primitive groups, with a specific emphasis on the complete mitogenome of the Psettodes belcheri and casting light on its genetic composition, structural traits, and evolutionary chronicle. Exploring genetic variations and phylogenetic relationships uncovers the intricate evolutionary links between Psettodes species and their broader context within the Pleuronectiformes species. The complex interplay of hydrographic conditions, ocean currents, and ecological factors emerges as pivotal in shaping the evolutionary landscape of these flatfishes. Given the potential consequences for conservation, this study highlights the necessity for a holistic comprehension of marine environments and the ramifications of climate change and human interventions on flatfish species. The mitogenomic evolution of the Psettodes flatfishes is still poorly known from their range distribution in eastern Atlantic and Indo-West Pacific Oceans. The study delves into the matrilineal evolutionary pathway of these primitive flatfishes, with a specific focus on the complete mitogenome of the Psettodes belcheri species, as determined through next-generation sequencing. The mitogenome in question spans a length of 16,747 base pairs and comprises a total of 37 genes, including 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and a control region. Notably, the mitogenome of P. belcheri exhibits a bias towards AT base pairs, with a composition of 54.15%, mirroring a similar bias observed in its close relative, Psettodes erumei, which showcases percentages of 53.07% and 53.61%. Most of the protein-coding genes commence with an ATG initiation codon, except for Cytochrome c oxidase I (COI), which initiates with a GTG codon. Additionally, four protein-coding genes commence with a TAA termination codon, while seven others exhibit incomplete termination codons. Furthermore, two protein-coding genes, namely NAD1 and NAD6, terminate with AGG and TAG stop codons, respectively. In the mitogenome of P. belcheri, the majority of transfer RNAs demonstrate the classical cloverleaf secondary structures, except for tRNA-serine, which lacks a DHU stem. Comparative analysis of conserved blocks within the control regions of two Psettodidae species unveiled that the CSB-II block extended to a length of 51 base pairs, surpassing the other blocks and encompassing highly variable sites. A comprehensive phylogenetic analysis using mitochondrial genomes (13 concatenated PCGs) categorized various Pleuronectiformes species, highlighting the basal position of the Psettodidae family and showed monophyletic clustering of Psettodes species. The approximate divergence time (35−10 MYA) between P. belcheri and P. erumei was estimated, providing insights into their separation and colonization during the early Miocene. The TimeTree analysis also estimated the divergence of two suborders, Psettodoidei and Pleuronectoidei, during the late Paleocene to early Eocene (56.87 MYA). The distribution patterns of Psettodes flatfishes were influenced by ocean currents and environmental conditions, contributing to their ecological speciation. In the face of climate change and anthropogenic activities, the conservation implications of Psettodes flatfishes are emphasized, underscoring the need for regulated harvesting and adaptive management strategies to ensure their survival in changing marine ecosystems. Overall, this study contributes to understanding the evolutionary history, genetic diversity, and conservation needs of Psettodes flatfishes globally. However, the multifaceted exploration of mitogenome and larger-scale genomic data of Psettodes flatfish will provide invaluable insights into their genetic characterization, evolutionary history, environmental adaptation, and conservation in the eastern Atlantic and Indo-West Pacific Oceans. [ABSTRACT FROM AUTHOR]

The results of seismoacoustic studies carried out in the years 2020–2023 on the shelf of southeastern Crimea by employees of the Shirshov Institute of Oceanology, Russian Academy of Sciences, using an original complex of technical means, including seismoacoustic and acoustic profilers are discussed. The data obtained made it possible to clarify the position of the paleo valleys and to provide a seismostratigraphic reference of the reflecting horizons with the identification of the main seismic complexes in the Pleistocene–Holocene part of the section. Seismic facies analysis of the wave field made it possible to clarify the paleogeographic conditions for the formation of paleo valleys. [ABSTRACT FROM AUTHOR]

The Red Sea has a special geographical feature because it is situated in the tropical and subtropical zones. The uniqueness of the Red Sea makes a variability of oceanography data (Chlorophyll-a (Chla), current, Salinity, etc.) and meteorological data (Precipitation, Wind Speed, etc.). However, investigations of differences interaction of oceanography and meteorology are less studied in of the Red Sea. Satellites and modeling make it possible to observe oceanographic and meteorological data over a long period of time. This study first demonstrates that there are three major areas along the Red Sea that represent the different Chl-a concentrations during the rainy season. The month of July has the highest Chl-a concentration in the south (1.3 mg/m³) and the lowest Chl-a concentration in the north (0.18 mg/m³). The southern part of the Red Sea has a different generation mechanism from the northern part of the Red Sea in terms of increasing and decreasing Chl-a concentrations. The existence of surface runoff in this area may result in the supply of anthropogenic organic compounds and fresh water to coastal waters. This may increase the supply of nutrients at the peak of the rainy season, and finally increase the concentration of Chl-a in the southern part. In the middle part, the variability of Chl-a is mainly affected by wind speed. Meanwhile, the high salinity in the northern part may limit the growth of phytoplankton and keep the Chl-a concentration low. [ABSTRACT FROM AUTHOR]

Over a hundred experiments were conducted between 1998 and 2022 in the Mediterranean Sea using surface Lagrangian drifters at coastal and offshore levels. Raw data were initially unified and pre-processed manually by eliminating spikes and wrong positions or date/time information. The integrity of the received data packages was checked, and incomplete ones were discarded. Deployment information was retrieved for each drifter and integrated into the PostgreSQL database, realized and maintained by the National Institute of Oceanography and Applied Geophysics (OGS) in Trieste (Italy). This database also collects a variety of metadata about the drifter model, project, owner, and operator. Subsequently, data were processed using standard procedures of editing and quality control developed for the OGS drifter dataset to remove spikes generated by malfunctioning of the sensors and to obtain files with common characteristics. Drifter data and plots of each track were also visually checked to remove any point not identified by the automatic procedure and which were clearly erroneous. Drifter trajectories were split into two or more segments that are considered different deployments in the case of specific drifter behaviour. Data were interpolated at defined time intervals providing a dataset of 158 trajectories, available from the public open-access repository of SEA scieNtific Open data Edition (SEANOE) at 10.17882/90537 (Ribotti et al., 2022), in two versions (one compliant with the Copernicus format and the other one usable with Panoply netCDF viewer), and of SeaDataNet at https://cdi.seadatanet.org/search/welcome.php?query=2610&query%5fcode={9F00DF80-1881-42DD-9DF1-B9BD0282F2B0} (last access: 5 October 2023). [ABSTRACT FROM AUTHOR]

Harmful algal blooms (HABs) are increasing globally, causing economic, human health, and ecosystem harm. In spite of the frequent occurrence of HABs, the mechanisms responsible for their exceptionally high biomass remain imperfectly understood. A 50-y- old hypothesis posits that some dense blooms derive from dinoflagellate motility: organisms swim upward during the day to photosynthesize and downward at night to access deep nutrients. This allows dinoflagellates to outgrow their nonmotile competitors. We tested this hypothesis with in situ data from an autonomous, ocean-wave- powered vertical profiling system. We showed that the dinoflagellate Lingulodinium polyedra’s vertical migration led to depletion of deep nitrate during a 2020 red tide HAB event. Downward migration began at dusk, with the maximum migration depth determined by local nitrate concentrations. Losses of nitrate at depth were balanced by proportional increases in phytoplankton chlorophyll concentrations and suspended particle load, conclusively linking vertical migration to the access and assimilation of deep nitrate in the ocean environment. Vertical migration during the red tide created anomalous biogeochemical conditions compared to 70 y of climatological data, demonstrating the capacity of these events to temporarily reshape the coastal ocean’s ecosystem and biogeochemistry. Advances in the understanding of the physiological, behavioral, and metabolic dynamics of HAB-forming organisms from cutting-edge observational techniques will improve our ability to forecast HABs and mitigate their consequences in the future. [ABSTRACT FROM AUTHOR]

Since the launch of CFOSAT on 29 October 2018, more than three years of observational data of ocean wave spectra with a frequency range of 0.02–0.26 Hz and a horizontal resolution of 70–90 km have been obtained. This study compares wave spectra retrieved from 6°, 8°, and 10° incidence angle beams and their combination provided by CFOSAT with corresponding data from 98 buoys from the National Data Buoy Center (NDBC) in order to validate the remote sensing wave spectral accuracy from 1 January 2020 to 31 December 2022. The correlation coefficient of frequency spectra (Rs) between CFOSAT and buoys is used to represent the accuracy of the spectral form; the root mean square (RMS) of the significant wave height (SWH) is used to represent the accuracy of the total energy. The results indicate that CFOSAT can retrieve reliable wave frequency spectral forms with a high significant wave height (Rs > 0.8 when SWH > 3 m; RS < 0.4 when SWH < 1 m). The low-frequency noise in the swell part causes the main error, the RMS of the swell height is 0.4 m whereas the RMS of wind wave height is 0.24 m, and the mask filter used for spectral partitioned provided by CFOSAT can eliminate the low-frequency noise and improve the Rs of 10° beam wave spectra from 0.59 to 0.64. For the wind wave spectra, the correct spectra have been achieved and the mask filter cannot improve the accuracy. The wave spectra from the 10° beam without mask filtering provides the best estimation of total energy, the RMS of SWH is 0.23 m, after the mask filtering, the best estimation of spectral form can be achieved, the Rs is 0.64. The novelty of this study is that we found the strong correlation between SWH and Rs, where the scatter of SWH and Rs can be fitted as: Rs = 1 − exp(−0.89·SWH + 0.20); according to this approximate formula, we can estimate the reliability of wave spectra provided by CFOSAT according to the SWH in any region, which is important for wave spectral assimilation in the numerical model. The validation of wave direction indicates that the accuracy of wave spectra in the directional component is poor; further research is needed on the causes of directional errors. Generally, this study is not only an evaluation of the quality of the CFOSAT spectral data, but also an important reference for a series of research requiring the CFOSAT spectral data. [ABSTRACT FROM AUTHOR]

In the last decade, an enormous amount of georeferenced oceanographic data, co-located with catch information, have been collected through the use of commercial fishing vessels operating in the Adriatic Sea and belonging to the fleet monitored by the AdriFOOS (Adriatic Fishery and Oceanography Observing System) infrastructure. This document describes the dataset of depth (pressure) and temperature profiles collected by means of AdriFOOS in the period 2012–2020 (available at 10.17882/73008, Penna et al., 2020) and briefly illustrates the structure of this facility, the oceanographic dataset validation procedures, and some of the results achieved, and it also lists some possible operational applications. This information is of the utmost importance to provide data to feed oceanographic models and advance knowledge on climate change, as well as to improve the ecosystem approach to fishery management. [ABSTRACT FROM AUTHOR]

Sea surface winds and waves are very important phenomena that exist in the air–sea boundary layer. With the advent of climate change, cascade effects are bringing more attention to these phenomena as warmer sea surface temperatures bring about stronger winds, thereby altering global wave conditions. Synthetic aperture radar (SAR) is a powerful sensor for high-resolution surface wind and wave observations and has accumulated large quantities of data. Furthermore, deep learning methods have been increasingly utilized in geoscience, especially the inversion of ocean information from SAR imagery. Here, we propose a method to invert various parameters of ocean surface winds and waves using Sentinel-1 SAR IW mode data. To ensure this method is more robust and scalable, we augmented the input data with dual-polarized SAR imagery, an incident angle, and a more constrained homogeneity test. This method adopts a deeper structure in order to retrieve more wind and wave parameters, and the use of residual networks can accelerate training convergence and improve regression accuracy. Using 1600 training samples filtered by a novel homogeneity test and with significant wave heights between 0 and 10 m, results from error parameters including the root mean square error (RMSE), scatter index (SI), and correlation coefficient (COR) show the great performance of this proposed method. The RMSE is 0.45 m, 0.76 s, and 1.90 m/s for the significant wave height, mean wave period, and wind speed, respectively. Furthermore, the temporal variation and spatial distribution of the estimates are consistent with China–France Oceanography Satellite (CFOSAT) observations, buoy measurements, WaveWatch3 regional model data, and ERA5 reanalysis data. [ABSTRACT FROM AUTHOR]

Predicting recruitment in a reliable fashion is a great challenge within operational fisheries advice. Here, we consulted the unique but undercommunicated IMR Cod Larva Project (1975–1990), its spin-offs, placed in an international era of advancements over the last 50 years to glance into the future. Few initiatives of this kind have applied such extensive research approaches, spanning from laboratory, mesocosm, tank, and field studies to process modelling. The "critical period" concept appeared misleading, covering months rather than days of the early life history stages (ELHS) of Northeast Arctic cod. Larval feeding success was strongly modified by improved encounter rates from wind-induced turbulence. In addition, the following maternal effect studies evidenced that the dynamics of stock demography prior to spawning should be upheld to promote recruitment success. Although we now have lower-trophic level models as well as ELHS individual-based models, such models are still insufficiently reflecting the needed spatiotemporal resolution. The same problem applies to climate/circulation models. Nevertheless, this long-lasting research has significantly improved the mechanistic understanding of ELHS dynamics but also of the more predictable adult reproductive parameters. Based on a "to-list list," we suggest research avenues that should be pursued to further improve our ability predicting recruitment strength in marine fish stocks. [ABSTRACT FROM AUTHOR]

Coastal water level measurements represent one of the earliest geophysical measurements and allow an assessment of historical sea level rise and trends in tides, river flow and storm surge. However, recovery and digitization of archival tidal records have been much less widespread and systematic than, for example meteorological records. In this contribution, we discuss data rescue efforts and lessons learned in France, the United States and the United Kingdom, countries with early and extensive tide gauge networks by the mid‐19th century. We highlight the importance of (a) cataloguing the historical gauge records, as a first step towards locating them; (b) locating data in archives, and then recovering and saving data by any means necessary, including photographs and scanning; (c) obtaining metadata, including both quantitative survey records, gauge checks and clock data, but also qualitative records such as gauge notes, letters and reports; and (d) quantitative statistical analysis of data and datum quality, using both standard data‐entry checks but also tools that leverage the unique predictability of tide measurements. Methods for digitizing original analogue records are also discussed, including semi‐automatic, computer‐based methods of digitizing tidal charts (marigrams). Although the current best practice is described, future improvements are desirable and needed to make the more than estimated 10,000 station years of unused, undigitized records available to the scientific community. [ABSTRACT FROM AUTHOR]

This document provides an overview of research conducted by Croatian scientists in the field of physical oceanography from 2019 to 2022. The research covered a wide range of topics and utilized various equipment and measurement techniques. The studies provided valuable insights into the physical properties of the sea, climate change impacts, and the behavior of oceanic processes. The document includes a list of scientific articles and publications related to these studies, which can be useful for library patrons conducting research on these topics. [Extracted from the article]

Bringing together research on human impacts on marine environments, cultural representation, and geographic information systems (GIS), we explore new approaches to digitally representing the anthropogenic ocean. Marine environments present vexing subjects to capture digitally. Complex physical and biological oceanography, invisible boundaries, ambiguous legal controls, conflicts between multiple stakeholders over subsistence and commercial marine resources, and cultural variations in core ocean epistemologies complicate our ability to model historical and contemporary human interactions with the marine environment. Academic focus on the concept of the Anthropocene within geography, together with critical GIS studies, open new possibilities to transcend division between natural and social sciences. We propose an object-oriented, multiscalar framework for a database of anthropogenic ocean layers that represent human-ocean interactions. We outline strategies for digitally representing human experiences of maritime space and introduce a prototype GIS data structure for its delivery. [ABSTRACT FROM AUTHOR]

Due to its maneuverability and agility, the shipborne high-frequency surface wave radar (HFSWR) provides a new way of monitoring large-area marine dynamics and environment information. However, wind direction ambiguity is problematic when using monostatic shipborne HFSWR for wind direction inversion. In this article, an unambiguous wind direction measurement method based on wind direction interval limitation is proposed. The two first-order spectral wind direction estimation methods are first presented using the relationship between the normalized amplitude differences or ratios of the broadened Doppler spectrum and the wind direction. Moreover, based on the characteristic of a small wind direction estimation error in a large included angle between the spectral wind direction and the radar beam, the wind direction interval is obtained by counting the distribution of radar-measured wind direction within this included angle. Furthermore, the eliminated ambiguity of wind direction is transformed to judge the relationship between the wind direction interval and the two curves, which represent the relationship between the spreading parameter and the wind direction. Therefore, the remote sensing monitoring of ocean surface wind direction fields can be realized by shipborne HFSWR. The simulation results are used to evaluate the performance of the proposed method and the multi-beam sampling method for wind direction inversion. The experimental results show that the errors of wind direction estimated by the multi-beam sampling method and the equivalent dual-station model are large, and the proposed method can improve the accuracy of wind direction measurement. Three widely used wave directional spreading models have been applied for performance comparison. The wind direction field measured by the proposed method under a modified cosine model agrees well with that observed by the China-France Oceanography Satellite (CFOSAT). [ABSTRACT FROM AUTHOR]

The dinoflagellate lineage Syndiniales currently consists entirely of parasitic species that fall into five well‐supported clades. Environmental sequencing studies worldwide have found an abundance of Syndiniales in a variety of marine ecosystems, but very little is known about the majority of Syndiniales species including two entire clades which have only been observed in sequence data. Syndiniales are known to have a wide range of hosts, but only a few dozen interactions have been confirmed through observation of actual infections. Here, we describe the diversity of Syndiniales found at the Scripps Institution of Oceanography pier over the course of a year based on 18S sequencing. We find Syndiniales to be the most species (amplicon sequence variant)‐rich taxonomic group and for its members to be present and abundant throughout the year. We used several analytical techniques to identify potential parasite–host interactions which we were then able to visualize over time. Using mock communities and size fractionation of seawater, we suggest that the majority of Syndiniales sequences that are found in environmental studies belong to the free‐living dinospore stage rather than representing active infections. [ABSTRACT FROM AUTHOR]

• High-accuracy dynamic modeling is proposed for the ocean temperature field forecast. • Incremental data learning is developed for solving the continuous observation process. • The proposed method can disentanglement the dynamic and stable features. With the development of sensor technology, data-driven modeling methods for physical oceanography have boomed. Existing deep learning studies lack interpretability from the physical mechanisms. This paper proposes a novel feature disentanglement learning model for the ocean temperature field forecast. In this method, feature disentanglement is adopted to decompose the high-dimensional measured temperature information based on Tucker decomposition. The extracted dynamic feature is filtered and predicted by incremental dynamic learning, and the incremental data information is balanced by maximizing the Gaussian likelihood. Then, the dynamic feature can be entangled with the stable features to predict the ocean temperature field. Last, incremental residual learning can compensate for the feature disentanglement learning error. Experiments on the temperature dataset of the Western Pacific have verified that the proposed method is superior to the existing baselines. [ABSTRACT FROM AUTHOR]

The commercial Dungeness crab (Metacarcinus magister) fishery in Oregon and Washington (USA) is one of the most valuable fisheries in the region, but it experiences high interannual variability. These fluctuations have been attributed to environmental drivers on seasonal and annual timescales. In this study, researchers and state and tribal fisheries managers develop a statistical model for Dungeness crab catch per unit effort (CPUE) to help inform dynamic management decisions in Oregon and Washington. Fishing observations were matched to seasonally forecast and lagged ocean conditions from J-SCOPE, a regional forecast system (http://www.nanoos.org/products/j-scope/). Inclusion of dynamic and lagged ocean conditions improved model skill compared to simpler models, and the best model captured intraseasonal trends and interannual variability in catch rates, and spatial catch patterns. We also found that model skill relied on fishing behaviour, which varies interannually, highlighting the need for advanced fishing behaviour modelling to reduce uncertainty. The relationships between catch rates and ocean conditions may help elucidate environmental influences of catch variability. Forecast products were co-designed with managers to meet their needs for key decision points. Our results illustrate a seasonal forecasting approach for management of other highly productive, but also dynamic, invertebrates that increasingly contribute to global fisheries yield. [ABSTRACT FROM AUTHOR]

The significance of fluid transport in the ocean due to migrating aggregations of zooplankton remains poorly understood due to practical challenges associated with predicting, identifying, and quantifying instances of enhanced biogenic mixing. We present a new approach to overcome these limitations by quantifying the biogenic transport via its distinct magnetic signatures. This present approach can be accomplished potentially without a priori knowledge of the precise location of the aggregation and without triggering animal avoidance caused by the introduction of instruments into the migration. Plain Language Summary: Fluid transport by vertically migrating aggregations of plankton has long been explored as a potentially important source of ocean mixing. However, direct evidence of enhanced stirring remains inconclusive as current approaches require a priori knowledge of the precise aggregation location and typically trigger animal avoidance behavior from introducing instrumentation into the migration. This Letter proposes a new approach to overcome these longstanding limitations by measuring the magnetic signatures of biogenic transport. By leveraging modern magnetometry, especially quantum‐enhanced techniques, magnetic measurements of biogenic stirring can be related to the integrated fluid flow and are potentially detectable remotely at distances far removed from the aggregation. Key Points: Fluid transported and mixed by vertically migrating aggregations of plankton in the ocean has a distinct magnetic field signatureThe magnetic signature of biomixing is potentially detectable far from aggregations with emerging, quantum‐enhanced magnetometry techniquesThe present approach avoids triggering animal avoidance behavior and does not require a priori knowledge of the precise aggregation location [ABSTRACT FROM AUTHOR]

Professional and scientific societies are increasingly engaging in efforts to create a science community that manifests justice, equity, diversity, and inclusion (JEDI). However, progress assessment is challenging, and opportunities for community feedback are limited. During the 2022 Ocean Sciences Meeting, the Oceanography Society (TOS) JEDI committee led an interactive Town Hall to collect feedback from conference participants and TOS membership on three themes: challenges, initiatives, and opportunities related to advancing JEDI in ocean sciences. This Town Hall was preceded by a survey that was administered to the TOS membership. Survey respondents and Town Hall participants provided valuable observations and synthesis on the past, present, and future of JEDI work in ocean sciences. Discussion included both positive efforts and outcomes of JEDI work as well as harmful and ineffective practices. This paper synthesizes feedback received and highlights ways in which the ocean sciences community and professional and scientific societies can advance similar work. Gatekeeping, a system of implicit or explicit cultural and institutional constraints to and requirements for entry into a field, was identified as the most significant challenge to diversifying the ocean sciences. The majority of survey respondents agreed that efforts to broaden participation have been successful, and identified specific initiatives that have been effective, including the development and support of mentorship and training programs and partnerships with minority-serving institutions. Some challenges to advancing JEDI initiatives include targeted recruitment from the most "elite" institutions and "parachute science." Respondents agreed that professional and scientific societies have an important role to play in advancing JEDI in ocean sciences. Participants discussed strategies to broaden participation, including efforts that can be employed by professional and scientific societies such as regular data collection on demographics, improved information sharing, and stricter codes of conduct at professional meetings. We conclude by summarizing some new TOS-led initiatives that are designed to promote JEDI in ocean sciences and beyond. [ABSTRACT FROM AUTHOR]

The Blue Economy, which is based on the sustainable use of the ocean, is demanding better understanding of marine ecosystems, which provide assets, goods, and services. Such understanding requires the use of modern exploration technologies, including unmanned underwater vehicles, in order to acquire quality information for decision-making processes. This paper addresses the design process for an underwater glider, to be used in oceanographic research, that was inspired by leatherback sea turtles (Dermochelys coriacea), which are known to have a superior diving ability and enhanced hydrodynamic performance. The design process combines elements from Systems Engineering and bioinspired design approaches. The conceptual and preliminary design stages are first described, and they allowed mapping the user's requirements into engineering characteristics, using quality function deployment to generate the functional architecture, which later facilitated the integration of the components and subsystems. Then, we emphasize the shell's bioinspired hydrodynamic design and provide the design solution for the desired vehicle's specifications. The bioinspired shell yielded a lift coefficient increase due to the effect of ridges and a decrease in the drag coefficient at low angles of attack. This led to a greater lift-to-drag ratio, a desirable condition for underwater gliders, since we obtained a greater lift while producing less drag than the shape without longitudinal ridges. [ABSTRACT FROM AUTHOR]

The offshore waters of China are a typical monsoon−affected area where the significant wave height (SWH) is strongly influenced by the different seasonal mean flow in winter and summer. However, limited in situ validations of the SWH have been performed on the China–France Oceanography Satellite (CFOSAT) in these waters. This study focused on validating CFOSAT nadir SWH data with SWH data from in situ buoy observations for China's offshore waters and the Haiyang−2B (HY−2B) satellite, from July 2019 to December 2021. The validation against the buoy data showed that the relative absolute error has a seasonal cycle, varying in a narrow range near 35%. The RMSE of the CFOSAT nadir SWH was 0.29 m when compared against in situ observations, and CFOSAT was found to be more likely to overestimate the SWH under calm sea conditions. The sea−surface winds play a key role in calm sea conditions. The spatial distributions of the CFOSAT and HY−2B seasonal SWHs were similar, with a two−year mean SWH−field correlation coefficient of 0.98. Moreover, the coherence between the two satellites' SWH variance increased with SWH magnitude. Our study indicates that, in such typical monsoon−influenced waters, attention should be given to the influence of sea conditions on the accuracy of CFOSAT SWH, particularly in studies that combine data from multiple, long−duration space−based sensors. [ABSTRACT FROM AUTHOR]

The wave spectrometer operated by the China–France Oceanography Satellite (CFOSAT) can provide global ocean wave observation data. Although a lot of work on calibration and verification has been carried out in the open oceans dominated by swells, the quality of the data in the relatively enclosed sea area with complex terrain still lacks sufficient examination. The objective of this study is to assess the performance of the significant wave height data of the CFOSAT in the South China Sea (SCS), a unique sea area characterized by semi-enclosed basin and multi-reef terrain, and to recognize the environmental factors affecting the data quality. Compared against the long-term observations from five mooring or buoy sites, we find that the data is well performed in the relatively open and deep areas of the SCS, with an average correlation coefficient as high as 0.87, and a low average root-mean-square error of 0.47 m. However, the combined effects of complex topography, monsoons, and swell proportion variation will affect the performance of data. In the southern deep areas, the waves may be affected by a large number of dotted reefs, leading to wave deformations and energy dissipation in different seasons. In the northern nearshore areas, waves tend to be sheltered by the land or distorted by the shallow topography effects. These processes make it difficult for the swell to fully develop as in the open oceans. The low proportion of swell is a disadvantage for the CFOSAT to correctly observe the wave data and may lead to possible errors. Our results emphasize the importance of more verification when applying the CFOSAT data in certain local seas, and the necessity to adjust the algorithm of inverting wave spectra according to specific environmental factors. [ABSTRACT FROM AUTHOR]

Cyanophages exert important top-down controls on their cyanobacteria hosts; however, concurrent analysis of both phage and host populations is needed to better assess phage–host interaction models. We analyzed picocyanobacteria Prochlorococcus and Synechococcus and T4-like cyanophage communities in Pacific Ocean surface waters using five years of monthly viral and cellular fraction metagenomes. Cyanophage communities contained thousands of mostly low-abundance (<2% relative abundance) species with varying temporal dynamics, categorized as seasonally recurring or non-seasonal and occurring persistently, occasionally, or sporadically (detected in ≥85%, 15-85%, or <15% of samples, respectively). Viromes contained mostly seasonal and persistent phages (~40% each), while cellular fraction metagenomes had mostly sporadic species (~50%), reflecting that these sample sets capture different steps of the infection cycle—virions from prior infections or within currently infected cells, respectively. Two groups of seasonal phages correlated to Synechococcus or Prochlorococcus were abundant in spring/summer or fall/winter, respectively. Cyanophages likely have a strong influence on the host community structure, as their communities explained up to 32% of host community variation. These results support how both seasonally recurrent and apparent stochastic processes, likely determined by host availability and different host-range strategies among phages, are critical to phage–host interactions and dynamics, consistent with both the Kill-the-Winner and the Bank models. [ABSTRACT FROM AUTHOR]

The French coast of the Eastern English Channel (ECC) is classified as potential eutrophication zone by the Paris and Oslo Convention (OSPAR), and as moderate to poor according to phytoplankton quality element of the Water Framework Directive (WFD). Indeed, the French part of the EEC is regularly affected by Phaeocystis globosa bloom events, which have detrimental effects on the marine ecosystem, economy as well as public health. Since phytoplankton is an important indicator of water quality, the MAREL Carnot oceanographic multi-sensor station was installed in the Eastern English Channel at the Carnot wall in Boulogne sur Mer in 2004. The aim of this station was to monitor water quality and phytoplankton in order to complement results from existing more conventional low resolution monitoring programs, with high frequency data (sampling every 20 minutes). The purpose of this paper is to introduce the MAREL Carnot dataset and show how it can be used for several research objectives. MAREL Carnot collects high frequency, multi-parameter observations from surface water, as well as meteorological measurements, and send data almost immediately to an inshore data center. In this paper, we present several physiochemical and biological parameters measured by this station. In addition, we demonstrated, based on previous research activities, that the MAREL Carnot dataset is useful for evaluating environmental or ecological statuses, marine phytoplankton ecology, physical oceanography, turbulence, as well as public policy. Most importantly, we showed its contribution to Marine Strategy Framework Directive (MSFD) and other regional or universal conventions. [ABSTRACT FROM AUTHOR]

High-resolution models have become widely available for the study of the ocean's small-scale processes. Although these models simulate more turbulent ocean dynamics and reduce uncertainties of parameterizations, they are not practical for long-term simulations, especially for climate studies. Besides scientific research, there are also growing needs from key applications for multi-resolution, flexible modeling capabilities. In this study we introduce the Ocean Modeling with Adaptive REsolution (OMARE), which is based on refactoring Nucleus for European Modelling of the Ocean (NEMO) with the parallel computing framework of JASMIN (J parallel Adaptive Structured Mesh applications INfrastructure). OMARE supports adaptive mesh refinement (AMR) for the simulation of the multi-scale ocean processes with improved computability. We construct an idealized, double-gyre test case, which simulates a western-boundary current system with seasonally changing atmospheric forcings. This paper (Part 1) focuses on the ocean physics simulated by OMARE at two refinement scenarios: (1) 0.5–0.1 ∘ static refinement and the transition from laminar to turbulent, eddy-rich ocean, and (2) the short-term 0.1–0.02 ∘ AMR experiments, which focus on submesoscale processes. Specifically, for the first scenario, we show that the ocean dynamics on the refined, 0.1 ∘ region is sensitive to the choice of refinement region within the low-resolution, 0.5 ∘ basin. Furthermore, for the refinement to 0.02 ∘ , we adopt refinement criteria for AMR based on surface velocity and vorticity. Results show that temporally changing features at the ocean's mesoscale, as well as submesoscale process and its seasonality, are captured well through AMR. Related topics and future plans of OMARE, including the upscaling of small-scale processes with AMR, are further discussed for further oceanography studies and applications. [ABSTRACT FROM AUTHOR]

Biofouling is the major factor that limits long-term monitoring studies with automated optical instruments. Protection of the sensing areas, surfaces, and structural housing of the sensors must be considered to deliver reliable data without the need for cleaning or maintenance. In this work, we present the design and field validation of different techniques for biofouling protection based on different housing materials, biocides, and transparent coatings. Six optical turbidity probes were built using polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), PLA with copper filament, ABS coated with PDMS, ABS coated with epoxy and ABS assembled with a system for in situ chlorine production. The probes were deployed in the sea for 48 days and their anti-biofouling efficiency was evaluated using the results of the field experiment, visual inspections, and calibration signal loss after the tests. The PLA and ABS were used as samplers without fouling protection. The probe with chlorine production outperformed the other techniques, providing reliable data during the in situ experiment. The copper probe had lower performance but still retarded the biological growth. The techniques based on transparent coatings, epoxy, and PDMS did not prevent biofilm formation and suffered mostly from micro-biofouling. [ABSTRACT FROM AUTHOR]