Real-time sea-level gauge observations and operational oceanography

Theme issue ‘Sea level science’.-- 18 pages, 11 figuresThe contribution of tide-gauge data, which provide a unique monitoring of sea-level variability along the coasts of the world ocean, to operational oceanography is discussed in this paper. Two distinct applications that both demonstrate tide-gauge data utility when delivered in real-time are illustrated. The first case details basin-scale operational model validation of the French Mercator operational system applied to the North Atlantic. The accuracy of model outputs in the South Atlantic Bight both at coastal and offshore locations is evaluated using tide-gauge observations. These data enable one to assess the model's nowcasts and forecasts reliability which is needed in order for the model boundary conditions to be delivered to other coastal prediction systems. Such real-time validation is possible as long as data are delivered within a delay of a week. In the second application, tide-gauge data are assimilated in a storm surge model of the North Sea and used to control model trajectories in real-time. Using an advanced assimilation scheme that takes into account the swift evolution of model error statistics, these observations are shown to be very efficient to control model error, provided that they can be assimilated very frequently (i.e. available within a few hours)Part of this work was funded by the Marine Environment and Security for the European Area project (MERSEA) supported by the European Commission under the 6th framework programme. The other part was supported by Centre National Etudes Spatiales (CNES) and Centre National de la Recherche Scientifique (CNRS). The Florida Current cable data are made freely available on the Atlantic Oceanographic and Meteorological Laboratory web page (www.aoml.noaa.gov/phod/floridacurrent) and are funded by the NOAA Office of Climate ObservationsPeer reviewe

« La constitution des référentiels bibliques du projet Biblindex »

International audienceA dozen Bibles have been put into detailed correspondence by the SourcesChrétiennes team in the Biblindex database, book by book, verse by verse, even verse part by verse part.. Two issues have been overcome:differences between the canons (some books, chapters or verses arenot present in all versions, and / or appear in a different order); semanticdifferences from one version to another, which impact a book, a chapter, averse, or a verse part.Une douzaine de Bibles ont été mises en correspondance par l’équipe des SourcesChrétiennes dans la base de données de Biblindex, livre par livre, verset par verset, voire partie de verset par partie de verset. Deux difficultés ontdû être surmontées : les différences de canon, qui font que certains livres,chapitres ou versets ne sont pas présents dans toutes les versions, et/ouapparaissent dans un ordre différent ; les différences sémantiques d’une versionà l’autre, qui peuvent jouer à l’échelle du livre, du chapitre, du versetou de la partie de verset

International Workshop on Computer Aided Processing of Intertextuality in Ancient Languages (2-4 juin 2014, Lyon) : bilan et perspectives

International audienc

International Workshop on Computer Aided Processing of Intertextuality in Ancient Languages (2-4 juin 2014, Lyon) : bilan et perspectives

International audienc

« La constitution des référentiels bibliques du projet Biblindex »

International audienceA dozen Bibles have been put into detailed correspondence by the SourcesChrétiennes team in the Biblindex database, book by book, verse by verse, even verse part by verse part.. Two issues have been overcome:differences between the canons (some books, chapters or verses arenot present in all versions, and / or appear in a different order); semanticdifferences from one version to another, which impact a book, a chapter, averse, or a verse part.Une douzaine de Bibles ont été mises en correspondance par l’équipe des SourcesChrétiennes dans la base de données de Biblindex, livre par livre, verset par verset, voire partie de verset par partie de verset. Deux difficultés ontdû être surmontées : les différences de canon, qui font que certains livres,chapitres ou versets ne sont pas présents dans toutes les versions, et/ouapparaissent dans un ordre différent ; les différences sémantiques d’une versionà l’autre, qui peuvent jouer à l’échelle du livre, du chapitre, du versetou de la partie de verset

Inter-comparing five forecast operational systems in the North Atlantic and Mediterranean basins: The MERSEA-strand1 methodology

36th International Liege Colloquium on Ocean Dynamics MAY 03-07, 2004 Liege, BELGIUMInternational audienceThe methodology to achieve a real time inter-comparison of five state-of-the-art operational forecast systems for the North Atlantic and Mediterranean basins is presented. All systems provide analysis and near real-time prediction of the three-dimensional ocean through Opendap servers. A standard set of diagnostics called metrics, is described. Definition and examples of metrics are given. An inter-comparison of the five systems is conducted over a 1 year period using those metrics. It is shown that the methodology developed allows a successful inter-comparison. It has been adopted by the GODAE community. It is also shown that the systems are consistent with the current knowledge of the ocean circulation and climatologies. Systems are deficient in the representation of specific water masses characteristics as Mode waters. Data assimilation of vertical profiles of temperature and salinity solve such deficiencies. Metrics also allow a monitoring of the system's North Atlantic overturning stream function and will allow detecting any changes in the coming year system's thermohaline circulation

Aliasing inertial oscillations in a 1/6° Atlantic circulation model: impact on the mean meridional heat transport

A 1/6° model simulation of the Atlantic ocean forced with daily fluxes from ECMWF (re-analysis 1979–1993 and analysis 1994–1999) has been carried out within the Clipper project. A storage strategy which filters out inertial oscillations is defined: five-day mean fields are continuously stored at five-day intervals. It is shown that aliasing errors on the monthly mean meridional heat transport (MHT, a second-order moment) are negligible in that case. These errors are of the order of 0.8 PW in the tropics in the case of a sampling strategy based on instantaneous fields stored every five days, even in the case where step-like variations in the forcing are avoided by an interpolation of the daily wind stress to the model time step. It is also shown that aliasing errors on the annual mean MHT can be as large as 0.2 PW in the tropics in the case of sub-sampling with instantaneous fields

Modeling pseudo capacitance of manganese dioxide

International audienceIn order to better analyze and to explain the electrochemical and physical behavior during both charge and discharge of a manganese dioxide based ECs, an original electrochemical model is developed in this paper. The 1D model is an adaptation of the transmission line model (TLM), taking into account the cation diffusion in the solid oxide. A linear relation between redox potential and oxidation state is used and leads to a physical relation between its slope and the pseudo capacitance of the material, confirmed by an experimental investigation of cyclic voltammograms. The model can be applied for any metal oxide pseudo-capacitive material

Electrode Design for MnO2-Based Aqueous Electrochemical Capacitors: Influence of Porosity and Mass Loading

International audienceThe purpose of this study is to highlight the influence of some fabrication parameters, such as mass loading and porosity, which are not really elucidated and standardized during the realization of electrodes for supercapacitors, especially when using metal oxides as electrode materials. Electrode calendering, as one stage during the fabrication of electrodes, was carried out step-by-step on manganese dioxide electrodes to study the decreasing porosity effect on the electrochemical performance of a MnO2 symmetric device. One other crucial parameter, the mass loading, which has to be understood and well used for realistic supercapacitors, was investigated concurrently. Gravimetric, areal and volumetric capacitances are highlighted, varying the porosity for low-, medium- and large-mass loading. Low-loading leads to the best specific capacitances but is not credible for realistic supercapacitors, except for microdevices. Down 50% porosities after calendering, capacitances are increased and become stable faster, suggesting a faster wettability of the dense electrodes by the electrolyte, especially for high-mass loading. EIS experiments performed on electrodes without and with calendering lead to a significant decrease of the device’s time response, especially at high loading. A high-mass loading device seems to work as a power battery, whereas electrode calendaring, which allows decreasing the time response, leads to an electrical behavior closer to that expected for a supercapacitor