In operational oceanography, regional and local models use large-scale models (such as those run by CMEMS) for their initial and/or boundary conditions, but unfortunately there is no feedback that improves the large-scale models. The present study aims at replacing normal 2-way nesting by a data assimilation technique. This upscaling method is tried out in the North-Western Mediterranean Sea using the Nemo model, and shows that the basin-scale model indeed benefits from the nested model.

This study uses different in-situ and satellite measurements to investigate the ocean circulation in the NW Mediterranean Sea. We analyze how the different instruments (satellite altimetry, HF radars, gliders, ADCPs) capture the current variability and how they complement each other. We demonstrate the ability of satellite altimetry to capture the fluctuations of the narrow coastal Northern Current at different time-scales. This study provides an integrated approach to a coastal dynamics study.

This work fully describes all the technical steps that are currently put in place in the context of the European Copernicus Marine Environment and Monitoring Service to make Ocean Colour data freely available to the general public. These data are useful for mapping the phytoplankton dynamics on daily and basin scale. The multi-sensor output well compares with data collected during dedicated field cruises proving that the operational product can be successfully used for environmental monitoring.

Sei whales are one of the least known baleen whales. We found them in southern Chile, on the Patagonian coasts. There we sailed on 2016 and 2017 to set hydrophones up in The Penas Gulf, to investigate how this Patagonian sei whales might be communicating. We could identify sei whale’s downsweeps calls (a type of vocalization that starts at a high frequency and ends at a lower). We found that sei whales at Penas Gulf perform calls distinctly differ from sounds previously described.

In our manuscript, new versions of simplified mathematical description (parameterization) of light absorption coefficients by phytoplankton suspended in surface layer of the Baltic Sea in relation to chlorophyll a concentration and concentration of accessory pigments are presented. The practical value of the simple parameterizations presented in this work should be seen in the opportunities for applying them to the development of remote sensing methods.

In a double tide the ocean reaches high or low tide, starts to fall or rise, only to go back to a new high or low. Here, we describe three ways this can happen by dividing locations with observed double tides into three classes. This showed that double tides are more common than we thought, and more complicated than most textbooks claim because they only describe one class of double tides. This matters to shipping, coastal flood management, and other disciplines interested in sea-level change.

This paper is motivated by the next SWOT altimetric mission dedicated to the observation of meso and submesoscale oceanic features. It focuses on tropical area where it exists a strong discrepancy in their spectral signature between altimetry and models. The paper review the spectral signature of tropical turbulence that present a rich variety of phenomenons depending on the latitudinal dependance of the Coriolis force. Internal tides observed by altimetry explain the discrepancy with the model.

We found that refining the spatial resolution of nitrogen deposition data had low impact on marine nitrogen compounds compared to the impact by nitrogen deposition data sets of different origin (other model). The shipping sector had a contribution of up to 10 % to the marine dissolved inorganic nitrogen.

Time-series observation can reveal processes and controlling factors underlying production and loss of iodocarbons in the ocean and provide data for testing hypotheses/models. Here, we report weekly observations of iodocarbons from May 2015 to Dec. 2017 at 4 depths in Bedford Basin, Canada. Iodocarbon in near-surface waters showed strong seasonal variability and similarities and differences in their correlation with temporal variations of potentially-related properties and causal factors.

Drag coefficient is not a constant because it is an increasing function of wind speed so we chose to check the differences between the relevant parameterizations for drag coefficient for momentum transfer values in the North Atlantic and the European Arctic. We show that the choice of drag coefficient parameterization can lead to significant differences in resultant momentum flux (or wind stress) values. The differences between the highest and lowest parameterizations may be 14 % in the Arctic.

The paper explored applicability of Landsat OLI sensor for monitoring concentration and movement of suspended particles along coastal landscape of Thiruvananthapuram. Suspended sediments moved north-south during post monsoon and reversed their direction during post monsoon season under the influence of monsoon winds. The findings revealed that the sediment concentration decreased rapidly with the increase in distance to the beach and depth to the seabed.

Ocean tides and mean sea level (MSL) can show correlations of short-term variability in addition to the long term trends, which may combine to increase total water levels at multiple time scales. Such changes may have implications for short-term high-water events such as nuisance flooding. This work analyzes the variability of tides in the Hong Kong region to find that small changes in MSL may amplify tidal changes in Hong Kong, suggesting a strong sensitivity of water levels in the region.

Understanding the role of ocean currents in the recruitment of commercially important fish is an important step toward developing sustainable resource management guidelines. Here, we attempt to elucidate the role of surface ocean transport in supplying recruits of European sardine to the Gulf of Manfredonia, a known recruitment area in the Adriatic Sea. We find that transport to the Gulf of Manfredonia from remote spawing areas in the Adriatic is more likely than local spawning and retention.

This paper deals with the quantification of the vertical transfers of heat, salt and mass between the inflowing and outflowing layers at the Strait of Gibraltar from the outputs of a very high spatial resolution numerical model. As a novelty, the model is not only forced by realistic barotropic tides, but also by the atmospheric pressure and heat and water fluxes at the sea surface. This fact allows a realistic representation of the exchanges at the Strait.

Using a regional model of the northwestern North Atlantic shelves, we calculate transport timescales and pathways in order to understand the transport processes that underlie the rapid oxygen loss, air–sea CO₂ flux, and supply of plankton seed populations on the Scotian Shelf. Study results highlight the limited connectivity between the Scotian Shelf and adjacent slope waters; instead, the dominant southwestward currents bring Grand Banks and Gulf of St. Lawrence waters to the Scotian Shelf.

Tide predictions based on tide-gauge observations are not just astronomical tides, they also contain periodic sea level changes due to the weather. Forecasts of total water level during storm surges add the immediate effects of the weather to the astronomical tide prediction, so must be careful not to double-count these effects. We calculate how much double-counting may affect these forecasts, and also how much of the Highest Astronomical Tide may also be due to recurrent weather patterns.

The primary aim of the study is to estimate wave energy attenuation by mangrove vegetation using SWAN model, and validate the model results with measurements for the Mumbai coastal region. Wave measurements presents wave height attenuation of the order of 52 %. Spectral analysis performed for the cases with and without vegetation very clearly portrays energy dissipation in the vegetation area. The model reproduced attenuation, ranging from 49 to 55 %, which matches well with the measured data.

A new concept of two types of marine geoid and associated absolute dynamic ocean topography is presented. The first type is the average level of sea surface height if the water is at rest (classical). The second type is determined by satellite observation under the condition that usually the water is in motion. The difference between the two types of absolute dynamic ocean topography is evident. Such difference needs attention from oceanographic and geodetic communities.