Subsurface lagrangian tracking of profiling floats

The Office of Naval Research awarded Woods Hole Oceanographic Institution $650,000 on December 1, 2025, under the Basic and Applied Scientific Research program (CFDA 12.300) to develop, test, and deploy a passive acoustic system for subsurface Lagrangian tracking of profiling floats.

The work centers on integrating passive acoustic positioning technology into MRV Systems ALTO profiling floats rated to 2000 meters depth. The effort will employ the Woods Hole ACOMMS group's Low-Power Detector for passive positioning, combined with hydrophone and real-time clock integration. First-year activities focus on engineering and procurement of common components for two ALTO floats serving as test assets; subsequent years support field deployments, test events, float operations, and data analysis. The project incorporates lessons learned from prior Arctic deployments of the Woods Hole Micromodem2 on ALTO and S2-A floats, as well as successful integration of the DMON2 passive acoustic recorder for marine mammal research applications.

Woods Hole Oceanographic Institution, a private nonprofit oceanographic research organization headquartered in Woods Hole, Massachusetts, receives the award as the prime recipient. Performance occurs in Massachusetts.

MRV Systems, LLC, a San Diego–based manufacturer of oceanographic research equipment and autonomous marine technologies, is the sub-recipient. MRV will provide engineering design, sensor integration, and float procurement support under sub-award N000142612098-A101741, issued December 22, 2025.

The period of performance extends from December 1, 2025, through November 30, 2030.