Marine sciences can benefit immensely from GIS, because these computer tools are designed to bring together spatial data from diverse sources into a unified database, often employing a variety of digital data structures, and representing spatially varying phenomena as a series of data layers, all of which are in spatial register, meaning that they overlap correctly at all locations.

Thus by manipulating maps, digital images and tables of geocoded (geographically located) data items, such as the results of oceanographic surveys, satellite images, seafloor mappings and biogeochemical studies in the open ocean GIS provides tools for analysing and modelling the interrelationships between these individual layers of spatial data.