Accession Number:

ADA379451

Title:

Frontal Instabilities in a Buoyant Plume

Descriptive Note:

Conference proceedings

Corporate Author:

NAVAL RESEARCH LAB STENNIS SPACE CENTER MS COUPLED DYNAMIC PROCESSES SECTION

Personal Author(s):

• Gallacher, Patrick C.
• Schaferkotter, Michael
• Martin, Paul J.

Report Date:

1998-12-05

Pagination or Media Count:

8.0

Abstract:

Many phenomena in the coastal ocean produce surface signatures that appear in remotely sensed images. We are interested in understanding the dynamics that control these phenomena, particularly those seen in Synthetic Aperture RADAR SAR images. Some of the signatures in SAR images are associated with convergence fronts produced by buoyant plumes. Fresh water discharges from rivers and bays into the saltier shelf water can form such plumes. The plumes and the associated fronts can extend for hundreds to thousands of meters and have widths of meters to tens of meters. The plumes can propagate tens to a hundred of kilometers from their source. We used three models to simulate buoyant jets a 2.D nonhydrostatic channel model, a 3-D nonhydrostatic Large Eddy Simulation LES model and a 3-D hydrostatic model. The hydrostatic model is the Navy Coastal Ocean Model NCOM which is a component of the Coupled Ocean Atmosphere Prediction System COAMPS. The LES model separates the flow by physical scales rather into mean and turbulent components. The nonhydrostatic models simulated the Lock Exchange problem using idealized geometries at relatively small scales. The hydrostatic models simulates the Chesapeake Bay outflow plume using realistic topography and geometry.

Descriptors:

• *OCEAN MODELS
• COMPUTERIZED SIMULATION
• SYNTHETIC APERTURE RADAR
• RADAR IMAGES
• HYDROSTATICS
• PLUMES
• CHESAPEAKE BAY

Subject Categories:

• Meteorology
• Physical and Dynamic Oceanography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE