Global Multi-Resolution Topography WMS Service

GMRT synthesis is a continuously-updated compilation of seafloor topography derived from multibeam bathymetry data. The synthesis began as the Ridge Multibeam Synthesis, was expanded to include multibeam bathymetry data from the Southern Ocean and now includes other bathymetry from throughout the global and coastal oceans.

It is maintained as a multi-resolution gridded digital elevation model of seafloor bathymetry to ~100 m spatial resolution, and is merged with ~100 m resolution land topography data from the Shuttle Radar Topography Mission (SRTM). In the oceans, multibeam data are merged with lower-resolution compilations including satellite predicted bathymetry (Smith & Sandwell), the International Bathymetric Chart of the Arctic Ocean (IBCAO), and the SCAR Subglacial Topographic Model of the Antarctic (BEDMAP).