CoAuthors

S N Acharyulu P (Andhra University, India)

The Indian coastline has been subjected to several geomorphological changes due to natural processes and manmade activities. There are areas of severe erosion and accretion, which lead to loss of several acres of coastal land and accretion of river mouths/inlet preventing the waste water entering into the sea. The most important factor which governs the coastal erosion is wind waves. Attempts were made to predict the waves in deep and intermediate waters but no attempts are made to obtain waves nearer to the coast as the conventional altimeters provide wave measurements as close as maximum up to 6-10 km only but SARAL being new in its kind having such a high frequency and smaller foot print enables measurements of wave data as close as three km from the coast. Also Higher pulse repetition frequency enables more sampling rate. The Bay of Bengal is influenced by three different conditions during a year. They are Southwest monsoon SW (June to September), Northeast monsoon NE (December to February) and a transition period between these two seasons. The wave data obtained from the conventional altimeters during the calm season are are not reliable because of wave heights are so small that will fall within the accuracy of the instrument and provides better correlation of higher wavelengths. The eight-millimetre wavelength of SARAL enables more accurate measurement of the backscatter coefficient over calm or moderate seas. Hence, SARAL data provides better measurements of wind and wave data as close as 3km away from the coast and thus helps us to measure shallow water wave characteristics.