Weather forecasting models are used to show atmospheric conditions by computing changes in meteorological parameters on a 3D atmospheric grid model. Physical laws are used to determine behaviour: fluid mechanics, variation in water phase, turbulence, radiation, and atmospheric interaction with space, the continents and the oceans. The initial conditions are determined by assimilating variational data including a large volume and wide variety of in situ observations obtained from remote detection systems. The weather forecasts available on data.shom.fr only contain "wind at 10m" and "atmospheric pressure at sea level" parameters. A land/sea mask is then applied to exclude non-maritime forecasts. These forecasts are taken from 2 different types of models: ARPEGE for world and European scale input (0.5° to 0.1° resolution) and AROME for mainland France (1.3 km resolution). ARPEGE is a global hydrostatic spectral model, with variable horizontal resolution (centred on France), vertical finite element modelling and hybrid vertical coordinates. ARPEGE is an integral part of the Arpège-IFS software package, designed, developed and maintained by Météo-France in cooperation with ECMWF (European Centre for Medium-Range Weather Forecasts - http://www.ecmwf.int/). AROME is a non-hydrostatic spectral model for weather forecasts in mainland France, with finite difference modelling for vertical input and hybrid coordinates. AROME was developed by Météo-France thanks to close national (CNRS) and international (CEPMMT, Aladin, Hirlam) cooperation programmes on the basis of the Méso-NH research model and the dynamic core of the Aladin model.

These maps are prepared on the basis of vector-based mapping data (IHO S-57 format) including the detailed description of each object (beacons, wrecks, submarine cables, regulated zones, survey systems, etc.). These maps are the digital equivalent of printed nautical charts.

This product shows the international distribution of types of tides. Four types of tides exist, and are classified based on the number and height of high and low waters each day: semi-diurnal tide: two high tides and two low tides with approximately the same height are recorded each day. Mixed tides with diurnal inequality: two high and low tides are recorded daily (just like with semi-diurnal tides), however the heights of the high and low waters vary significantly over the same day. Diurnal tides: one single high tide and one single low tide are recorded each day. Composite: tides can be diurnal or semi-diurnal or mixed.

Non-georeferenced digital images in JPEG2000 format from former hydrographical survey fair sheets obtained from Shom's historical archives.

Marine toponymy data layer obtained from French ENC and created using the S23 (4th edition, June 2002). Note: The usual Sea of Japan designation does not imply taking a stand in the dispute between Korea, which names this sea "East Sea", and Japan, which names it "Sea of Japan".

Les modèles de prévisions de vagues permettent de représenter les états de mer au large, à l'échelle globale ou à celle des bassins océaniques en se basant sur une résolution spectrale. Ce code calcule l'évolution de l'état de la mer en le décomposant en un spectre d'onde se propageant dans différentes directions et avec différentes périodes T. Au cours de la propagation, l'énergie des vagues est augmentée ou diminuée par les effets du vent, du déferlement et les échanges d'énergie entre les différentes composantes. Les prévisions de vagues présentées sur data.shom.fr sont issues de 2 types de modèles différents : MFWAM pour le domaine hauturier (résolution de 0.5° à 0.1°) et Wave Watch 3 (WW3) pour le domaine côtier (résolution de 2min à 200m). MFWAM est un modèle de prévision des états de mer (mer du vent et houles) dérivé du code WAM de troisième génération (WAMDI Group, 1988). Wave Watch 3 (WW3) est développé dans le cadre d'une collaboration entre le service météorologique des Etats-Unis (NOAA/NCEP), le Shom, l'Université de Darmstadt en Allemagne, ainsi que d'autres partenaires. Les prévisions diffusées sur data.shom.fr sont issues du paramétrage réalisée et optimisé par le Shom et Météo-France dans le cadre de la vigilance Vagues-Submersions (VVS).