MARINEXPLORE.org is an Open Data Community for Ocean Professionals, currently (as of Aug 13, 2013) with 5,369 Professionals, 1,491,887,087 Point Measurements, 35,396 In-Situ Platforms, and 41 Gridded Data Sources.

A recent blog entry says that

Marinexplore now provides elevation data at 1 arc-minute global relief model of Earth’s surface from ETOPO1, integrating land topography and ocean bathymetry from global and regional datasets on a high resolution gridded product.

Marinexplore technology helps the offshore industry to reduce risk and cut data processing time five-fold.

Its spatio-temporal data platform is designed for secure data management and analytics on distributed sources, without ever having to relocate the data.

See marinexplore.org/.

Check also other Data APIs, Hubs, Marketplaces, Platforms, Portals, and Search Engines.