Data Centre for French Coastal Operational Oceanography

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The Western Mediterranean Deep Water: A proxy for climate change

[ 1] Reconstructions of Mediterranean ocean temperature fields back to 1950 show a proxy relationship between heat content changes in the North Atlantic and the Western Mediterranean Deep Water ( WMDW) formed in the Gulf of Lions in winter, because of consistent air-sea heat fluxes over these areas, strongly correlated to the North Atlantic Oscillation ( NAO)

High-resolution Climatology of the northeast Atlantic using Data-Interpolating Variational Analysis (DIVA)

Numerous climatologies are available at different resolutions and cover various parts of the global ocean. Most of them have a resolution too low to represent suitably regional processes and the methods for their construction are not able to take into account the influence of physical effects (topographic constraints, boundary conditions, advection, etc.). A high-resolution atlas for temperature and salinity is developed for the northeast Atlantic Ocean on 33 depth levels. The originality of this climatology is twofold: (1) For the data set, data are collected on all major databases and aggregated to lead to an original data collection without duplicates, richer than the World Ocean Database 2005, for the same region of interest. (2) For the method, climatological fields are constructed using the variational method Data-Interpolating Variational Analysis. The formulation of the latter allows the consideration of coastlines and bottom topography, and has a numerical cost almost independent on the number of observations. Moreover, only a few parameters, determined in an objective way, are necessary to perform an analysis. The results show overall good agreement with the widely used World Ocean Atlas, but also reveal significant improvements in coastal areas. Error maps are generated according to different theories and emphasize the importance of data coverage for the creation of such climatological fields. Automatic outlier detection is performed, and its effects on the analysis are examined. The method presented here is very general and not dependent on the region, hence it may be applied for creating other regional atlas in different zones of the global ocean

Tsunami Deposits and Their Morphological Effects: A Regional Scale Approach

Tsunami are high energy events which have heavy morphological impacts on the shore lines. A review of the literature shows that these impacts are very difficult to differentiate from large storms impacts in most of the cases. This paper begins with a description of tsunami impacts, at a local scale, in terms of erosion and of accumulation. It studies cases where tsunami accelerate “normal” behaviour of the coast or, on the other hand go against expected normal behaviour. In order to better understand the relative roles of tsunamis and storms, the local forms are replaced within a regional scale/context and some important regions (Mediterranean Sea, New Zealand, the Antilles) are taken as examples of the interrelation between storm-forced evolution and tsunami – controlled behaviour