Inter-comparison of WAM and WAVEWATCH-III in the North Indian Ocean using ERA-40 and QuikSCAT/NCEP blended winds

In this work we present the inter-comparison of wave hindcasts using third generation models WAM and WAVEWATCH (WWIII) for the North Indian Ocean at a 1° × 1° (lat × long) grid resolutions and we show a first assessment of their relative performance by inter-comparing the model results to observational data at selected points in the Arabian Sea and Bay of Bengal. WAM and WWIII inter-comparison studies are carried out for the year 2000 and for the period June 2008 to June 2009. Overall, the inter-comparison shows that both wave models are rather skillful in predicting the integral wave parameters; with lesser PE of the range 8.9-26.7% using WAM than WWIII. It is also quite evident that the WWIII model has a tendency to overestimate mean wave periods, while the opposite is true for WAM model. Further, the validation results using altimeter measurements are quite promising in the Arabian Sea and Bay of Bengal. The study further suggests that, it would be wise to use long-term measurements both in deep and coastal waters of North Indian Ocean to validate and inter-compare WAM and WWIII further, and they may also be coupled with SWAN for the nearshore waters.