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It is hard not to consider sea-level rise as reflective of an imminent crisis. Drawing together insights from Black feminism and Indigenous thought from the Island Pacific, this article counters a discourse of crisis without uncritically accepting the "oceanifying" of the planet. It moves between analyses of poetic, visual, and plant cultivation practices to show that there is a rubric for living and thinking with the ocean that emphasizes how human and nonhuman life can "become-with" each other in response to ecological degradation while still grappling with the lived legacies of colonial pasts. These oceanic coordinations are ways of knowing that destabilize human exceptionalism from the outset while not excluding the human entirely. Rather, these frameworks incorporate human-nonhuman relations to expand our frame of reference, challenging dominant anthropocentric narratives of crisis and helping imagine and live within oceanic futures. [ABSTRACT FROM AUTHOR]

The spot (Leistomus xanthurus) is among the most abundant demersal fish species in the estuaries of the Atlantic and Gulf coasts of the United States and in the coastal ocean. [...]

When it comes to telling ocean conservation stories, science provides the foundation, but photography brings them to life. That's the perspective that conservationist and award-winning photographer Henley Spiers brings to [...]

Based on reanalysis data and numerical model, this study documented an unusually weak southward Somali Current (SSC) circulation, an anticlockwise circulation in the western Arabian Sea, during the winter of 1997 to spring 1998, throughout the two-decade period from 1994 to 2017. Theoretical analysis and model simulations suggest that the exceptionally weak SSC circulation was primarily caused by abnormal wind forcing around the equator, associated with extreme climate events. The strong equatorial easterly anomalies are mainly responsible for the weakening of the SSC circulation north of ∼6°N and contribute to about half of the weakening south of ∼6°N, by regulating the layer thickness along the eastern boundary, following the time-dependent Sverdrup relation. The large negative wind stress curl anomalies near the equator contribute to another half of the weakening south of ∼6°N. This research underscores the dynamic connection between the circulation in the western basin and equatorial dynamics during extreme climate modes. Significance Statement: The dynamic linkage between the western basin circulation and the equatorial forcing remains elusive. Based on reanalysis data, theoretical analysis, and numerical simulations, this study has confirmed that the exceptionally weak southward Somali Current circulation during the winter of 1997 to spring 1998 was significantly influenced by abnormal wind patterns around the equator, triggered by extreme climate modes. [ABSTRACT FROM AUTHOR]

Validating satellite data using buoys presents a significant challenge due to the differing spatial and temporal representativeness of these data sources. This discrepancy introduces two critical issues in satellite data validation: the selection of the matchup window during the collocation process and the estimation of representativeness error. While numerous studies have addressed these issues independently, research on their interaction remains limited. Utilizing quadruple Sea Surface Salinity (SSS) matchup datasets, this study investigates the impact of the time window on the estimation of SSS representativeness error between two satellite observations: SMOS and SMAP. Our results reveal a clear dependence of representativeness error on the selected time windows. In the global ocean, the variance of representativeness errors within a small time window is 0.040 psu2, which is substantially greater than that of the entire dataset (0.016 psu2). In contrast, the representativeness errors within larger time windows are systematically lower than those within smaller time windows. This research also finds that this dependency is not influenced by the randomness of the matchup data, climatological Sea Surface Salinity, or geographic locations. Instead, our findings suggest that the impact of the time window on representativeness error may reflect the characteristics of satellite data across different time intervals. Satellites are more likely to capture SSS signals within smaller time windows, resulting in larger representativeness errors when comparing satellite SSS with buoy measurements. Conversely, larger time windows lead to significant mismatches between satellite observations and hinder the ability of satellites to detect SSS signals, which can result in smaller or even reversed representativeness errors. [ABSTRACT FROM AUTHOR]

In the context of rapidly rising sea levels over the north Indian Ocean, the decadal variations play significant role and predicting them is of utmost important to the society. The present study evaluates the quality of all the available retrospective decadal sea level predictions from the state-of-the-art climate models of the Coupled Model Intercomparison Project (CMIP) Phase 6 (CMIP6). The models are skilful in predicting the sea level over the tropical Indo-Pacific for the lead year 1 and thereafter the skill persists mainly over the western Indian Ocean regions. Most of the models exhibit significant skill in the Arabian Sea region at higher leads including 2–5 years and 6–9 years. Half of the models display higher sea level prediction skill over the Arabian Sea at lead year 2–5, compared to lead year 1. Taking into account of the close association between the Indian Ocean decadal sea level variations and the decadal climate variability in the Pacific and Atlantic, the skill of models in predicting the Pacific Decadal Oscillation (PDO) and Atlantic Multidecadal Oscillation (AMO) up to a decade is also assessed in this study. The AMO is better predicted in most of the models up to lead year 9, whereas only few models display skill in predicting the PDO. Skilful representations of strong cross equatorial flow and convergence of southerly winds towards the Arabian Sea region are noted in the CMIP6 predictions, which are responsible for better sea level prediction skill over the Arabian Sea. This study highlights that the better representation of AMO in the models has primarily contributed to the skilful sea level predictions over the Arabian Sea region. [ABSTRACT FROM AUTHOR]

The Indian Ocean dipole (IOD) is a prominent interannual phenomenon in the tropical Indian Ocean (TIO), influencing weather and climate globally, particularly during extreme IOD events. The IOD shows notable amplitude asymmetry in both observations and historical simulations from the phase 6 of Coupled Model Intercomparison Project (CMIP6), with positive events having a greater magnitude than negative events, mainly due to the negative nonlinear dynamical heating. However, simulations under the shared socioeconomic pathway 5-8.5 (SSP5-8.5) scenario indicate a notable reduction in IOD asymmetry. It shows that this reduction points to an increased frequency of extreme negative IOD events under global warming. The primary cause of this reduced IOD asymmetry is less negative nonlinear dynamical heating in future simulations, especially the nonlinear zonal advection. Under global warming, the increased atmospheric static stability weakens the large-scale atmospheric response to sea surface temperature (SST) anomalies forcing. This leads to reduced strength of nonlinear zonal advection, resulting in a decreased IOD asymmetry. Nevertheless, nonlinear vertical advection, another key factor in IOD asymmetry, remains comparable due to the increased upper-ocean stratification in the eastern TIO. The reduced inhibition of negative nonlinear zonal advection and the increased SST response to deepening thermocline contribute to the increased frequency of extreme negative IOD events. These changes underscore the potential risks associated with negative IOD events in a warming world, emphasizing the importance of understanding IOD dynamics for improved climate impact prediction and future preparedness. [ABSTRACT FROM AUTHOR]

Ongoing research is focused on underwater wireless sensor networks (UWSNs), which hold great promise for various applications to improve human lives. Many sensor nodes have been strategically positioned in rivers and oceans to closely monitor and analyze the underwater ecosystem. UWSNs face significant challenges due to energy limitations, unreliable communication channels, hole occurrence, and low packet delivery ratio. This paper introduces effective energy routing, hole detection and mitigation, and reliable delivery schemes to address these issues. In ERR-UWSN, a single-path routing strategy optimizes energy consumption by selecting the best-sending node through a unique weight function. However, the reliability of this approach is compromised in the harsh and unpredictable submarine environment. To overcome this limitation, co-ERR-UWSN combines cooperative routing with relay nodes between source–destination pairs. A carefully selected weight function ensures low energy consumption, reliability, and optimal node selection for data transmission. The simulation results show that ERR-UWSN is better than CEER, Co-EPRR, and FB-DBR in terms of residual energy, end-to-end delay, energy consumption, and total number of alive nodes. Also, Co-ERR-UWSN has a special advantage in the PDR criterion compared to other schemes. [ABSTRACT FROM AUTHOR]

Satellite synthetic aperture radar (SAR) provides ocean surface wind fields at 10 m above sea level. The objective is to investigate the capability of SAR satellite StriX observations for mapping offshore wind farm wakes. The focus is on the conditions under which an apparent wind speed‐up is generated, measured in 48% of the 67 images available. The results compare well to Sentinel‐1 observations, showing a 34% wind speed‐up rate during several years based on 1171 images. Three wind speed‐up cases have been studied in detail using the mesoscale Weather, Research, and Forecasting (WRF) model with two wind farm parameterizations. At 10 m above sea level, the SAR‐based observations and WRF model compare for most cases, though only when turbulent kinetic energy (TKE) is included in the wind farm parameterization. The TKE mixes higher momentum downward in a stable atmosphere, causing surface wind speed‐up near the surface. [ABSTRACT FROM AUTHOR]

Ocean data exhibits great heterogeneity from variances in measuring methods, formats, and quality, making it extremely complicated and diverse due to a variety of data kinds, sources, and study elements. A few examples of data sources are satellites, buoys, ships, self-driving cars, and distant systems. The processing of data is made more challenging by the significant regional and temporal variations in oceanic characteristics including temperature, salinity, and currents. This work presents an interactive tool for multivariate ocean parameter visualisation, specifically overlays, based on Python. In ocean data visualisation, overlays are extra visual layers or data points that are layered to improve comprehension over a basic map. Based on the available data and the visualisation goals, these overlays are chosen and blended. Users can customise overlays with this tool, which also supports formatting, 2D and 3D visualisation, and data preparation. In order to reduce artefacts, it uses kriging interpolation for 3D visualisation and a modified version of the ray casting algorithm for representing octree data. By integrating overlays like as bathymetry, currents, temperature, and marine life, users can produce visually appealing and comprehensive depictions of ocean data. This method provides a thorough grasp of intricate marine processes by making it easier to see patterns, trends, and abnormalities in the data. [ABSTRACT FROM AUTHOR]

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Marine biological nitrogen fixation (BNF) is crucial for introducing "new nitrogen" into the oceans. Over the past 30 years, numerous laboratory and on-board culture experiments have been conducted studying the effects of nutrients such as total dissolved nitrogen (TDN), total dissolved phosphorus (TDP), and dissolved iron (DFe) on marine diazotrophs such as Braarudosphaera bigelowii (B. bigelowii), Trichodesmium, Crocosphaera and noncyanobacterial diazotrophs (NCDs). Most studies concluded that elevated dissolved inorganic nitrogen levels inhibit nitrogen fixation in Trichodesmium, promote its growth, and have minimal effect on B. bigelowii. The impact on NCDs is unclear. Moreover, elevated dissolved inorganic phosphorus (DIP) levels can promote individual growth, population growth, and nitrogen fixation in most diazotrophs in P-limited marine environments. Dissolved organic phosphorus is a potential phosphorous source for diazotrophs in low-DIP environments. Elevated DFe can promote population growth and nitrogen fixation in diazotrophs in Fe-limited marine environments. At present, most diazotrophs have yet to achieve pure culture. Moreover, the effect of nutrients on diazotrophs is mainly limited to the study of a single nutrient, which cannot accurately reflect the actual Marine environment where diazotrophs live. As a result, our understanding of the effect of nutrients on diazotrophs is still insufficient. Future research focusing on the issues above and the development of innovative technologies and methodologies to investigate the impact of marine BNF is highly recommended, which will allow for a more precise assessment of the impact of marine BNF on global primary productivity while providing a scientific foundation for rational evaluation of ocean CO2 uptake and emissions. [ABSTRACT FROM AUTHOR]

The Argo array of profiling floats has considerably increased the observing capability of the three-dimensional global ocean and the knowledge of the ocean response to climate change. In particular, the Argo sampling has allowed observing relevant ocean indicators over the whole Mediterranean Sea especially during the last decade. In this study, the Mediterranean Argo network is comprehensively described from its spatio-temporal coverage to its capability to observe ocean monitoring indicators at sub-regional scale. For this purpose, the Argo array, as a non-interpolated product of profiles, is used to estimate the ocean heat and salt contents integrated within the upper, intermediate and deep layers over the period 2013-2022 in the different sub-regions of the basin. The same computational method is also applied to a model reanalysis product to estimate the impact of sampling of the sole Argo array. The sampling error is defined at sub-regional scale by comparing estimations from the whole model grid (full-sampled model) and from the Argo-like sampled model grid (sub-sampled model). Warming and salinification trends are well captured by the Argo array over the period of study, warming trends being the highest in the sub-regions of the western Mediterranean Sea from surface to depth and salinification trends being higher in the eastern sub-basin for the upper layer and in the western sub-basin for the deeper layers. This study also demonstrates the capability of the Argo array to capture local ocean structures and dynamics (e.g. anticyclonic and cyclonic gyres, intermediate and deep convection events and Atlantic Water inflows) and to account for their impact in the sub-regional variability of ocean heat and salt contents in the upper, intermediate and deep layers from seasonal to interannual scales. Considering these structures is fundamental for the understanding of the thermohaline circulation and changes observed in the Mediterranean Sea, and thus for future climate studies. [ABSTRACT FROM AUTHOR]

An observation operator in data assimilation was formalized based on the signatures extracted from the integral quantities contained within observed vertical profiles in the ocean. A four-dimensional variational global ocean data assimilation system, founded on this observation operator, was developed and utilized to conduct preliminary data assimilation experiments over a ten-year assimilation window, comparing the proposed method, namely profile-by-profile matching, with the traditional method, namely point-by-point matching. The proposed method not only demonstrated a point-by-point skill comparable to the traditional method but also provided superior analysis fields in terms of profile shapes on the temperature-salinity plane. This is an indication of a well-balanced analysis field, in contrast to the traditional method, which can produce extremely poor relative errors for certain metrics. Additionally, signatures were shown to successfully represent properties of the water column, such as steric height, and serve as an effective new diagnostic tool. The top-down, or macro--micro, viewpoint in this method is fundamental to the extent that it can offer an alternative view of how we comprehend ocean observations, holding significant implications for the advancement of data assimilation. [ABSTRACT FROM AUTHOR]

The Gulf Stream's (GS) impact on the marine boundary layer (MBL) is well established, yet the mechanisms and timescales through which it affects the upper‐troposphere and contributes to precipitation are debatable. Using a high‐resolution regional atmospheric model, we shed light on the impact of ocean intrinsic variability (OIV) along GS on midlatitude‐atmosphere. Taking advantage of a 24‐member ensemble of ocean model integrations, we devised a novel experimental setup where the same weather system feels different realizations of GS sea surface temperature (SST). We introduce the "Eddy Recharge‐Frontal Lift" (ERFL) mechanism, highlighting the joint importance of synoptic variability and boundary layer processes. ERFL mechanism proposes that OIV recharges/discharges MBL with moisture and heat, while convergence associated with passing atmospheric‐fronts uplifts these MBL‐trapped anomalies to upper‐troposphere and imprints on precipitation in surprisingly short periods (a month). The impact of OIV on precipitation depends on the background mean SST. Key Points: A novel modeling approach is used in the Gulf Stream region to isolate the influence of ocean intrinsic variability (OIV) on the atmosphereThe tropospheric response to OIV occurs through a collaboration between marine boundary layer (MBL) processes and atmospheric frontsOIV modulates moisture and heat in the MBL, whilst atmospheric fronts uplift these MBL‐trapped anomalies into the upper troposphere [ABSTRACT FROM AUTHOR]

The Early Paleozoic paleolatitudinal position of the terranes in the northern Tibetan Plateau is the key to unraveling the evolution of the Proto‐Tethys Ocean. We present the first Late Cambrian paleomagnetic results from the Oulongbuluke terrane (OT), in the northern Tibetan Plateau. The mean paleomagnetic direction for 16 sites is Ds = 196.2°, Is = −36.9° with κs = 31.5, α95 = 6.7°, corresponding to a paleopole at 68.2°S/51.9°E with dp/dm = 4.6°/7.8°. Rock magnetic and petrologic analyses demonstrate the primary origin of the magnetic mineralogy. This paleomagnetic result defines the Late Cambrian paleolatitude of the OT as 20.6 ± 4.6°S (reference point: 37.2°N/96.6°E). Combined paleomagnetic and geological evidence suggests that the terranes in the northern Tibetan Plateau were located to the northwest of the Indian plate of Gondwana during the Late Cambrian. Plain Language Summary: The Proto‐Tethys Ocean underwent a complex process of collision and amalgamation of the terranes in the northern Tibetan Plateau during the Early Paleozoic. Unraveling the Early Paleozoic paleogeography of these terranes is important for understanding the evolution of the Proto‐Tethys Ocean and is critical for reconstructing the formation of East Asia. However, quantitative constraints on the Early Paleozoic paleogeographic position of the terranes in the northern Tibetan Plateau are limited. Paleomagnetism is the only effective approach for directly constraining the paleolatitude of terranes. We conducted a paleomagnetic study of the Late Cambrian strata in the Oulongbuluke terrane (OT), northern Tibetan Plateau. The results define the paleolatitude of 20.6 ± 4.6 °S for the OT during the Late Cambrian. Based on paleomagnetic data and geological evidence, we also present a tentative paleogeographic reconstruction of the terranes in the northern Tibetan Plateau and the Proto‐Tethys Ocean in a global setting during the Late Cambrian. Key Points: We report the first Late Cambrian paleomagnetic results for the Oulongbuluke terrane (OT)The OT was located at ∼20.6°S during the Late CambrianThe terranes in the northern Tibetan Plateau may have been located northwest of the Indian plate during the Late Cambrian [ABSTRACT FROM AUTHOR]

An ocean memory framework is proposed to reveal the atmosphere's influence on ocean temperatures. Anomalous atmospheric forcing alters the ocean state through two mechanisms: short‐term, local effects involving air− ${-}$sea heat fluxes and Ekman circulation, and long‐term, far‐field effects involving changes from overturning and gyre circulations. The framework employs the Green function's method to incorporate both effects, enabling the quantification of ocean memory and the contribution of atmospheric forcing to ocean thermal variability. The framework is employed to examine the North Atlantic Oscillation's (NAO) influence on the North Atlantic Ocean variability, including the Atlantic Multidecadal Variability, with its memory estimated to be 10–20 $10\mbox{--}20$ years. The NAO and variability in the North Atlantic jet speed explain up to 30% of ocean decadal variability, primarily driven by temporal changes in ocean heat transport. Therefore, decadal fluctuations in ocean temperatures cannot be accurately modeled solely as a passive response to stochastic atmospheric forcing. Plain Language Summary: The atmosphere and ocean are intricately linked, with the ever‐changing atmosphere driving fluctuations in ocean temperatures. However, the atmosphere changes much faster than the ocean due to their different timescales and the ocean's ability to store excess heat for many years commonly referred to as ocean memory. As a consequence, isolating and understanding how short‐term atmospheric variations influence long‐term fluctuations in ocean temperatures, particularly on decadal timescales, can be difficult. To address this challenge, we introduce an ocean memory framework that allows us to analyze and quantify the atmosphere's contribution to ocean variability. We apply this framework to study how the North Atlantic Oscillation, a major atmospheric pattern in the northern hemisphere, influences decadal fluctuations in the subpolar North Atlantic Ocean temperatures. We estimate the ocean memory timescale in the subpolar North Atlantic to be about 10–20 $10\mbox{--}20$ years, which is how long temperature anomalies persist, while being redistributed, in the ocean before dissipating. Key Points: New ocean memory framework accounts for local response due to air‐sea fluxes and far‐field response due to ocean circulationThe framework is employed to quantify subpolar North Atlantic Ocean thermal variability due to the North Atlantic Oscillation (NAO)The framework captures the sign reversal in the correlation between the NAO and ocean temperatures across seasonal to decadal timescales [ABSTRACT FROM AUTHOR]

Accurately identifying clouds in satellite images is an important stage in processing such images for scientific use. Cloudy image pixels are labelled using a pixel mask, to allow them to be filtered out and ignored. The accuracy at which ‘cloud masking’ can be performed needs to be determined and this is often done by expert manual classification. Given the public enthusiasm for weather, we tested whether this classification could be performed reliably by ‘citizen scientists’. We found that the public could identify cloud with a 94% accuracy over ocean. Our analysis pointed to future improvements of the CloudCatcher project. [ABSTRACT FROM AUTHOR]

Ocean Vuong’s epistolary novel On Earth We’re Briefly Gorgeous is distinguished by its highly sensory, descriptive, and fragmented linguistic style, coupled with an anachronic, multi-line narrative strategy. These stylistic elements exemplify salient modernist aesthetics, particularly resonating with the tenets of the Imagist movement. Through the presentation of fleeting images and juxtaposed scenes across temporal and spatial boundaries, Vuong’s fiction delineates the narrator’s transient, synesthetic recollections which merge into a dynamic flow of conscious duration, constituting a notable queer racial formalist work. Moreover, Vuong’s richly sensory and affective portrayal facilitates an embodied engagement with external spaces, unraveling the complex layers of the protagonist’s Asian American queer identity. By integrating a corporeal perspective into the aesthetic process of receiving and composing, Vuong reconfigures the traditionally passive bottom role toward a more dynamic and inclusive queer performance, thus challenging the entrenched heteronormative constructions that comply with Western imperialist and masculinist discourses. Beyond empowering the “abject” bottom, Vuong’s novel also posits a shared vulnerability inherent in queer bodies, envisioning a side path for the minoritarian groups. [ABSTRACT FROM AUTHOR]

Upper-ocean fronts are an important component of the global climate system, regulating both the oceanic energy cycle and material transports. In the common paradigm, upper-ocean fronts are generated by frontogenesis at the mesoscale (20–300 km), driven predominantly by confluent horizontal flows initiated by a background straining field. However, the mechanisms by which this frontogenesis extends down to and influences the submesoscale (0.2–20 km), which dominates vertical transports in the ocean, are still understudied. Here, we provide direct observational evidence that submesoscale frontogenesis, defined as the rate at which submesoscale buoyancy gradients intensify, is closely linked to convergent flows. Analysis of year-long measurements by a mooring array in the North Atlantic indicates that both the upper-ocean frontogenetic rate and the horizontal convergence exhibit strong seasonality and scale dependence, with larger magnitudes in winter and at smaller horizontal scales (down to at least 2 km). The frontogenetic rate is found to correlate more strongly with horizontal convergence as the scale decreases, suggesting that convergent flows are the main driver of submesoscale frontogenesis. Crucially, a rapid forward cascade of kinetic energy and enhanced vertical velocities preferentially occur during periods of submesoscale frontogenesis. Our findings highlight a mechanism underpinning the key role of submesoscale fronts in the oceanic kinetic energy cascade and as a focus of vertical transports, and call for a parameterization of such effects in climate-scale ocean models. The authors present observational evidence revealing that submesoscale frontogenesis is determined by convergent flows and can lead to a forward cascade of kinetic energy and enhanced vertical velocities. [ABSTRACT FROM AUTHOR]

Small single-stranded DNA phages of the Microviridae family are diverse and prevalent in oceans. Our understanding of Microviridae phages that infect the ecologically important marine Roseobacter is currently limited, comprising few isolates. Here, we report six roseophages that infect Roseobacter RCA strains. Genomic and phylogenetic analyses revealed that they were new members of the previously identified subfamily Occultatumvirinae. Additionally, 232 marine uncultivated virus genomes (UViGs) affiliated to Occultatumvirinae were obtained from environmental genome datasets. Phylogenomic analysis revealed that marine Occultatumvirinae phages could be further grouped into 11 subgroups. Moreover, meta-omics based read-mapping analysis showed that Occultatumvirinae phages were globally distributed, with two low G + C subgroups showing the most prevalent distribution. Furthermore, one phage in subgroup 2 was found to be extremely ubiquitous. Overall, this study expands our understanding of the diversity and ecology of the Occultatumvirinae microviruses in the ocean and highlights their ecological impacts. Six roseophages that infect Roseobacter RCA are described as new Occultatumvirinae, to which further 232 marine uncultivated virus genomes obtained from environmental genome datasets could be assigned; these are globally distributed in 11 subgroups. [ABSTRACT FROM AUTHOR]

The magnificent catshark Proscyllium magnificum was described in 2004 based off five specimens collected in the Andaman Sea off Myanmar. It was originally allocated to the genus Proscyllium, but recent molecular analyses suggested it was more closely related to the harlequin catshark Ctenacis fehlmanni from the western Indian Ocean. This study incorporated meristics and external and internal morphology, together with molecular data to reclassify the magnificent catshark as Ctenacis magnificum and provides revised diagnoses for the genera Ctenacis and Proscyllium. Ctenacis consists of two allopatric Indian Ocean species, while Proscyllium is monotypic genus confined to the northwest Pacific. The revised Ctenacis can be distinguished from Proscyllium in having a broader and longer head (head length 21%–23% vs. 16%–18% of total length), distance between pectoral and pelvic bases shorter than head length (vs. greater than head length), more teeth (upper jaw with 80–86 vs. 46–62 tooth files), and a complex colour pattern of dark reddish‐brown blotches and saddles (vs. colour pattern of small black spots). A revised key to the genera of proscylliids and species of Ctenacis is provided. [ABSTRACT FROM AUTHOR]

Pantropical climate interactions across ocean basins operate on a wide range of timescales and can improve the accuracy of climate predictions. Here, we show in observations that Central Pacific (CP) El Niño-like sea surface temperature (SST) anomalies have coevolved with tropical South Atlantic SST anomalies on a quasi-decadal (~10-year) timescale over the past seven decades. During the austral autumn–winter season, decadal warm SSTs in the tropical CP effectively induce tropical SST cooling in the South Atlantic, mainly by strengthening the South Atlantic subtropical anticyclone via an extratropical atmospheric wave teleconnection in the southern hemisphere. Partially coupled pacemaker simulations corroborate the observational findings, indicating that tropical CP decadal SSTs play a primary pacing role, while Atlantic feedback is of secondary importance throughout the study period. Our results suggest that the tropical CP could be an important source of decadal predictability for tropical South Atlantic SST and the surrounding climate. [ABSTRACT FROM AUTHOR]

It has previously been shown that trends in sensible heat from climate models have had a substantial contribution to global precipitation changes. We illustrate that this is the case also in the most recent Coupled Model Intercomparison Project Phase 6 (CMIP6). However, we find that over the period since 1980 reanalyses do not support the reduction in sensible heat from the CMIP6 models and rather estimate a global increase in sensible heat which would contribute to a precipitation reduction. Satellite data over a period of two decades over global ocean generally show an opposite sign of the sensible heat trend to the CMIP6 models, similarly to the reanalyses. [ABSTRACT FROM AUTHOR]

Visible and microwave satellite measurements can provide the global whitecap fraction. The bubble clouds are three-dimensional structures, and a space-based lidar can provide complementary observations of the bubble depth. Here, we use lidar measurements of the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite to quantify global bubble depth from the depolarization. The relationship between CALIPSO bubble depth and wind speed from the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) and AMSR2 is similar to a recently derived relationship based on buoy measurements. The CALIPSO-based bubble depth data show global distributions and seasonal variations consistent with the high wind speed (> 7 m/s) but with some variance. We also found similarities between the CALIPSO bubble depth and the whitecap fraction from AMSR2 and WindSat. Our findings support the use of spaceborne lidar measurements for advancing the understanding of the 3D bubble properties, and the ocean physics at high wind speeds. [ABSTRACT FROM AUTHOR]

The Challenger Deep (CD) is the deepest known hadal trench in the world. Due to challenges in data sampling at extreme ocean depths, the Lower Circumpolar Deep Water (LCDW) transport and ocean circulation structure in the CD remain unclear. By analyzing data from an extra-deep current meter mooring array, here we find a three-layer circulation in the CD, transitioning downward from westward LCDW flow (about −1.866 ± 2.953 Sv, 1 Sv = 106 m3/s) to cyclonic circulation, and then to anticyclonic circulation. The westward flow reverses its direction during summer, giving evidence for bidirectional connectivity of deep-sea basins, while the cyclonic-anticyclonic circulation is relatively steady. The LCDW intrusion, local topography and turbulent mixing are crucial for modulating the three-layer circulation. Turbulent mixing plays a key role in driving the anticyclonic circulation. Our findings provide insights for understanding the hydrodynamic environment in the ocean's deepest areas. The study presents data from moorings in the Challenger Deep, the deepest known hadal trench in the world, showing a three-layer circulation structure, modulated by deep-water intrusion, topography and turbulent mixing. [ABSTRACT FROM AUTHOR]

Southern Hemisphere (SH) storminess has increased in the satellite era and recent work suggests comprehensive climate models significantly underestimate the trend. Here, we revisit this reanalysis-model trend discrepancy to better understand the mechanisms underlie it. A comprehensive like-for-like analysis shows reanalysis trends exhibit large uncertainty, and coupled climate model simulations exhibit weaker trends than most but not all reanalyses. However, simulations with prescribed sea surface temperature (SST) exhibit significantly greater storminess trends, particularly in the South Pacific, implying SST trend discrepancies in coupled simulations impact storminess trends. Using pacemaker simulations that correct Southern Ocean and tropical east Pacific SST trend discrepancies, we show that storminess trends in coupled simulations are underestimated because they do not capture the enhanced storminess resulting from Southern Ocean cooling and La-Nina-like teleconnection trends. Our findings emphasize large reanalysis uncertainty in SH circulation trends and the impact of regional SST trend discrepancies on circulation trends. [ABSTRACT FROM AUTHOR]

Arctic sea-ice extent has strongly decreased since the beginning of satellite observations in the late 1970s. While several drivers are known to be implicated, their respective contribution is not fully understood. Here, we apply the Liang-Kleeman information flow method to five different large ensembles from the Coupled Model Intercomparison Project Phase 6 (CMIP6) over the 1970-2060 period to investigate the extent to which fluctuations in winter sea-ice volume, air temperature and ocean heat transport drive changes in subsequent summer Arctic sea-ice extent. This allows us to go beyond classical correlation analyses. Results show that air temperature is the most important controlling factor of summer sea-ice extent at interannual time scale, and that winter sea-ice volume and Atlantic Ocean heat transport play a secondary role. If we replace air temperature by net shortwave and downward longwave radiations, we find that the sum of influences from both radiations is almost similar to the air temperature influence, with the longwave radiation being dominant in driving changes in summer sea-ice extent. Finally, we find that the influence of air temperature is more prominent during periods of large sea-ice reduction and that this temperature influence has overall increased since 1970. [ABSTRACT FROM AUTHOR]

This study presents the water column temperature data collected during several cruises on board the Italica, Araon and Laura Bassi research vessels, in the framework of the Climatic Long-term Interaction for the Mass balance in Antarctica (CLIMA), Southern Ocean Chokepoints Italian Contribution (SOChIC), and Marine Observatory of the Ross Sea (MORSea) projects, funded by the Italian National Antarctic Research Program (PNRA). Data were collected between New Zealand and the Ross Sea during the austral summers from 1994/1995 to 2023/2024. Across this chokepoint of the Antarctic Circumpolar Current, XBT Sippican T7 probes were launched with a regular 20 km sampling, providing temperature profiles with a vertical resolution of 65 cm and a maximum nominal depth of 760 m. All temperature profiles underwent a rigorous quality control, including a general malfunctioning verification, the removal of spikes, the consistency check of adjacent profiles, the comparison to regional oceanographic features and satellite altimetry observations, and a final visual check by operator. Data quality checks led us to discard about 12 % of acquired XBT measurements. This dataset contributes to the improvement of our understanding of Southern Ocean features, being highly valuable for studies focusing on climate variability, especially across the Antarctic Circumpolar Current and its fronts. Furthermore, we expect that the collected XBT data will serve as a useful tool for the calibration and validation of recent satellite observations and for the improvement of Southern Ocean oceanographic simulations. [ABSTRACT FROM AUTHOR]

Palisada corallopsis has a widely reported distribution in the western and eastern Atlantic and some areas of the Indo-Pacific Ocean, whereas P. furcata has a more restricted distribution, reported only from Brazil and Cuba. Palisada corallopsis and P. furcata were collected from their type localities, Havana, Cuba and Ceará, Brazil, respectively, and compared by morphological and molecular analyses using rbcL and COI-5P genes. The molecular results placed the sequences from the type locality of both species in the same clade, showing low genetic divergence, 0.95 % for rbcL and 1.6 % for COI-5P. Morphologically, the species share similar habits, with branchlets bi-to trifurcated, cortical cells that may be arranged as a palisade and connected by secondary pit-connections. Our detailed morphological observations, including examination of the type specimens, and molecular analyses demonstrate that P. corallopsis and P. furcata are conspecific, P. furcata being a later taxonomic synonym of P. corallopsis. [ABSTRACT FROM AUTHOR]

On 15 January 2022, a massive underwater eruption occurred at the Hunga Tonga‐Hunga Ha'apai Volcano. The plume reached the mesosphere, and the eruption excited a significant atmospheric Lamb wave, which forced the tsunami. The complicated tsunami waveforms due to ocean‐atmosphere coupling prevented inferring the force history of the excitation. To address this, we analyze ocean surface gravity waves (OSWs) from 15 to 40 mHz, which are decoupled from the Lamb wave due to their slower phase velocities. Modeling these OSWs, we infer that the excitation started at 4:00 UTC with an amplitude of 1010 $1{0}^{10}$ N and lasted for 5 hr, followed by a sub‐event at 8:40 UTC. The observations suggest an initial blowout of seawater above the summit and a subsequent outflow that excited a tsunami below 5 mHz. The 2 hr delayed OSW excitation from 6 to 15 mHz may indicate seawater inflow into the crater. Plain Language Summary: On 15 January 2022, the Hunga Tonga‐Hunga Ha'apai volcano experienced a massive underwater eruption. This eruption sent a plume into the atmosphere and produced a powerful atmospheric wave that caused an early arrival of the tsunami. The complex tsunami propagation coupled with the atmospheric wave prevents us from understanding the excitation processes. To address this, we focussed on ocean surface gravity waves (OSWs) in an oscillatory period from 25 to 67 s, also interpreted as short‐period tsunamis. These OSWs are less affected by these atmospheric waves because of the slow propagation speed. Because the OSWs are less influenced by ocean depth, they are easier to model. The observed OSWs show that the eruption started at 4:00 UTC with a vertical force of approximately 1010 $1{0}^{10}$ N and continued for about 5 hr. Another significant sub‐event occurred around 8:40 UTC. Furthermore, the OSWs in an oscillatory period from 67 to 167 s arrived about 2 hr after the short‐period OSWs. These observations suggest that the eruption blew seawater above the volcano's summit and a subsequent outflow that excited a tsunami. The 2 hr delay in low‐frequency OSW could indicate that seawater flowed into the crater. Key Points: Ocean surface gravity waves at 15–40 mHz were excited at 4:00 UTC when an underwater eruption occurred at Hunga Tonga‐Hunga Ha'apai VolcanoA significant sub‐event at about 8:40 UTC followed the main event, and the ocean surface gravity waves lasted for half a dayThe observations of ocean surface gravity waves suggest a blowout of seawater above the summit and the inflow of seawater into the crater [ABSTRACT FROM AUTHOR]

Unlike prior researches focusing on interannual or interdecadal changes of the Northwest Pacific subtropical high (NWPSH), this paper emphasizes the interdecadal changes in the relationship between May‐June and July‐August NWPSH. The correlation coefficients between them are 0.66 (passing the 99.9% confidence level) and 0.12 during 1979–2002 and 2003–2023. Therefore, the May‐June NWPSH has a strong connection with July‐August East Asian precipitation during 1979–2002, but not during 2003–2023. The interdecadal variations in the relationship of NWPSH are due to interdecadal changes of ENSO. During 1979–2002, the eastern‐type ENSO in prior winter, having longer durations, can influence May‐June and July‐August NWPSH and the North Indian Ocean. However, the central‐type ENSO in prior winter only persists it's influence until May‐June, and changes into a Pacific Dipole pattern in July‐August during 2003–2023. Despite the North Indian Ocean continually warms during 2003–2023, the tropical Pacific Dipole offsets its impacts on the NWPSH. Plain Language Summary: The Northwest Pacific Subtropical High (NWPSH) has always been valued by meteorologists due to its important role in the East Asian climate. This paper found that the relationship between the NWPSH in May‐June and July‐August has weakened significantly since 2002. The eastern‐type ENSO, characterized by longer durations, can influence the NWPSH and the North Indian Ocean in May‐June and July‐August before 2002. However, from 2003 to 2023, the influence of the central‐type ENSO only persists until May‐June, transitioning to a Pacific Dipole pattern in July‐August. Therefore, both May‐June and July‐August NWPSH are affected by the North Indian Ocean before 2002. However, the NWPSH in May‐June is affected by the North Indian Ocean and prior winter ENSO after 2002, while the July‐August NWPSH is impacted by the tropical Pacific Dipole. And the tropical Pacific Dipole also offsets the influence of the North Indian Ocean on the NWPSH. This leads to a weakening of the relationship between the NWPSH in May‐June and July‐August. Key Points: The relationship between the Northwest Pacific subtropical high (NWPSH) in May‐June and July‐August has significantly weakened after 2002The reason for weakening relationship of NWPSH is that the persistent eastern ENSO has become a short‐period central ENSO after 2002Central ENSO will become Pacific Dipole mode in summer, which will weaken the influence of North Indian Ocean on NWPSH [ABSTRACT FROM AUTHOR]

The Indonesian Throughflow (ITF) thermocline, as exclusive water source for the "warm water route" of the Atlantic Meridional Overturning Circulation (AMOC), provides waters that exit the Indian Ocean and join the AMOC upper limb via the Agulhas Leakage (AL). Hence, investigating long‐term variations in the ITF thermocline and its implications on the AL is important for understanding dynamics of the AMOC. Here, the thermohaline history of the ITF thermocline was reconstructed for the last ∼410 kyr based on δ18O and Mg/Ca of planktonic foraminifera from International Ocean Discovery Program Site U1483. By integrating the new and published records, we found that precession drives variation of the ITF thermocline through modulating the intensity of the Australian‐Indonesian winter monsoon, El Niño‐Southern Oscillation‐like states and formation of the North Pacific Tropical Water, in turn exerting a transoceanic influence on the amount of the AL and seawater temperature and salinity of the South Atlantic thermocline. Plain Language Summary: It is widely acknowledged that the Indonesian Throughflow (ITF), a key component of the global thermohaline circulation, plays an important role in the global climate and ocean circulation. However, in contrast to concentrating on the factors that shaped the ITF in the geological history, few studies considered the ITF as a factor to influence climate and ocean circulation, especially on long timescales. In this study, we utilized shell δ18O and Mg/Ca of a planktonic foraminiferal thermocline‐dwelling species from the Timor Sea, the main outflow passage of the ITF, to reconstruct the temperature and salinity changes of the ITF thermocline during the past ∼410 kyr. By integrating the new and published paleo‐oceanographic and ‐climatological records, we found that the ∼20‐kyr wobbles of the Earth's axis (precession) induced variations in the flow strength and seawater temperature and salinity of the ITF thermocline, and in turn regulated the amount of the Agulhas Leakage and seawater temperature and salinity of the South Atlantic thermocline. Our results underscore the essential role of the ITF in the connectivity among the oceans. Key Points: Precession drove variations in the ITF thermocline by modulating the intensity of the Australian‐Indonesian winter monsoon, ENSO‐like states and formation of the North Pacific Tropical WaterVariations in the ITF thermocline regulated the amount of AL and seawater temperature and salinity of South Atlantic thermocline [ABSTRACT FROM AUTHOR]

The three‐dimensional structure of the Tropical Cyclone's baroclinic wake is synthesized as an averaged baroclinic‐dominant response of the upper ocean. The resulting persisting sea surface depression can easily be monitored using the present‐day altimeter constellation. Following a semi‐empirical framework, these baroclinic wake signatures are linked to the inner core TC dynamic and the ocean stratification. To collect these fine‐scale parameters, spaceborne SAR instruments and Argo fleet are used, to precisely capture the maximum wind region and the irregularities of the ocean vertical structure. This combination of high‐resolution information is found paramount to fully capture the modulation of sea surface height anomalies, and its mean trend, especially for major hurricanes. Baroclinic signatures mostly range around 10–20 cm and peak at 40 cm. Deeper anomalies correspond to barotropic response, removed from the present analysis. Plain Language Summary: In the wakes of Tropical Cyclones (TCs), sea surface depressions of about 10 cm appear. These TC signatures are persistent enough to be easily monitored by the current fleet of altimeter instruments. A measured sea surface height anomaly integrates and reduces the air/sea interactions during the TC passage into a single observable metric. It mostly encodes the cyclonic wind forcing and the interior ocean state. A broad constellation of remote sensing and in‐situ instruments has been gathered to compile 200 cyclonic episodes, collecting a wide range of TC sizes, intensities, and translation speeds together with oceanic conditions. A synthetic relationship is found to robustly predict most observed sea surface height anomalies. Moreover, when high‐resolution information is available to estimate the ocean interior state and the TC radius of maximum winds. Such a diagnostic thus explains the dominant baroclinic ocean response to a TC passage, and, inversely, can be used to infer ocean stratification or forcing parameters in the absence of high‐resolution observations. Key Points: Residual sea surface height anomalies from the cold wakes of Tropical Cyclones are analyzed using a multi‐modal approach at global scaleA scaling law provides a robust interpretation of the baroclinic response to given ocean stratification and forcing conditionsHigh resolution measurements are found critical to correctly anticipate the SSHA amplitudes with localized pre‐storm ocean stratification [ABSTRACT FROM AUTHOR]

The convergence analysis for least-squares finite element methods led to various adaptive mesh-refinement strategies: Collective marking algorithms driven by the built-in a posteriori error estimator or an alternative explicit residual-based error estimator as well as a separate marking strategy based on the alternative error estimator and an optimal data approximation algorithm. This paper reviews and discusses available convergence results. In addition, all three strategies are investigated empirically for a set of benchmarks examples of second-order elliptic partial differential equations in two spatial dimensions. Particular interest is on the choice of the marking and refinement parameters and the approximation of the given data. The numerical experiments are reproducible using the author's software package octAFEM available on the platform Code Ocean. [ABSTRACT FROM AUTHOR]

In this paper, we propose a phase-based pseudorange estimation and source localization algorithm to improve the localization performances of ultrashort baseline (USBL) systems. The conventional USBL system estimates pseudorange through cross-correlation of received chirps. However, due to the limited sampling rate, precise pseudorange cannot be estimated, resulting in low localization performance. The proposed method calculates the number of wavelengths between the transducer and receiver and detects the initial phase to estimate the pseudorange more accurately than the conventional method. It also improves localization performance by estimating and compensating for phase variations by underwater channels. The source localization performances of the proposed method and the conventional methods were compared and analyzed through computer simulations and ocean experiments, and the proposed method had better localization performances than the conventional methods. [ABSTRACT FROM AUTHOR]

Understanding the impacts of the Indonesian Throughflow (ITF) on the eastward propagation of the Madden-Julian Oscillation (MJO) is crucial for accurately simulating the MJO and achieving high-skill sub-seasonal predictions. Our analyses demonstrate a significant enhancement of MJO eastward propagation due to the strong ITF. Blocking the ITF decreases the eastward sea surface temperature (SST) gradient over the tropical Indian Ocean, hindering MJO propagation across the Maritime Continent (MC). Removing the MJO circulation-induced intraseasonal variability of the ITF transport also weakens the eastward propagation of the MJO, as the MJO easterly winds enhance the ITF transport and warm the eastern tropical Indian Ocean. These experiments reveal that mean and intraseasonal variability of the ITF transport contribute to 73% and 42% of the eastward propagation of the MJO over the MC, respectively. The findings presented in this study highlight the significant role of the ITF in shaping the propagation of the MJO. [ABSTRACT FROM AUTHOR]

Skin photoaging, caused by prolonged exposure to ultraviolet (UV) radiation, manifests as intricate biological transformations, encompassing oxidative damage and structural alterations. Despite a growing need for effective interventions, the existing therapeutic repertoire for treating skin photoaging remains constrained. Recent investigations have shifted focus towards the application of hydrogels as a novel avenue for addressing this concern. Various active substances can be combined with hydrogels for transdermal delivery, including compounds from the ocean, plants, cell active substances, which can promote skin UV damage repair mainly through antioxidant, antiinflammatory and promote collagen production. This review seeks to offer a thorough summary of recent progress in employing hydrogels for addressing skin photoaging. Topics covered include the mechanism of skin photoaging, and emerging trends in hydrogel-based therapies for skin rejuvenation. The discussion also explores challenges and outlines potential future directions in leveraging hydrogels as therapeutic agents to address skin photoaging. [ABSTRACT FROM AUTHOR]

Polar sea surface height observation by radar altimeters requires missions with high-latitude orbit and specific processing to observe the sea-ice-covered region within fractures in the ice. Here, we combine sea surface height estimates from different radar satellites over the ice-free and ice-covered polar oceans to create cross-calibrated along-tracks and gridded products over the Arctic Ocean (2011-2021) and the Southern Ocean (2013-2021). The sea surface height from our regional polar products is in great agreement with tide gauges and bottom pressure recorders at monthly timescales in seasonally to year-round icecovered regions. Thanks to the use of several missions and the mapping strategy, our multi-mission products have a greater resolution than monomission products. Part of the sea level variability of the Arctic Ocean product is related to the Arctic Oscillation atmospheric circulation. At long term, the Arctic altimetry sea level is coherent with in-situ steric height evolution in the Beaufort gyre, and negative sea level trends over the 10-year period are observed in the East Siberian slope region, which may be related to the local freshwater decrease observed by other studies. Our regional polar sea level products are limited by current understanding of the sea-ice lead measurements, and homogenization of these polar products with global sea level products needs to be tackled. [ABSTRACT FROM AUTHOR]

The East African March–April–May (MAM, "long rains") precipitation decline in recent decades remains a puzzle marked by various proposed large‐scale drivers. Here, the interannual variability of the long rains and their recent drying trend are examined using global model simulations and observations. Comparison of a control simulation and re‐initialized simulations in which land‐surface feedback is suppressed shows that much of the long rains deficit experienced between 1980 and 2014 is synchronized with the warming of the Northwestern Eurasian landmass. In agreement with the modeling results, multiple observational data sets reveal a strong negative correlation between MAM mean East African rainfall amount and the surface temperature over Northwestern Eurasia. Idealized simulations further indicate that warming in Northwestern Eurasia weakens the regional Hadley Cell and diverts the monsoonal transport of moisture away from Eastern Africa toward Europe and southern Africa, highlighting the role of remote land surface warming on the observed precipitation decline. Plain Language Summary: In this article the inter‐annual variability and the observed long‐term decline of Boreal spring rainfall over Eastern Africa are examined. Previous research on the causes of these droughts focused on sea surface temperature variability over tropical oceans. In this work through extensive analysis of observations and global modeling we show that land‐surface feedbacks over Northwestern Eurasia are the primary culprit. More broadly the work highlights the importance of teleconnections between regional climates through remote impacts of land surface feedbacks. Key Points: We demonstrate a co‐variability of East African March–April–May rainfall (long rains) and surface temperature over Northwestern EurasiaAnalysis of model simulations show warming Northwestern Eurasia weakens the local Hadley cell and introduces subsidence over East AfricaThe observed decline in East African March–April–May rainfall observed during 1980–2014 can be explained by this warming [ABSTRACT FROM AUTHOR]

Atmospheric rivers (ARs) are key agents in distributing extratropical precipitation and transporting moisture poleward. Climate models forced by historical anthropogenic forcing suggest an increase in AR activity in the extratropics over the past four decades. However, reanalyses indicate a ~6° to 10° poleward shift of ARs during boreal winter in both hemispheres, featuring a rise along 50°N and 50°S and a decrease along 30°N and 30°S. Our analysis demonstrates that low-frequency sea surface temperature variability in the tropical eastern Pacific exhibits a cooling tendency since 2000 that plays a key role in driving this global AR shift, mostly over extratropical oceans, through a tropical-driven eddy-mean flow feedback. This mechanism also operates on interannual timescales, controlled by the El Niño-Southern Oscillation, and is less pronounced over the Southern Ocean due to weaker eddy activity during austral summer. These highlight the sensitivity of ARs to large-scale circulation changes driven by both internal variability and external forcing in current and upcoming decades. [ABSTRACT FROM AUTHOR]

Starting in 1969, small groups of West Papuans have occasionally crossed the Torres Strait to Australia and sought its protection. In public discourse, these arrivals have figured as part of a narrative about Australia’s relationship with Indonesia. By contrast, in the public discourse about border control, which focuses on attempted travel across the Indian Ocean and distinct ‘waves’, they have been treated as a footnote, at most. In this article, we closely examine the Australian government’s response to West Papuan ‘boat people’ over time to demonstrate that, unlike in public discourse, border control considerations have loomed large in the government’s response. We argue that, in order to understand Australia’s approach to border control, we should see West Papuan asylum seekers in the context of border control policy and not only as a problem in Australia’s relationship with Indonesia. [ABSTRACT FROM AUTHOR]

AbstractThis paper shows how and why it is ‘im-possible’—i.e. simultaneously possible and impossible—for humans to travel and stay underwater by narrating the story of how Jules’ Undersea Lodge was designed and how its guests can remain there for relatively long periods of time. Drawing from interviews with its designer, Ian Koblick, reflexive ethnographic material collected at Key Largo’s (Florida) Jules’ Undersea Lodge in the early spring of 2024, and an interview with Joseph Dituri—who in 2023 set a world record for the longest time spent in an underwater habitat – we conceptualize im-possibility as a dialectical tension between possibility and impossibility. [ABSTRACT FROM AUTHOR]

Atlantic bluefin tuna (ABFT; Thunnus thynnus) is a highly migratory species. To investigate the migrations and vertical behaviours of ABFT migrating to Nordic waters, we deployed pop-up satellite archival transmitting tags on 25 ABFT off Norway (curved fork length: 228–292 cm). We obtained 16 full-year migrations, which differed between individuals, and physically recovered 13 tags, which provided 4699 days of archival depth and temperature data. ABFT occupied waters from the Arctic Circle to as far south as Cabo Verde, Africa, and occupied depths down to 1190 m and temperatures from 0.5 to 27.8°C. During their annual migrations, ABFT spent, on average, 68 days in Norwegian waters, 65 days in the Newfoundland Basin, 35 days around the Canary Islands and 33 days in the West European Basin. Most ABFT entered the Mediterranean Sea with a mean entry date of 13 May and visited known spawning grounds, staying, on average, 44 days. All ABFT with full-year deployments returned to Norwegian waters. ABFT displayed high site-fidelity and dynamic vertical diving behaviours that varied between hotspots and seasons. These spatiotemporal data provide important ecological knowledge for sustainable management and the conservation of the recently recovered eastern ABFT stock. [ABSTRACT FROM AUTHOR]

A new dedicated coastal sea level dataset called the International Altimetry Service 2024 (IAS2024, https://doi.org/10.5281/zenodo.13208305 , Peng et al., 2024c) has been presented to monitor sea level changes along the world's coastlines. One of the reasons for generating this dataset is the quality of coastal altimeter data has been greatly improved with advanced coastal reprocessing strategies. In this study, the Seamless Combination of Multiple Retrackers (SCMR) strategy is adopted to obtain the reprocessed Jason data for January 2002 and April 2022. The evaluation results show that the data availability of the IAS2024 dataset over global coastal oceans is much higher than that of the European Space Agency Climate Change Initiative version 2.3 (ESA CCI v2.3) dataset. The closure of trend differences (0.16 ± 3.98 mm yr−1) between IAS2024 and Permanent Service for Mean Sea Level (PSMSL) tide gauge data is observed at the global scale, which further demonstrates the good performance of the IAS2024 dataset in monitoring the coastal sea level changes. The altimeter-based virtual stations have been built with the IAS2024 dataset over 0−10 km, 5−15 km and 10−20 km coastal strips, which will contribute to the analysis of coastal sea levels for the ocean community and the risk management for the policy makers. Our study also points out that no obvious variations exist in linear sea level trends from offshore to the coast in most coastal zones. In addition, the vertical land motion (VLM) estimates from the combination of coastal altimeter data with tide gauge records agree well with the University of La Rochelle 7a (ULR7a) Global Navigation Satellite System (GNSS) solution (0.09 ± 2.22 mm yr−1), suggesting that altimeter-derived VLM estimates can be an independent data source to validate the GNSS solutions. [ABSTRACT FROM AUTHOR]