Inter-comparisons of SWAN hindcasts using boundary conditions from WAM and WWIII for northwest and northeast coasts of India

In this study, we present the inter-comparison of regional SWAN hindcasts using boundary conditions (BC) from the third generation wave models WAM and WWIII implemented globally. Here, SWAN inter-comparison studies with outputs of both global models as well as SWAN results using BC from both WAM and WWIII were carried out for selected months of the year 2000, 2008, 2009 and for the full year 2011 using ERA-40, QuikSCAT/NCEP Blended and OSCAT winds. The results of this experimental simulations/hindcasts suggests that SWAN hindcasts for both the northwest coast as well as northeast coastal model domains in the present model setups were found to be different, and can be considered better than the deep water model outputs such as WAM and WWIII, implemented globally. The comparison between SWAN hindcasts using WAM BC and SWAN hindcasts using WWIII BC revealed high correlations. However, the Percentage Error in the hindcast results of SWAN using WAM BC were found to be generally higher by 5-15% by considering most of the case studies presented in this investigation. Further, the validation results using in-situ and altimeter measurements suggest that SWAN using WAM BC can be an effective means of obtaining more accurate nearshore wave predictions.