Description of data processing :

No harmonisation of vertical datum have been applied when merging data sources (compatibility with Sea Level in a few tens of cm near)).

Source data received from data owners were DTM in GRID format (raster format ArcGis, structured in a matrix regular bathymetry associated with the centre of the cell of two types of format (raster format of ArcGis) with different resolutions. From each grid, we obtained a point SHAPE file, each point corresponds to the centre of the cell on the grid. Each point has the depth value of each cell. With each point SHAPE file, we use de command IDW (ArcGis) to realize an IDW Interpolation, (assigning weight in function of inverse of the distance). We have worked with the number of points that produced less error, in each case.When the DTM is composed by several grids with MOSAIC command of ArcGis, never these grids are intersecting between them; the grids are adjacent with a small zone of intersection to avoid the appearance of holes.

Description of processed data sources :

This DTM has been elaborated from several grids (ArcGis raster format), both treated with the IDW method.

These are a grid of 25 x 25 meters of resolution derived from a MBES SIMRAD 1000 survey with information about continental shelf and slope. The depths are between 5 and 160 meters.

The vertical datum is the zero of the patron port of Malaga (in Alboran W).

This information has been obtained in the ESPACE project. Spanish Institute of Oceanography.