Numerical Simulation and Validation of Deepwater Spectral Wind-Waves

Abstract

A numerical simulation study is carried out over Indian Ocean using spectral wind-wave model “WAM.” The surface wind analysis data utilized in this study are generated by assimilation of satellite data in numerical weather prediction models. These winds are used for forcing the ocean WAve Model (WAM) and various spectral and significant wave parameters are simulated. The model simulated outputs viz. significant wave height, peak, and mean wave periods; mean wave and wind-wave directions; the swell wave height, frequency, and direction; frictional wind velocity, wave-induced stress, frequency spectrum, and the two-dimensional directional wave spectrum are presented. A detail analysis is performed to these parameters for assessing spatio-temporal variability for rough weather period (July 1–August 24, 1999). Further, the input wind and simulated waves are validated against ocean buoy observations. The time series spectral evolution of wind-wave in central Bay of Bengal is discussed. The comparison results of significant and spectral wave parameters with measured data co-locating in time and space are presented. The result reveals that the performance of third generation wave model is promising over Indian Ocean despite several limitations. Further, the coincidence and departure of simulated and observed waves are critically examined.

Keywords:

• Oceansat-I
• WAM validation
• analyzed winds
• wave spectrum

Acknowledgements

This work is a part of the PhD dissertation of Dr. J. K. Panigrahi under the faculty of Marine Science, Berhampur University, India. The authors are thankful to the Director, Naval Physical and Oceanographic Laboratory, and Director, Space Application Center, for the encouragement and support provided to carry out this work. We thank Director, National Institute of Ocean Technology, Chennai, for providing the DS3 buoy data for the BOBMEX period. We express sincere thanks to the Director, National Center for Medium Range Weather Forecasting, for providing MSMR analyzed wind field. The corresponding author is recently positioned as Senior Scientist (7) at HR Walling ford and can be reached at [email protected].