Sea level in the South Atlantic Ocean has only been measured at a small number of tide‐gauge locations, which causes considerable uncertainty in 20th‐century sea‐level trend estimates in this basin. To obtain a better‐constrained sea‐level trend in the South Atlantic Ocean, this paper aims to answer two questions. The first question is: can we combine new observations, vertical land motion estimates

A series of 40‐year significant wave height (SWH) data were extracted from the ERA‐Interim data set of the European Centre for Medium‐Range Weather Forecasts (ECMWF) for the Beibu Gulf and its adjacent waters in the South China Sea from 1979 to 2018. After that, data were first aggregated to annual and monthly average data. Through the analysis, the annual SWH had grown since 1984, reached a significant

The sensitivity of the overturning circulation in the Baltic Sea is analyzed with respect to long‐term changes in atmospheric and hydrological conditions by using two state‐of‐the‐art ocean circulation models: RCO (Rossby Centre Ocean model) with a reference simulation and various sensitivity experiments as well as MOM (Modular Ocean Model). Historical reconstructions since 1850 lasting for >150 years

Systematic surveys to examine seasonal variation, degradation, and bioavailability of dissolved organic matter (DOM) in the Changjiang Estuary and the adjacent East China Sea (ECS) were conducted in July 2016 and February 2017. Concentrations of dissolved organic carbon (DOC) and total hydrolyzable amino acids (THAA) were higher in July than in February. THAA and chlorophyll a (Chl‐a) were positively

In shallow coastal oceans, turbulent flows driven by surface winds and waves and constrained by a solid bottom disperse particles. This work examines the mechanisms driving horizontal and vertical dispersion of buoyant and sinking particles for times much greater than turbulent integral time scales. Turbulent fields are modelled using a wind‐stress driven large eddy simulation (LES), incorporating

Deep‐sea sponge grounds are hotspots of benthic biomass and diversity. To date, very limited data exists on the range of environmental conditions in areas containing deep‐sea sponge grounds and which factors are driving their distribution and sustenance. We investigated oceanographic conditions at a deep‐sea sponge ground located on an Arctic Mid‐Ocean Ridge seamount. Hydrodynamic measurements were

As the resolution of observations and models improves, emerging evidence indicates that ocean variability on 1–200‐km scales is of fundamental importance to ocean circulation, air‐sea interaction, and biogeochemistry. In many regions, salinity variability dominates over thermal effects in forming density fronts. Unfortunately, current satellite observations of sea surface salinity (SSS) only resolve

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Oceanography has entered an era of new observing platforms, such as biogeochemical Argo floats and gliders, some of which will provide three‐dimensional maps of essential ecosystem variables on the North‐West European (NWE) Shelf. In a foreseeable future operational centres will use multi‐platform assimilation to integrate those valuable data into ecosystem reanalyses and forecast systems. Here we

Lateral flows redistribute sediment and influence the morphodynamics of channel‐shoal systems. However, our understanding of lateral transport of suspended sediment during high and low water slack is still fairly limited, especially in engineered estuaries. Human interventions such as dike‐groyne structures influence lateral exchange mechanisms. The present study aims to unravel these mechanisms in

One‐dimensional vertical (1DV) diffusion‐settling models are practical tools for sediment transport analysis of sands, which is mostly a local process. However, for fine sediments, the observed concentrations C(t) can be mixed via horizontal advection (HA) due to the lower settling velocity, which makes the C(t) not necessarily a local process, thus making 1DV models invalid. It is important to determine

Knowledge of submonthly variability in ocean bottom pressure (pb) is an essential element in space‐geodetic analyses and global gravity field research. Estimates of these mass changes are typically drawn from numerical ocean models and, more recently, GRACE (Gravity Recovery and Climate Experiment) series at daily sampling. However, the quality of pb fields from either source has been difficult to

When evaluating the kinetic energy of the eddy field, using a flow‐decomposition method to split the eddies from the mean‐flow is often necessary. However, the kinetic energies of the eddy and mean‐flow may not sum up to the total energy, because of the existence of a third term, the residual kinetic energy (RKE). This paper attempts to thoroughly assess the RKE from both theoretical and observational

A Lagrangian plankton model (LPM) is developed, in which the motion of a large number of Lagrangian particles, representing a parcel of plankton, is calculated under the turbulence field simulated by large‐eddy simulation. A spring phytoplankton bloom is realized using the LPM, and the mechanism for its 1 generation is investigated. The criterion based on these results is proposed as , where δ E (=

The region between a shallow mixed layer and a deep isothermal layer resulting from salinity stratification is called a barrier layer (BL). Since BLs hinder the surface heat and momentum exchange with the ocean subsurface, they play an important role in air‐sea interaction. Synoptic features and formation of BLs and associated temperature inversions (TIs) in the Eastern Pacific Fresh Pool (EPFP) were

The South China Sea (SCS) is a region vulnerable to tropical cyclones (TCs). An array of moored current meters and meteorological buoys was deployed within major pathways of TCs across the slope of the northern shelf of the SCS from September 1, 2017 through September 30, 2018. Three TCs, Khanun, SonTinh, and Mangkhut, traversed by the storm‐monitoring array in October 2017, July, and September 2018

The North Atlantic Current is the major pathway for warm and saline water from the subtropics into the subpolar North Atlantic. Its main branch crosses 47°/48°N in the western North Atlantic basin and further north the Mid‐Atlantic Ridge (MAR) before entering the eastern subpolar basin where it partly feeds the subpolar gyre. To quantify the meridional exchange of water between the subtropical and

The physical characteristics of water masses in the Cilician Basin were analyzed based on recent, comprehensive in‐situ data. Nine seasonal cruises from June 2015 to November 2017 were carried out in an area located in the north‐eastern Levantine Basin between the coasts of Turkey and Cyprus. In this little studied area, the structure of the water column, its seasonal variability, and water formation

A numerical modeling sensitivity study is carried out within the Labrador Sea by varying the atmospheric conditions. From forcing NEMO simulations with five atmospheric products commonly used in ocean modeling (DFS5.2, ERA‐Interim, CGRF, ERA5, and JRA55‐do), we calculate the air–sea heat fluxes that occur over the Labrador Sea (2002–2015 annual‐average net heat flux: −53.4, −51.0, −46.6, −58.5, and

Major deep‐convection activity in the northwestern Mediterranean during winter 2005 triggered the formation of a complex anomalous deep‐water structure that substantially modified the properties of the Western Mediterranean deep layers. Since then, evolution of this thermohaline structure, the so‐called Western Mediterranean Transition (WMT), has been traced through a regularly sampled hydrographic

This paper summarizes the statistics of observations of wind and surface gravity waves in Long Island Sound, a large estuarine embayment in southern New England. We examine the relationship between significant wave height and wind speed and direction and show that the significant wave height and dominant period in western Long Island Sound have an asymmetric response to the wind direction. Waves are

Biogenic emissions of dimethylsulfide (DMS) are an important source of sulfur to the atmosphere, with implications for aerosol formation and cloud albedo over the ocean. Natural aerosol sources constitute the largest uncertainty in estimates of aerosol radiative forcing and climate and thus, an improved understanding of DMS sources is needed. Coral reefs are strong point sources of DMS; however, this

A new modeling methodology for ripple dynamics driven by oscillatory flows using a Eulerian two‐phase flow approach is presented in order to bridge the research gap between near‐bed sediment transport via ripple migration and suspended load transport dictated by ripple induced vortices. Reynolds‐averaged Eulerian two‐phase equations for fluid phase and sediment phase are solved in a two‐dimensional

Particle dynamics play significant roles in sedimentological and geomorphological processes as well as biogeochemical cycles in estuaries. We collected a suite of water samples from the North Passage of the Changjiang (Yangtze) Estuary during different tidal conditions in summer 2009 to observe variations in the particulate 234Th, 7Be, 210Pb, and 137Cs activities as well as in particle transport, deposition

The central Red Sea (CRS) has been characterized by significant eddy activity throughout the year. Weakened wintertime stratification contributes to enhanced vertical exchange. In winter 2014‐2015, an extended glider time series in the CRS captured this variability. Surface cooling and stronger winds resulted in deepening of the mixed layer (ML) to nearly 90 m. The vertical distributions of density

Arctic liquid freshwater content (FWC) influences both regional and large‐scale ocean dynamics and climate. In this paper the responses of Arctic FWC, sea surface height (SSH) and surface circulation to different atmospheric circulation modes and the impact of sea ice decline on these responses are investigated by using wind perturbation simulations. The responses are intensified by sea ice decline

Increasing organic carbon (OC) inputs from coastal erosion contribute to large uncertainties in carbon cycling in coastal seas. The abandoned Huanghe Delta (AHD) is a typical coastal erosion region, which transports large amounts of eroded sediments to the Chinese marginal seas (CMS, not including the South China Sea). Here we investigated the organic geochemical characteristics of sedimentary organic

The response of the ventilation of mode and intermediate waters to abrupt changes in the Southern Annular Mode (SAM) is examined by analyzing the ideal age in a global ocean‐sea ice model. The age response is shown to differ between the central Pacific Ocean and other basins. In the central Pacific there are large decreases in the age of subtropical mode and intermediate waters associated with a more

Coral reefs generate substantial volumes of carbonate sediment, which is redistributed throughout the reef‐lagoon system. However, there is little understanding of the specific processes that transport this sediment produced on the outer portions of coral reefs throughout a reef‐lagoon system. Furthermore, the separate contributions of currents, sea‐swell waves, and infragravity waves to transport

Linear stability analysis is re‐conducted to fully understand the geostrophic distribution of the different types of baroclinic instability (BCI) in the global oceans, their correspondence to the different vertical structures of the observed mesoscale eddies, and the properties and formation mechanisms of the instability waves. Four principal vertical types of BCI are identified, which are found to

Fixed acoustic Doppler current profiler (ADCP) velocity measurements are used to investigate headland vorticity generation and recirculation in ∼ 20 m depth around the small ( ∼ 1 km) central California headland Pt. Sal. To reduce vorticity estimation noise, velocities are reconstructed from the first two EOF modes representing ≈ 73% of the variance. Using fixed ADCPs, depth‐averaged vorticity is estimated

Two methods for the mapping of ocean surface currents from satellite measurements of sea level and future current vectors are presented and contrasted. Both methods rely on the linear and Gaussian analysis framework with different levels of covariance definitions. The first method separately maps sea level and currents with single‐scale covariance functions and leads to estimates of the geostrophic

We have generated a high‐resolution coral Δ14C record from the leeward side of the Big Island of Hawai’i in the subtropical North Pacific. The record spans 1947–1992, when the coral was collected, and includes a brief prebomb interval as well as the postbomb era. Mean prebomb (1947–1954) values average −55‰ (±1, SE of the mean) with a clear seasonal cycle. Values are less positive during winter when

Eastern Boundary Current Upwelling Systems are regions of elevated primary production and carbon export and thus play a central role in the global carbon cycle. In these regions, nutrient upwelling occurs in a narrow region close to the coast, but primary production and carbon export are typically observed across a broader region. The fact that productive waters reach the open ocean has important consequences

Ocean waves can spatiotemporally redistribute the momentum flux at the air‐sea interface, which varies with the sea state. Traditional atmosphere‐ocean coupled systems assume the ocean‐side stress (τoc) to be identical to the air‐side stress (τa); consequently, the role of ocean waves is neglected. In this study, the wave impacts on the air‐sea momentum flux are investigated based on 1‐year high‐resolution

Phytoplankton growth in the Indian Ocean is generally limited by macronutrients (nitrogen: N and phosphorus: P) in the north and by micronutrient (iron: Fe) in the south. Increasing atmospheric deposition of N and dissolved Fe (dFe) into the ocean due to human activities can thus lead to significant responses from both the northern and southern Indian Ocean ecosystems. Previous modeling studies investigated

High‐resolution temperature variation was examined about 40 days near the ocean bottom at 20 sites within an area of 110 × 120 km2 close to the continental margin of the northern South China Sea (depth ≈ 4,000 m). The monitoring depth (0.5 m above the bottom) was presumably within the lower part of the bottom mixed layer, compared to its median thickness of 63 m. At all sites, the bottom water had

This study presents recent observations to quantify oceanic heat fluxes along the continental slope of the Eurasian part of the Arctic Ocean, in order to understand the dominant processes leading to the observed along‐track heat loss of the Arctic Boundary Current (ABC). We investigate the fate of warm Atlantic Water (AW) along the Arctic Ocean continental margin of the Siberian Seas based on 11 cross‐slope

129I measurements on samples collected during GEOTRACES oceanographic missions in the Arctic Ocean in 2015 have provided the first synoptic 129I sections across the Eurasian, Canada and Makarov Basins. During the 1990s, increased discharges of 129I from European nuclear fuel reprocessing plants produced a large, tracer spike whose passage through the Arctic Ocean has been followed by 129I time series

Measurements of light scattering can be used to quantify the concentration and composition of oceanic particles, and resolve biogeochemical processes spanning different time and space scales. In this paper, we analyze the first dataset, collected over wide spatial scales in the Red Sea, of particulate scattering (), particulate backscattering (), particulate absorption and chlorophyll‐a concentration

The correct representation of the 18.61 year nodal tide is essential for an interpretation of the evolution of mean sea level, as errors cause misleading bias. The nodal tide is currently estimated by applying correction factors in harmonic analysis, which are derived from the equilibrium tide. From the equilibrium tide, correction values f for amplitude and u for phase are determined, which alter

The twin Sentinel‐1 (S1) satellites have been extensively acquiring synthetic aperture radar (SAR) data in the Arctic, providing the unique opportunity to obtain ocean dynamic parameters with both high spatial resolution and wide swath coverage in the Arctic Ocean. In this paper, we proposed a method for retrieving the ocean significant wave height (SWH) from S1 SAR data in horizontal‐horizontal (HH)

The 2012/2013 Ningaloo Niño induced a strong marine heatwave (MHW) event on Australia's North West Shelf (NWS) during the austral summer, starting in December 2012 and peaking in January and February 2013. A high‐resolution regional numerical model based on the Regional Ocean Modelling System (ROMS) was implemented to simulate the variability of the upper ocean temperature and ocean circulation and

The Kuroshio Current, a vigorous western boundary current in the Pacific, is responsible for bringing high temperature, high salinity, and phosphate‐rich open ocean water into the East China Sea (ECS) when it flows past Taiwan and generates a branch current, known as the Kuroshio Branch Current (KBC), which intrudes onto the continental shelf of the ECS. Based on observations and numerical modeling

Quantifying and forecasting the impact of boat traffic on the health of coastal ecosystems must account for the multiscale nature of the process: from minutes (individual wakes), to days (tidal phase), weeks, and longer (tide modulation, seasonal traffic). Direct numerical simulations covering all these scales are difficult, not in the least because specifying the vessel type and navigation characteristics

The vertical variability in the oxygen minimum zone (OMZ) in the eastern South Pacific (ESP; 0–40°S) is characterized by the influence of anticyclonic intrathermocline eddies (ITEs), which are subsurface‐intensified mesoscale features that are frequently generated in the coastal upwelling zone off Peru and Chile. The unique lens‐shaped signatures that ITEs leave on temperature, salinity, and dissolved

In the presence of a mean flow, theory and models for internal tide generation at small‐amplitude topography show (a) internal tides produce a net momentum flux that extends to the surface and (b) fluxes are directed preferentially upstream. Here, we observe internal tides propagating into the North Equatorial Countercurrent during two spatial surveys near a submarine ridge. On the second survey during

This study used high‐frequency acoustic instruments mounted on an offshore observation platform to obtain simultaneous in situ measurements of sea surface winds and ocean currents. The acquired data were used to compare quantitatively the turbulent Reynolds stress in the ocean surface boundary layer (OSBL) and the wind stress over the sea surface. During the study period (∼10 d), the sea state was

This paper examines the heat balance of the inner shelf along the U.S. West Coast using 14 years of summer temperature and velocity observations in 15 m water depth. Previous work at this site found no year‐to‐year variability in the observed mean summer temperature change despite significant warming due to surface heat flux and variable cooling due to across‐shelf heat flux. Here, the processes that

The effects of instrument noise on estimating the spectral attenuation rates of ocean waves in sea ice are explored using synthetic observations in which the true attenuation rates are known explicitly. The spectral shape of the energy added by noise, relative to the spectral shape of the true wave energy, is the critical aspect of the investigation. A negative bias in attenuation that grows in frequency

The China France Oceanography Satellite (CFOSAT) and Haiyang‐2B (HY‐2B) satellites were successively launched in China on the 29th and 25th of October 2018, respectively. HY‐2 B carries the second Chinese radar altimeter along with three other microwave sensors, whereas CFOSAT contains the first Surface Waves Investigation and Monitoring (SWIM) instrument and a fan beam rotating scatterometer. As missions

Volume, heat and freshwater transports from the South China Sea (SCS) to the Java Sea through the Karimata Strait are estimated based on direct measurements of current, temperature, salinity, and satellite observations. Subject to strong seasonal variability, the volume, heat, freshwater transports are −1.98 ± 0.23 Sv (1 Sv = 106 m3/s), −209.68 ± 15.19 TW (1 TW = 1012 W), −99.87 ± 15.11 mSv (1 mSv = 10‐3 Sv)

A realistic numerical model is used to study the circulation and mixing of the Salish Sea, a large, complex estuarine system on the United States and Canadian west coast. The Salish Sea is biologically productive and supports many important fisheries but is threatened by recurrent hypoxia and ocean acidification, so a clear understanding of its circulation patterns and residence times is of value.

The meridional variability of the Subtropical Front (STF) and the drivers of variability on interannual time scales in the New Zealand region are analyzed using a multi‐decadal eddy‐resolving ocean hindcast model, in comparison with Argo data. The STF marks the water mass boundary between subtropical waters and subantarctic waters, and is defined as the southern‐most location of the 11°C isotherm and

Advances in the understanding and modelling of surface currents have revealed the importance of internal waves, mesoscale and submesoscale features. Indeed all these features should have a large influence on wind waves and in particular on wave heights. Still, the quantitative impact of currents on waves is not well known due to the complexity of the random wave fields and currents that are found in

The genus Phaeocystis is distributed globally and has considerable ecological, biogeochemical, and societal impacts. Understanding its distribution, growth and ecological impacts has been limited by lack of extensive observations on appropriate scales. In 2018, we investigated the biological dynamics of the New England continental shelf and encountered a substantial bloom of Phaeocystis pouchetii.

Absorbance and fluorescence properties of dissolved organic matter (DOM) were measured in the upper and lower polar mixed layer (UPML and LPML, respectively) over an 11‐year period (2007–2017) to assess for yearly changes in the quality and quantity of colored and fluorescent DOM (CDOM and FDOM, respectively) in relation with sea ice concentration in central Canada Basin waters. The LPML waters were

Fifteen years of satellite observations of sea surface temperature (SST) are used to identify frontal activities in the eastern Pacific Ocean. The frontogenesis and variability of frontal activities are mainly determined by wind forces. Strong frontal activities are distributed mainly near the coast and decrease with increasing offshore distance. The seasonal cycle dominates the variability in the

The ocean circulation around and over the Seychelles Plateau (SP) is characterized using 35 months of temperature and velocity measurements along with a numerical model. The results here provide the first documented description of the ocean circulation atop the SP. The SP is an unusually broad (∼200 km), shallow (∼50 m) plateau, dropping off steeply to the abyss. It is situated in a dynamic location

An intercomparison between directional wave spectra derived from Sentinel‐1 Synthetic Aperture Radar (SAR) satellites and a WAVEWATCH III model hindcast in the wider Australian region is presented. The coastal buoy network around Australia is considerably sparse, and only a handful of buoy measurements exist in deeper oceans. National and regional scale wave models require validation and verification