DARPA has awarded a contract for the next phase of development of its Ocean of Things (OoT), a project to seed the seas with thousands of floating sensors, monitoring everything that passes from aircraft to submarines.

The name is a play on the Internet of Things and the aim is to achieve persistent maritime situational awareness over large ocean areas. While satellites can provide some information, DARPA project manager John Waterson points out that there are gaps in their coverage – optical satellites cannot see through clouds, radar satellites only have limited coverage, and none of them can say much about what is going on underwater.

Floating sensors, known as floats, can gather far more detailed information, and can remain at sea for months at a time. There is a network of almost 4,000 Argo science floats around the world, gathering data on ocean temperature and salinity. Waterson wants to see much larger arrays of low-cost floats with more sensors, floats which would carry out missions lasting up to a year before scuttling themselves and degrading. The floats are environmentally friendly, avoiding the use of toxic materials.