Patent ID: 8000945

Claim:
A computer-implemented method for determining characteristics of an underwater bottom roughness field using a numerical wave model, comprising: receiving data of a plurality of wave height measurements for an area of interest, the area of interest comprising a first grid divided into n cells along a first axis and m cells along a second axis normal to the first axis, each node in the first grid being designated by coordinates (i, j), each of the plurality of wave height measurements being associated with one node (i o , j o ) in the first grid; receiving data of a baseline bottom roughness parameter for the area of interest; calculating, using a pre-selected computer, an Influence Matrix based on the baseline bottom roughness parameter; executing, on the pre-selected computer, the numerical wave model selected using an estimated bottom roughness parameter to find a predicted wavefield, the predicted wavefield comprising a plurality of predicted waves having an associated predicted wave height at each node (i o , j o ) in the first grid; calculating, on the pre-selected computer, a difference between a measured wave height and a predicted wave height at each node (i o , j o ) in the first grid to obtain a maximum wave height error, the maximum wave height error comprising a maximum difference between a predicted wave height and a measured wave height in the area of interest; comparing, on the pre-selected computer, the maximum wave height error to a predetermined minimum tolerance level; and applying, on the pre-selected computer, the Influence Matrix to the estimated bottom roughness parameter to obtain a revised estimated bottom roughness parameter if the maximum wave height error is above the predetermined minimum tolerance level.