ILICO, a French Research Infrastructure (RI) for Coastal Ocean and Nearshore Observations is a notable example of national and pan-institutional efforts to expand knowledge of the complex processes at work within the critical coastal zone in line with the European Ocean Observing System perspective. Providing a forum for its community to work together on priority issues is a challenge, and ILICO’s organizational structure and governance are designed accordingly. Future challenges for this RI include the question of whether France’s original model of combining both land and nearshore in its study of the coastal domain is transferable to the pan-European context and how far we can go in integrating overseas and ultramarine issues.

To understand and predict the physical, chemical, and biological processes at play in coastal and nearshore marine areas requires an integrated, interdisciplinary approach. The case study of the French structuration of coastal ocean and nearshore observing systems provides an original overview on a federative research infrastructure named ILICO. It is a notable example of national structuration and pan-institution efforts to investigate the forefront of knowledge on the processes at work within the critical coastal zone. ILICO comprises, in a pluridisciplinary approach, eight distributed network-systems of observation and data analysis that are accredited and financially supported by French research institutions and the French Ministry for Higher Education, Research, and Innovation. ILICO observation points are implemented along metropolitan and overseas French coasts, where coastline dynamics, sea level evolution, physical and biogeochemical water properties, coastal water dynamics, phytoplankton composition, and health of coral reefs are monitored in order to address a wide range of scientific questions. To give an overview of the diversity and potential of the observations carried out, this paper offers a detailed presentation of three constituting networks: Service Observation en Milieu LITtoral (SOMLIT), with homogeneous sampling strategies, DYNALIT, with heterogeneous sampling strategies adapted to different environments, and Mediterranean Ocean Observing System for the Environment (MOOSE), an integrated, pluri-disciplinary coastal/offshore regional observatory in the north-western Mediterranean Sea. ILICO was conceived using a European framework. It addresses the great challenges of the next decade in terms of sustainability, cost-efficiency, interoperability, and innovation. This paper emphasizes the added-value of federating these systems, and highlights some recommendations for the future.

There are two ways of assessing the costs of environmental degradation: as the costs associated with the loss of benefits resulting from the degradation of natural capital, and as the maintenance costs required to compensate for the actual or potential degradation of natural capital. The first of these methods is based on the Total Economic Value (TEV) of benefits forgone because of the depletion of ecosystem services delivered by marine biodiversity. The second method is based on the costs required to maintain a good state of marine biodiversity, one which makes it possible to deliver ecosystem services. This paper gives an illustration of this second approach. It details how these maintenance costs have been calculated in the initial assessment of the Marine Strategy Framework Directive (MSFD) in France. It addresses nine problem areas – corresponding to nine sources of environmental degradation – from non-native invasive species to oil spills. It gives a total figure for these degradation costs (around 2 billion Euros). The results are compared with those of other Member States who have taken similar approaches in the context of the MSFD. One key conclusion is that it is not really possible to make meaningful comparisons at this stage, since the methods of data collection and the nature of the costs are very different. The need to develop such assessments in a standardised way is noted.

Ce document presente la charte encadrant les travaux cartographiques a realiser pour l’evaluation initiale (Art. 8) de la directive-cadre « strategie pour le milieu marin »1 (DCSMM) a l’echelle des quatre sous-regions marines presentees dans la figure 1. Il est destine aux referents experts et aux coordonnateurs de l’evaluation initiale. La charte propose des mises en page harmonisees (taille, format, police, legende…) et preconise quelques elements de semiologie graphique pour la representation de certaines couches d’information geographique. Elle presente egalement un certain nombre de recommandations techniques pour l’utilisation du logiciel de cartographie et de l’information geographique. Les cartes creees serviront d'illustrations aux contributions thematiques des referents-experts et seront inserees dans les rapports finaux de chaque sous-region. De plus, les donnees ayant servi a l'elaboration de ces cartes seront si possible mises en ligne sur le serveur Sextant2, dote de fonctionnalites definissant les droits d'acces et autorisant la visualisation a des echelles differentes et a des emprises personnalisees. Sextant s'appuyant entre autre sur les technologies d'ArcGIS server, la charte cartographique decrite ici sera entierement respectee. Ce document est accompagne d’un dossier numerique contenant les fichiers a utiliser avec le logiciel ArcGIS (ESRI) : les projets au format «.mxd » et quelques couches d’information geographique utiles a l’exercice au format shapefile «.shp ». Des competences en geomatique et en cartographie sont indispensables pour la bonne comprehension du document et pour la realisation des cartes.

This paper presents the PREVIMER project which aims to provide a wide range and ever-growing number of coastal area users with observations, modelling tools and real-time forecasts, taking account of the statutory context. PREVIMER is based on observations and coastal ocean modelling. The www.previmer.org website displays forecasts for the French coastline of current strength and direction, wave height and direction, sea levels, storm surges, temperature, salinity, nutrients and phytoplankton concentrations. These data and their analyses will provide essential information for coastal zone usage or management. Cet article presente le projet PREVIMER qui a pour objectif de fournir les observations, les outils d’observation et de modelisation et les previsions en temps reel necessaires aux usagers des zones cotieres, toujours de plus en plus nombreux, en tenant compte du contexte reglementaire. Base sur l’observation et la modelisation, le site Internet www.previmer.org offre pour les cotes francaises les previsions sur la direction et l’intensite des courants, la hauteur, la frequence et la direction des vagues, les niveaux de la mer, les surcotes/decotes, la temperature et la salinite, la concentration en nutriments et en phytoplancton. Ces donnees et les analyses retrospectives vont devenir des outils essentiels pour la gestion et l’usage des zones cotieres.

This paper presents the PREVIMER project which aims to provide a wide range and ever-growing number of coastal area users with observations, modelling tools and real-time forecasts, taking account of the statutory context. PREVIMER is based on observations and coastal ocean modelling. The www.previmer.org website displays forecasts for the French coastline of current strength and direction, wave height and direction, sea levels, storm surges, temperature, salinity, nutrients and phytoplankton concentrations. These data and their analyses will provide essential information for coastal zone usage or management. Cet article présente le projet PREVIMER qui a pour objectif de fournir les observations, les outils d'observation et de modélisation et les prévisions en temps réel nécessaires aux usagers des zones côtières, toujours de plus en plus nombreux, en tenant compte du contexte réglementaire. Basé sur l'observation et la modélisation, le site Internet www.previmer.org offre pour les côtes françaises les prévisions sur la direction et l'intensité des courants, la hauteur, la fréquence et la direction des vagues, les niveaux de la mer, les surcotes/décotes, la température et la salinité, la concentration en nutriments et en phytoplancton. Ces données et les analyses rétrospectives vont devenir des outils essentiels pour la gestion et l'usage des zones côtières.

A high-resolution survey was conducted as part of the 2001 Programme Ocean Multidisciplinaire Meso Echelle (POMME 2) experiment in a region of the northeast Atlantic Ocean characterized by a large number of strongly interacting mesoscale eddies. The survey was located between mesoscale eddies in an area where the horizontal stirring processes were dominant. Diagnosis, using SeaSoar data combined with the analysis of altimeter data, reveals an energetic vertical velocity field involving elongated thin structures with alternate signs and amplitude up to 20 m day 1 . The 3D dynamics involved in the appearance of these vertical motions is the restoration of the thermal wind balance within the small-scale density filaments that are elongated by the stirring processes. These experimental results reinforce the conclusions of previous numerical studies pointing out the necessity to explicitly include the effects of the filamentation process in ocean models.

Abstract A high-resolution survey was conducted as part of the 2001 Programme Ocean Multidisciplinaire Meso Echelle (POMME 2) experiment in a region of the northeast Atlantic Ocean characterized by a large number of strongly interacting mesoscale eddies. The survey was located between mesoscale eddies in an area where the horizontal stirring processes were dominant. Diagnosis, using SeaSoar data combined with the analysis of altimeter data, reveals an energetic vertical velocity field involving elongated thin structures with alternate signs and amplitude up to 20 m day−1. The 3D dynamics involved in the appearance of these vertical motions is the restoration of the thermal wind balance within the small-scale density filaments that are elongated by the stirring processes. These experimental results reinforce the conclusions of previous numerical studies pointing out the necessity to explicitly include the effects of the filamentation process in ocean models.

Conducted in the northeast Atlantic Ocean (15°20′–21°20′W, 38°N–45°N), the Programme Océan Multidisciplinaire Méso Echelle (POMME) is a research project aimed at a better understanding of the biological production and the carbon budget of the region in relation to the formation mechanisms of the 11°–12°C mode water of the northeast Atlantic. With the help of two research vessels, several tens of floats and drifters, and nine moorings, the field experiment was carried out between autumn 2000 and autumn 2001, with a more intensive phase in the winter and early spring of 2001. The field experiment resolved small (several kilometers) to regional (several hundred kilometers) scales and daily to seasonal variability. A first analysis of the rich data set focused on the large‐scale and the mesoscale variability. It shows that the distribution of water mass characteristics and biological activity is strongly influenced by the mesoscales in this supposedly quiet transition zone between the subtropical and subpolar gyres. The seasonal variability, however, presents an imprint of the large‐scale structures with a clear north‐south gradient in properties and budgets. This region is found on an annual average to be a sink of atmospheric CO2. Smaller scales, associated with fronts and filaments, were clearly observed in many fields (temperature, but also chlorophyll, oxygen, biogenic particles, etc.), with modeling studies suggesting that they play a significant role in subduction, ventilation, and transport of biogeochemical tracers in the POMME region.

Abstract A meddy was discovered in April 1997 off the northwestern corner of Spain, near 45°N, 11°30′W. It was tracked during 18 months with Lagrangian floats and deep drogued buoys, and several cruises were set to collect further hydrological and Lowered-ADCP measurements on it. The meddy, named Ulla, was a one-core lens with maximum values of temperature and salinity of 11.5°C and 36.17 psu near 1000-m depth, yielding anomalies above 2.5°C and 0.5 psu compared to its environment. Its rotation frequency was close to 1 loop every 5 days. The maximum azimuthal velocities of 15–20 cm s−1 were reached near a 15-km radius. The meddy had a wide remote influence, notably up to the surface, and was associated with a total azimuthal volume transport of around 10 Sv, (Sv = 106 m3 s−1), of which around 2 Sv was trapped in the core. A widening of the radial structure with decreasing depth was notable in August 1997. Meddy Ulla was significantly elliptic for most of the time and, depending on the periods, the main el...

Hydrological measurements made in July 1999 in the Gulf of Cadiz reveal the presence of two meddies, one south of Cape Saint Vincent (meddy Christine, centered at 9°45′W–35°30′N), the other one near the Moroccan shelf (meddy Isabelle, centered at 8°30′W–34°25′N), and their interaction with a deep cyclone (centered at 8°30′W–35°15′N). These meddies are medium-scale features with thermohaline anomalies of 60–70 km diameter concentrated between 750 and 1500 m depths; these anomalies reach 2 °C and 0.5 in salinity. Meddy Christine exhibits unusually strong thermohaline gradients at its periphery. Their maximum azimuthal velocities are 0.12 m/s (meddy Isabelle) and 0.10 m/s (meddy Christine). They both have a (vertically) tripolar structure in potential vorticity anomaly. The cyclone is shallower (between 600 and 1300 m) with a weaker signature of Mediterranean water (12 °C at 800 m, 36.2 in salinity between 800 and 1200 m). Its velocity maximum (0.16 m/s) is also centered near 800 m. This cyclone appears coupled with meddy Isabelle as a baroclinic dipole. This dipole tears a long warm and salty filament away from meddy Christine at 1200 m. The long-term evolution of these eddies is described by means of deep-drogued drifting buoy trajectories: while meddy Christine drifts southwestward, the two other eddies remain close to each other and move together along the continental shelf towards Cape Saint Vincent where they separate. A three-layer quasi-geostrophic model is used to evaluate the possible origin of meddy Isabelle and of the cyclone near the Portuguese coast, and to assess if their interactions, both mutual, with the domain boundaries, and with bottom topography, can account for their motion. The interaction of this dipole with meddy Christine is also quantified in this model.

Within the Central waters of the North Atlantic Ocean there is a significant east–west difference in salinity, similar to that caused by Mediterranean Water at deeper levels. In this paper we hypothesize that the salinity of the Central Water is influenced by the saline Mediterranean Outflow Water, despite physical separation of the two water masses by a salinity minimum over most of the ocean basin. It is suggested that there occurs a cross-isopycnal flux of salinity from the Mediterranean Outflow Water towards the low-density Central Water (detrainment) in the eastern Gulf of Cadiz, not far from the Strait of Gibraltar, where the two water masses are in physical contact. Laboratory experiments, inverse modeling and direct current observations are applied to support the hypothesis.

Southwest of Portugal, in situ data show that part of the mesoscale variability of the Mediterranean Water undercurrents is triggered by topographic effects (near capes and submarine canyons), and is driven by a dominantly baroclinic instability. The vertical alignment of these undercurrents observed at sites of eddy formation is indeed favorable to baroclinic instability. This instability is materialized by the formation of filaments and of small eddies in the Portimão canyon and of meddies near Cape Saint Vincent and near the Estramadura Promontory. Hydrological data and float trajectories reveal that these eddies have a baroclinic structure. Near Portimão canyon, the variation of the potential vorticity of the undercurrents again proves their sensitivity to baroclinic and also to barotropic instabilities, enhanced by the canyon. Finally, a model of stationary coastal current explains the variations of its horizontal structure over a canyon. © 2000 Ifremer/ CNRS/IRD/Éditions scientifiques et médicales Elsevier SAS Résumé – Instabilité des sous-courants d’eau méditerranéenne au sud-ouest du Portugal : effets conjoints de la baroclinicité et de la topographie. Au sud-ouest du Portugal, des données in situ montrent qu’une partie de la variabilité méso-échelle des sous-courants d’eau méditerranéenne est déclenchée par des effets topographiques au voisinage des caps et des canyons sous-marins et est générée par une instabilité essentiellement barocline. L’alignement vertical de ces sous-courants, observé aux sites de formation de tourbillons, est en effet favorable à l’instabilité barocline. Cette instabilité est matérialisée par la formation de filaments et de petits tourbillons lenticulaires dans le canyon de Portimão, et de ‘‘meddies’’ au cap Saint Vincent et près du promontoire d’Estrémadure. Les données hydrologiques et les trajectoires de flotteurs lagrangiens révèlent que ces tourbillons ont une structure barocline. Près du canyon de Portimão, la variation de la vorticité potentielle des souscourants montre leur sensibilité à l’instabilité barocline, et également barotrope, amplifiées par le canyon. Enfin, un modèle de courant côtier stationnaire permet d’expliquer ses variations de structure horizontale sur un canyon. © 2000 Ifremer/CNRS/IRD/Éditions scientifiques et médicales Elsevier SAS Mediterranean Water / undercurrents / baroclinic instability / meddies / NE Atlantic Eau méditerranéenne / sous-courants / instabilité barocline / ‘‘meddies’’ / Atlantique nord-est * Correspondence and reprints: xcarton@ifremer.fr (X. Carton). © 2000 Ifremer/CNRS/IRD/Éditions scientifiques et médicales Elsevier SAS. PII: S0399-1784(00)01105-1/FLA L. CHERUBIN et al. / Oceanologica Acta 23 (2000) 551–573

Southwest of Portugal, in situ data show that part of the mesoscale variability of the Mediterranean Water undercurrents is triggered by topographic effects (near capes and submarine canyons), and is driven by a dominantly baroclinic instability. The vertical alignment of these undercurrents observed at sites of eddy formation is indeed favorable to baroclinic instability. This instability is materialized by the formation of filaments and of small eddies in the Portimao canyon and of meddles near Cape Saint Vincent and near the Estramadura Promontory. Hydrological data and float trajectories reveal that these eddies have a baroclinic structure. Near Portimao canyon, the variation of the potential vorticity of the undercurrents again proves their sensitivity to baroclinic and also to barotropic instabilities, enhanced by the canyon. Finally, a model of stationary coastal current explains the variations of its horizontal structure over a canyon. (C) 2000 Ifremer/CNRS/IRD/Editions scientifiques et medicales Elsevier SAS.

We describe the properties and displacement of the northernmost Meddy that has ever been studied. This Meddy was found to the northwest of the Iberian Peninsula in April 1997. Its hydrological properties suggest that it was born offshore Galicia, the northwestern corner of Spain. It was tracked in real‐time for more than one year using recent types of deep drogued buoys and Lagrangian floats, and remained quasi‐stationary for an unusually long period of 11 months around 45°N, 12°W.

A set of 102 high-resolution hydrographic lines (mostly XBT lines) in the eastern North Atlantic is used to study baroclinic vortices dynamically intensified within the Central Water layer. First, for the sake of comparison with recent results from altimetry, spatial statistics of the main thermocline dynamic height are computed. The dynamic height wavenumber spectrum slope (close to k(-3) at wavelengths shorter than 300 km), and the decrease with latitude of eddy scales deduced from its autocorrelation function, are found to be consistent with previous, local altimetric results.Then, using a criterion of local temperature anomaly relative to the large-scale trend along each line, 162 Central Water mesoscale vortices are detected. Their distribution is heterogeneous, vortices of different size, sign, and intensity being found in most places. They have a mean apparent diameter (chord along the line) of 110 +/- 50 km. It is estimated that a range of 100-145 Central Water vortices coexist at the same time between 20 degrees N and 55 degrees N, east of 34 degrees W. Statistics of their location are consistent with previous observations suggesting that instability of the North Atlantic Current, of the Azores Current, and of the poleward eastern boundary current are the major formation processes for these vortices. The latter process is thought to account for the higher total number of anticyclones (87) than of cyclones (75), and for the eastward decrease of the mean vortex diameter. There is, on the other hand, no clear correlation between vortex size and latitude or local internal Rossby radius, contrarily to what scales of the general eddy variability show. Statistics of several other hydrological and dynamical properties of the vortices are briefly discussed. Finally, the eddy kinetic energy at 100-m depth associated with the field of vortices is crudely estimated, and found to amount to around half of the total observed eddy kinetic energy. These findings are compared with results from theory, models, and altimetry.

The spreading of Labrador Sea Water (LSW) in the eastern North Atlantic south of 55°N is described on the basis of recent, high‐resolution hydrographic lines and using an inverse model of that basin general circulation. The isopycnic “salinity anomaly” relative to a standard θ/S curve is used to detect the main branches and limits of dominant influence of the intermediate water masses. The LSW crosses the Mid‐Atlantic Ridge at latitudes around 50°N with parts spreading farther eastward and southward. One southward pathway along the eastern side of the Mid‐Atlantic‐Ridge stands out as an eastern basin counterpart of the western Atlantic “Deep Western Boundary Current.” An entry into the Bay of Biscay in its northern part is also evidenced with striking similitudes between two data sets from 1974 and 1989–1990. At the southern limit of the LSW extension, in the vicinity of the Azores‐Biscay Rise, a marked front exists basinwide around 1800 m with the more saline Deep Mediterranean Water (DMW). The inverse model velocity field is consistent with most features of the tracer distributions and allows estimation of LSW transports: 6.3±1.2 Sv of LSW with salinities lower than 34.94 cross the 35°W meridian eastward between 44°N and 54°N, one fourth of which recirculates southwestward in the western basin, while another fourth turns northward across 54°N and the remaining half proceeds southward in the eastern basin. The model circulation suggests that DMW results from mixing between eastern basin LSW and the overlying Mediterranean Outflow Water, most probably through double diffusion. We finally describe several mesoscale structures of anomalously high LSW influence south of the LSW‐DMW front, notably one sampled by a RAFOS float. The velocity and potential vorticity fields suggest that these “LSW‐eddies” are formed through baroclinic instability at the LSW‐DMW front.

An inverse model is applied to a set of high-quality hydrographic measurements gathered between 1981 and 1993 in the eastern North Atlantic, between 24 degrees N and 54 degrees N and east of 35 degrees W. The method seeks a density field as close as possible to the hydrographic data and an absolute velocity field in exact geostrophic and hydrostatic balances, satisfying as well as possible the planetary vorticity balance, the Ekman dynamics at the surface and mass, salt and heat conservations in a top-to-bottom integrated form. A solution is found that departs only slightly from the hydrographic data and that presents reasonably small constraint residuals. The solution is discussed in terms of the eastern North Atlantic general circulation and thermocline ventilation during the observational period.The North Atlantic Current appears to be composed of several branches, and its influence extends down to more than 2500 m. Two-thirds of its total transport recirculates northward across 54 degrees N. The Azores Current appears as an almost zonal current around 33 degrees N that, while recirculating southward, is fed from the north by the southward recirculation of the North Atlantic Current. The total eastward transport of these two currents above the Mid-Atlantic Ridge amounts to 58 +/- 11 Sv, far more than predicted using the Sverdrup relation, and more than most of the previous estimates. It is shown that the interaction between the deep circulation and the bottom topography allows such a transport to be compatible with the planetary vorticity balance.Using the modeled circulation, thermocline ventilation is thoroughly studied. The subduction rate patterns show where the lightest varieties (27.0 < sigma(theta) <27.4) of Subpolar Mode Water (SPMW) are mainly formed and subducted. A total of 11.9 +/- 0.5 Sv of SPMW formation is estimated in the modeled area, while the total subduction transport amounts to 7.7 +/- 0.5 Sv, of which 2.5 +/- 0.4 Sv is SPMW subduction. Eddy diffusion along the isopycnals is estimated as playing no important role in SPMW subduction and in the first stages of its subsequent southward transport, but seems to be the dominant process by which that water crosses the Azores Front south of 36 degrees N. The Lagrangian, annual buoyancy budget of the winter mixed layer is finally diagnosed from the model fields, and it is confirmed that SPMW is formed where the mixed-layer loses buoyancy, and subducts as soon as the mixed layer gains buoyancy. (C) 1997 Elsevier Science Ltd.