Determination of characteristics of short-period internal waves by the cross-correlation method

The paper proposes an approach for automatic estimation of the parameters of short-period internal waves using a combination of correlation processing and numerical methods. The application of the method of cross-correlation processing to determine the propagation delay of short-period internal waves is considered, and the application of numerical methods to estimate the direction of propagation of short-period internal waves is described. The sensitivity of the cross-correlation processing method to noise was evaluated using simulation modeling, which showed that this method provides an estimate of the propagation delay with an accuracy of at least 10 % for a signal-to-noise ratio of at least 1.75. Two variants of the numerical solution of the problem of determining the direction of propagation of short-period internal waves are described. The approach has been tested by processing in situ data obtained from drifting thermal profiling buoys. The results of estimating the parameters of the velocity and direction of propagation of short-period internal waves obtained by the analytical method, the numerical method and the method of compressible intervals have been compared, which showed their good convergence. It is noted that the described approach is promising for implementation in real-time monitoring systems.

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