The lack of adequate observational information over the ocean, create a great difficulty in prediction of ocean state near
the Indian coasts. Frequent satellite passes over this region provides valuable wind data resources that can be used to
force regional models to evaluate ocean wave spectrum near coasts with a better accuracy. In this work both
scatterometer wind from QuikSCAT as well as the ETA model wind from NCMRWF are used to force coastal wave
model SWAN nested in open-ocean WAM model. The results indicate that the SWAN nested in WAM predicts the wind
generated wave height with better accuracy when forced when forced with the QuikSCAT wind. But the swell height
predominantly depends on the boundary conditions provided on the model.
In the present study, experiments have been performed to observe the impact of Southern Ocean Swell in the Indian
Ocean region. For this purpose, wave model (WAM) runs have been made for two years using National Centre for
Medium Range Weather Forecasting model derived analysed winds and QuikScat scatterometer derived surface winds.
To observe the swell impact in Indian Ocean region, the wave models runs have been made in global as well as regional
scale. The difference in the model derived wave heights have been compared with in-situ buoy data as well as satellite
altimeter derived wave height data. The study clearly demonstrates that high swell waves from the Southern Ocean
propagate towards the Bay of Bengal and Arabian Sea.
A comparative study of ENVISAT ASAR data and corresponding wave rider buoy data has been attempted. An
algorithm has been developed to retrieve Ocean Wave Spectrum from SAR data. The resulting spectrum is compared
with the wave rider buoy measured wave spectrum. To compute the 2-D image spectrum from multi-look SAR data,
various corrections to the original SAR data has been applied. Thereafter, Modulation Transfer Function has been
computed and utilized to convert image spectrum to the Ocean Wave Spectrum. This final ocean wave height spectrum
is used to estimate the ocean wave spectral parameters and has been compared with the in-situ measurements and model
derived wave spectrum. An attempt has also been made to process the Single Look Complex (SLC) data to reduce the
speckle noise in the SAR data using Fast Fourier Transform (FFT).