A previously calibrated numerical three-dimensional hydrodynamic model for Los Angeles-Long Beach Harbors, California, was applied to study the combined effects of tide and wind on circulation. The model was calibrated and verified successfully with field data for a summer wind condition. In this report the calibration is compared to a no-wind condition to understand the effects of typical wind conditions on circulation. Also, wind conditions for approaching (winds from the southeast) and passing (winds from the north) frontal systems, typical of fall-winter weather patterns, were simulated. Results indicated the effects of wind can be significant. Harbors, Long Beach Harbor, Wind-driven circulation. Hydrodynamics, Numerical models, Los Angeles Harbor, Tidal circulation.

A previously calibrated numerical three-dimensional hydrodynamic model for Los Angeles-Long Beach Harbors, California, was applied to study the combined effects of tide and wind on circulation. The model was calibrated and verified successfully with field data for a summer wind condition. In this report the calibration is compared to a no-wind condition to understand the effects of typical wind conditions on circulation. Also, wind conditions for approaching (winds from the southeast) and passing (winds from the north) frontal systems, typical of fall-winter weather patterns, were simulated. Results indicated the effects of wind can be significant. Harbors, Long Beach Harbor, Wind-driven circulation. Hydrodynamics, Numerical models, Los Angeles Harbor, Tidal circulation.

To meet future needs, the Ports of Los Angeles and Long Beach have undertaken a long-range cooperative planning effort known as the 2020 Plan. Under this master plan, a number of phased plans have been determined to accommodate future needs. These plans involve deepening of ship channels and harbors and creation of new landfills. The purpose of the study described in this report was to determine three-dimensional hydrodynamics of tidal and wind- driven circulation for existing conditions as well as a plan condition selected by the ports. This goal was accomplished by applying a state-of-the-art, 3-D numerical hydrodynamic model called GH3D. The model results also were used to drive a separate water quality model. In order to calibrate and verify the GH3D model, comprehensive field data were collected in the summer of 1987. These included surface elevation data measured at eight locations, current measurements with in situ current meters deployed at nine stations, current velocity profile measurements taken at major entrances to the harbors and interior channels, and a drogue study. The purpose of the study described in this report is to determine three-dimensional hydrodynamics of tidal and wind- driven circulation for the existing harbors and to demonstrate model use in investigating a Phase 1 configuration of a plan determined by the OFI study and selected by the ports.

A tidal circulation study of the Los Angeles and Long Beach Harbors was conducted by the US Army Engineer Waterways Experiment Station. Field data were collected from 5 tide gages and 16 current meters for use in calibration and verification of a numerical circulation model. The methods and results of the field data collection effort are presented. Analysis was performed to verify the quality of the tidal data and the flow patterns revealed by the current data. Keywords: Flowmeters; California; Oceanographic data; Sea water flow; Long Beach Harbor; Los Angeles Harbor; Tidal datum; Ocean tides. (edc).