A modern climate model is used to test the hypothesis that changes observed during El Niños are, in part, forced by changes in the temperature of the North Equatorial Counter Current. This is a warm current that flows eastwards across the Pacific, a few degrees north of the Equator, close to the Inter-Tropical Convection Zone, a major region of deep atmospheric convection. The tests generate a significant El Niño type response in the ocean, giving confidence that the hypothesis is correct.

We identify the Mexican Coastal Current interaction with coastline using sea level anomaly and derived geostrophic velocities, finding that an average width of 95 km and an average speed of 0.3 m/s width seasonal variability. Numerical modeling proves that interaction of coastal current with the coastline generates ocean eddies in some places that form a wide concavity. These eddies are formed while the current is present getting intense and detaching from the coast until the current weakens.

This study investigated the effects of salt fingering on particle and solute distribution in the Tyrrhenian Sea. Density interfaces associated with thermohaline staircases slow the settling of suspended particles and promote aggregation. This affects particle size distribution and creates nutrient and oxygen gradients, affecting microbial activity and nutrient cycling. The research highlights the potential role of salt fingers in deep ocean biogeochemical processes.

This study presents a new method to improve the accuracy of sea level height from the Ieodo Ocean Research Station in the East China Sea. The method helps identify data errors, such as repeated or unusual values, and flags extreme weather events. The analysis found that sea level rise are mostly due to ocean mass changes, with local ground subsidence also playing a role. This high-quality data supports research on short-term and long-term events, helping coastal monitoring and planning efforts.

The study presents an operational service that forecasts flood impacts during extreme conditions at three beaches in Barcelona, Spain. The architecture is designed for efficient use on standard desktop computers, using data from the Copernicus Marine Environment Monitoring Service, task automation tools, Python scripts, and the XBeach model to deliver timely results. Extensive validation, including field campaigns and video analysis, ensures accuracy and reliability.

The ocean buffers human-caused climate change by taking up excess heat from the atmosphere. In this study, we use an ensemble of global climate models to study the physical processes which set the efficiency at which this heat is stored in the ocean. We reconcile previous attempts at explaining controls on this efficiency and find that Southern Ocean stratification is a key model property due to its influence on the local overturning circulation and its connection to the subpolar North Atlantic.

Current observations at two moorings in the northern South China Sea reveal that mesoscale eddies can transfer energy with near-inertial oscillations (NIOs). Numerical experiments are conducted to investigate important parameters affecting energy transfer between mesoscale eddies and NIOs, which demonstrate that the energy transferred by mesoscale eddies is larger with stronger winds and higher strength of the mesoscale eddy. Anticyclonic eddies can transfer more energy than cyclonic eddies.

Coastal zones are crucial ecological areas, yet our understanding of groundwater-ocean interactions remains limited. Ocean and groundwater models typically operate independently, with ocean models ignoring submarine groundwater discharge and groundwater models viewing the ocean as a static boundary. This separation impedes accurate simulations. By integrating these models, we can capture real-time water flow and salt movement while considering factors such as tides.

The temperature and salinity trends at various depths in the Baltic basins from 1990 to 2020 were analyzed from a reasonable reanalysis data set. Overall, the Baltic Sea showed a clear warming trend in recent decades, the northern Baltic Sea has a slight desalination trend, and the southern Baltic Sea has a salinity increase trend. The temperature and salinity trends in the southern Baltic Sea are greater than those in the northern Baltic Sea.

A combined procedure of benzalkonium chloride (BAC) addition and filtration was investigated to preserve water samples for radiocarbon analysis of dissolved inorganic carbon (DIC). The results indicated that DIC changes can be effectively suppressed during sample storage for up to 41 weeks. This procedure offers a practical, environmentally friendly alternative to conventional mercury-disinfected methods, effectively water sample preservation samples in aquatic environments.

Quantifying the carbon budget in the ocean is logistically difficult and costly. Specifically, measuring the movement of CO₂ across the air–sea interface requires expensive analyzers. To combat this, our group has developed a low-cost ΔpCO₂ system, called The Sensor for the Exchange of Atmospheric CO₂ with Water (SEACOW). We demonstrate the SEACOW’s ability to capture pCO₂ cycling, provide recommendations for SEACOW field deployments, and provide technical specifications for the SEACOW.

This paper describes results from an underwater robot (glider) deployment in the energetic waters of Te-Moana-o-Raukawa. The glider data showed how energy is transferred from winds and tides to turbulent processes. We found that boundary layers of strong turbulence typically can impact the water from surface to seafloor, except when pockets of fresher or warmer water move into the region. Numerical simulations showed that turbulent energy transport was crucial for boundary layers to interact.

This study explores how wind and wave dynamics affect the movement of riverine sediment to the ocean. Using advanced modeling, we found that most riverine sediment stays near the estuary in wet summer, with strong winter winds resuspending it for transport. Our findings highlight the significant impact of seasonal changes on sediment movement, which is crucial for understanding coastal ecosystems and managing sediment-related challenges.

This study examines how multiple processes in the Northern Red Sea form the Red Sea Outflow Water and affect biogeochemical fluxes. Using glider data, wind and air-sea flux reanalysis, and satellite observations, it highlights seasonal evolution. Eddy-driven upwelling exposes cool water to heat loss and evaporation, fueling primary productivity. Circulation patterns block inflows, extend cooling, and subduct water into the ocean interior, influencing regional dynamics.

The West African coastal region sustains highly productive fisheries and marine ecosystems influenced by sea surface temperature. We use oceanic models to show that the freshwater input from land to ocean strengthens a surface northward (southward) coastal current north (south) of the Congo river mouth, promoting a transfer of cooler (warmer) waters to north (south) of the Congo discharge location. We highlight the significant impact of river discharge on ocean temperatures and circulation.

In the Western Alboran Gyre, waters from the Atlantic and Mediterranean meet, creating density differences that cause some water to sink, affecting ocean ventilation and nutrient cycles. We collected data showing patches of water with higher oxygen and chlorophyll levels moving towards the gyre's center, with active mixing at their edges. This mixing diluted the patches, and other factors like water density and light penetration likely played a role in these dynamics.

This study enhances the prediction of sea surface currents using HF radar data, addressing a gap in understanding how seasonal and monthly data segmentation affects accuracy. By applying RF Regression, we developed three prediction schemes that demonstrated larger datasets yield higher correlation coefficients, while tailored models reduce prediction errors. Key findings reveal that selecting the appropriate dataset and integrating moving averages significantly improves predictive performance.

This study measured pCO₂ in Nanwan Bay, a coral reef ecosystem in Southern Taiwan, to identify the factors driving its variability. The results indicate that Nanwan Bay is a highly dynamic ecosystem, with notable spatial and seasonal changes in carbon exchange. Surface water carbon parameters in this biodiverse subtropical marine environment are influenced not only by seasonal temperature fluctuations but also by vertical mixing, intermittent upwelling, and biological processes.

Eddies are rotating ocean currents up to hundreds of kilometers in diameter and phytoplankton are affected by their motions. We used satellites and simulations of currents to examine the effect of eddy trapping strength on phytoplankton concentration. Coherent eddies localize phytoplankton, whereas dispersive ones have lower concentrations because they mix with surrounding waters. However, we highlight the complex regional and seasonal variability of biological-physical interactions in eddies.

In this study, direct measurements from three moorings are utilized to reveal the intraseasonal variability of the North Pacific Intermediate Water in different regions for 60–80 days. It was found that the intraseasonal variation of NPIW is mainly caused by mesoscale eddies. Understanding these dynamics is critical for assessing the NPIW's response to climate change and its implications for the global carbon cycle and marine ecosystems.

This study explores ocean currents around Curaçao and how land-derived substances like pollutants and nutrients travel in the water. Most substances move northwest, following the main current, but at times, ocean eddies spread them in other directions. This movement may link polluted areas to pristine coral reefs, impacting marine ecosystems. Understanding these patterns helps inform conservation and pollution management around Curaçao.

This study explores the utilization of dynamic topography (that refers to the geoid) to quantify some key components of the Baltic water budget: the dynamic volume of the Baltic Sea, river runoff, and the Baltic inflow/outflow are examined. The method and results show great potential for quantification, validation, and a better understanding of the dynamics of the Baltic Sea, especially with a changing climate.

Particle tracking models allow us to explore pathways of floating marine litter, source-to-sink, between countries. This study showed the influence of seasonality for dispersal in Bay of Bengal and how ocean current forcing impacts model performance. Most litter beached on the country of origin, but there was a greater spread shown between countries during the post-monsoon period (Oct–Jan). Results will inform future model developments as well as management of marine litter in the region.

Zooplankton diel vertical migration (DVM) shapes ocean biogeochemical cycles. We present a new DVM model that reproduces migration depths observed in the North Atlantic Ocean. We show that chlorophyll shading contributes to reducing zooplankton migration depth and mainly controls its spatial and temporal variability. Thus, high chlorophyll concentrations may limit carbon sequestration caused by zooplankton migration despite the general abundance of zooplankton migration in these environments.

A new method improves the accuracy of climate models by adjusting wave spectra simulations in the Mediterranean Sea. It corrects biases and accounts for changes in wave patterns due to climate change, such as shifts in direction and frequency. This technique was applied to multiple climate models, assessing future wave conditions for mid and end-of-century scenarios. The results underline the importance of precise corrections to better predict how waves may evolve as the climate changes.

Our research evaluated the precision of mapping the ocean's surface with combined data from a couple of satellites, focusing on dynamic aspects revealed by sea level changes. Results show that 2DVAR, a new mapping product, aligns more closely and with less error with the most advanced satellite detailed observations than a widely used mapping product called AVISO. The results suggest that 2DVAR better detects minor ocean movements, making it more valuable and reliable for ocean dynamics study.

The present study explores the capabilities of four satellite missions in assessing the true resolution of the sea surface. A new weighted averaging method is introduced in the analysis of global sea surface height slope maps. The results show that SWOT significantly improves the accuracy and mesoscale resolution capability. Using the correlation method of mutual power spectra, we define a new parameter, ocean dynamics scale variability, and apply this parameter to the global ocean.

Mesoscale eddies are rotating structures in the ocean. This study investigates the surface and subsurface characteristics of mesoscale eddies in the vicinity of Perth submarine canyon off the southwest coast of Western Australia using Ocean Gliders. Eight Seaglider missions that intersected eddies revealed nine distinct vertical structures, comprising four cyclonic and five anti-cyclonic eddies. There was upwelling in cyclonic eddies and downwelling in anti-cyclonic eddies. 

The South China Sea is the largest semi-enclosed marginal sea in the western Pacific, features with unique layered circulation with rotating currents in its upper, middle, and deep layers. This study uses simulations to explore how stronger currents in the upper layer influence circulation across the entire basin. The vorticity analysis show that the enhanced upper currents increase the strength of middle and deep currents, driven by changes in bottom pressure and cross-slope movements.

Water isotopes in the ocean trace the freshwater exchanges between the ocean, the atmosphere and the cryosphere, and are used to investigate processes of the hydrological cycle. We illustrate offsets in seawater isotopic composition between different data sets that are larger than the expected variability that one often wants to explore. This highlights the need to share seawater isotopic composition samples dedicated to specific intercomparison of data produced in the different laboratories.

Concave coast act as funnel, concentrating storm waters and leading to higher storm surges (SS), while convex coast redistribute waters, reducing surges. Study uses the ADCIRC model to simulate peak surges (PS) for different cyclone tracks, showing how coastline geometry, landfall location, and cyclone angle influence PS. Cyclones passing near concave coasts without landfall can still cause high SS, highlighting vulnerability in these regions. This insight aids in assessing coastal flood risks.

We investigate the structural changes the Antarctic Slope Front in the southern Weddell Sea experiences in a warming climate by conducting two ocean simulations driven by atmospheric data of different horizontal resolution. Cross-slope currents associated with a regime shift from a cold to a warm Filchner Trough on the continental shelf temporarily disturb the structure of the slope front and reduce its depth, but the primary reason for a regime shift is the cross-slope density gradient.

While preparing a new set of sea level scenarios for the Netherlands, we found out that many climate models overestimate the changes in ocean circulation over the last 30 years. To quantify this effect, we defined three methods that rely on diverse and independent observations: tide gauges, satellite altimetry, temperature and salinity in the ocean, land ice melt, etc. Based on these observations, we select the best climate models to produce better sea level projections.

The Arabian Sea mini warm pool matures in the southeastern Arabian Sea in May and the influence of the ocean and atmosphere on its formation is debated for the past two decades. Using a coupled numerical model, our study concludes that both the oceanic and atmospheric conditions are necessary for its genesis. For instance, in a robust Mini Warm Pool year, the pre-April ocean condition primarily influences its formation, which is further favored by the presence of a 'wind shadow zone.'

The extent of mankind’s influence on Earth’s climate warrants ocean-studies. A supposed major heat-transporter is the Atlantic Meridional Overturning Circulation (AMOC). As AMOC is a complex nonlinear dynamical system, mathematical models may predict its potential collapse using single parameters like surface temperature. However, physical processes such as (sub-)mesoscale eddy transport and turbulent mixing by internal wave breaking will alter the estimators, so that the AMOC may not collapse.