Development of a Real Time Wave Model for Galveston Bay

Date

2003

Authors

Schmalz RA

Journal Title

Journal ISSN

Volume Title

Publisher

American Society of Civil Engineers

Abstract

The National Oceanic and Atmospheric Administration installed a Physical Oceanographic Real Time System (PORTS) to provide water surface elevation, currents at National Ocean Service prediction depth ( [similar to] 4.6m below MLLW) as well as near-surface and near-bottom temperature and salinity, and meteorological information at six-minute intervals. To complement the PORTS, a nowcast/forecast system has been developed for Galveston Bay using a modified version of the Blumberg-Mellor (1987) three-dimensional circulation model and a one-way coupled fine resolution Houston Ship Channel model (Schmalz, 1998). Daily 24-hour nowcasts and 36-hour forecasts are performed using both bay and channel models in a pseudo-operational setting. This paper investigates the incorporation of a real time wave model component within the present system. Initial test results for two parametric USAGE wave models (CW-167, 1955; CETN-I-6, 1981) as well as for the finite difference-based Donelan (1977) wave model are presented. These tests were performed using constant wind speed and direction to study the behavior of wave growth in each of the models. Next a period in January 1997 was used to evaluate/modify and calibrate the models. A swell open boundary condition was added to the parametric models. For the deep-water Donelan wave model, swell effects were not included, but rather a depth dependent wind to wave momentum transfer coefficient was used to incorporate shallow water effects. Based on these studies a combined parametric model (CETN-I-6 (1981) for significant wave height prediction and CW-167 (1955) for significant wave period prescription) is advanced for incorporation within the present nowcast/forecast system. Finally, data requirements and plans for incorporation of the combined parametric wave model as a subroutine within the circulation model program are discussed

Description

605-614

Keywords

Boundary conditions, Electromagnetic wave diffraction, Electromagnetic wave refraction, Mathematical models, Oceanography, Real time systems, Saline water, Three dimensional, Water, Water resources, Water waves, Weather forecasting, Wind

Citation