4-D COASTAL OCEAN DYNAMICS DETECTED BY SURFACE CURRENT

RADAR AND AUVsL. K. Shay

Meteorology and Physical Oceanography University of Miami

P. Edgar AnOcean Engineering

Florida Atlantic University

SCIENTIFIC GOAL:

To provide a first-order description of complex oceanic flows and their relationship to surface processes in the littoral ocean subjected to tidal currents, western boundary currents, topographical changes and surface winds.

RESEARCH SUPPORTED BY ONR.

LITTORAL ZONE

Complex Coastal Processes. 2-D/ 3-D Flow Fields. Boundary Current & Topography. Waves & Boundary Layer Winds. Impact: Civilian and US Navy Needs. Radar/AUV/Mooring/Ship-based

Approach. Applicable to Any Theater.

Ocean Explorer AUV

VHF RADAR

Phased Array 32 Elements. Electronic Beam Forming. 700 Cells (250 m resolution). 60 km Square Domain. 20 Minute Sample Cycle. Theoretical Limit 11 km. Spectra and Currents.

ENGINEERINGOBJECTIVES:

Design/Implement Multiple ADCPs as Part of AUV Payload.

Evaluate Side-Looking Beam Orientations.

Map Currents Relate To Surface Dynamics.

Train Next Generation Graduate Students (i.e. Tactical Oceanography)

SCIENCE OBJECTIVES:

Coherent Structures (Vortices, Fronts) Isolate BC and Tidal Flows/Forcing of

Iws At Shelf Break. Expand IWs Into Baroclinic Modes. Determine Wavenumber Spectra. Assess Boundary Layer Processes

During Storm and Quiescent Periods.

Experimental Domain

EXPERIMENTALDESIGN

VHF Mode of OSCR (7x9 km: 250 m Cell Spacing).

Ship-Based CTD/ADCP (2x2 km) 4-AUV Sampling Patterns (0.5-1km). Cyclesonde. NOVA/USF Moorings. NAVY ADCPs.

Experimental Domain

Sub-Mesoscale Vortex

Vortex Propagation

Surface Current Regimes

Strong Florida Current Lobe Structure

AUV MISSIONS

Mixed Layer: (Current and Turbulence)

Tidal Current: Bottom Boundary: Turbulence: Planned Adverse

Weather:

6 and 12-hr repeated grids : 500 m x 500 m.

15-26 hr: 1km x 1km 7 hr: 1 km x .500 km 4-6 hr: 1 km Xsects 12 hr : 500 m x 500

m (March-April 00)

AUV Section

AUV Maps

Ship ADCP Transect

Ship ADCP/AUV and OSCR Comparison

Mooring Comparison

FUTURE RESEARCH

Long-Term Monitoring of Florida Current Using HiFAR (100 km range).

Develop Long-Range AUVs (24-48 hr). Surface/Subsurface Moorings (Cross-

Shelf) Ship-Based Observations (Cross-Shelf) Drifter-Based Deployments Modeling/Assimilation

GOAL:

To assess long-term variability of the Florida Current and its influence on Coastal Circulation and Atmospheric Weather Patterns/Events.

Important to Civilian Needs (Ship Traffic; Pollutant Dispersion; Renourishment.)

Important to Navy (Ship/Radar Signatures; Acoustics;Internal Waves)

SFTF APPLICATIONS

US Navy Coastal Surveys. METOC (JTFX) Operations. Ship-based Operations In Differing

Venues/Theaters. Coupling With Models (i.e. LES). Provides Environmental Data To

Assess Impact on Fleet Operations.

SUMMARY

Synergistic Approach: Synoptic Variability.

Fine-Scale to Submesoscale Processes. 2-D/3-D Variability not Mean. Real Time: JTFX (Ships,Aircraft,AUV). Improve Predictive Capability At Navy

Centers. Train Next-Generation Students.