DURIP Integrating acoustic sensors onto microstructure EM-Apex Profiling Floats for the ONR DRI Experiment RIOT
Abstract
APPROVED FOR PUBLIC RELEASEWe propose to purchase ten EM-Apex floats and equip them with microstructure sensors and acoustic modemsfor the ONR DRI RIOT experiment, to perform underwater tracking and sampling of interior ocean trajectories. The floats will be purchased from Teledyne Webb Research (TWR), with the microstructure and acoustic systems being assembled, calibrated, and tested at APL-UW. The proposal covers development work to integrate the acoustic modems (the Micro Modem, made by WHOI) into the present EM-Apex design, including an iso-surface sampling mode. These floats will provide high temporal and vertical resolutions of co-located ocean velocity, temperature, salinity, turbulence, and acoustic tracking on deep surfaces of constant density. With these new acoustic tracking and surface following capabilities, combined with short vertical excursions around the target density surface, we will be able to address new scientific questions. Vertical stratification, velocity shear, and mixing are essential for most processes operating at the interior submesoscale - turbulence, internal waves, vortex stirring, and critical layers. The slow evolution of unforced interior motion is well-matched to the new sampling capabilities. Potential uses of an array of these floats will be to samplean energetic turbulent layer (e.g. a separated seamount wake) for 1#2 weeks, or the evolution of the core of a water-mass for multiple months. EM-APEX floats have been used in numerous ONR experiments, including CBLAST, QPE, ITOP, OKMC, LatMix, NISKINE, and ARCTERX. These floats have performed very well and provided quality observations. We plan to deploy these ten floats in the upcoming ONR-DRI RIOT field experiments in 2025 and 2026. As a Lagrangian swarm, these floats will sample vertical finescale structure and resolve horizontal gradients and submesoscale structure as the interior ocean evolves under the influence of internal waves, mixing, vortex stirring, critical layers, and small-scale circulation.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 13, 2025
- Source ID
- N000142512052
Entities
People
- Zoltan Szuts
Organizations
- Office of Naval Research
- United States Navy
- University of Washington