Estimation of sonic layer depth from surface parameters

Mixed layer depth (MLD) is an important oceanographic parameter. However, the lack of direct observations of MLD hampers both specification and investigation of its spatial and temporal variability. An important alternative to direct observation would be the ability to estimate MLD from surface parameters easily available from satellites. In this study, we demonstrate estimation of MLD using Artificial Neural Network methods and surface meteorology from a surface mooring in the Arabian Sea. The estimated MLD had a root mean square error of 7.36 m and a coefficient of determination (R 2 ) of 0.94. About 67% (91%) of the estimates lie within 5m( 10 m) of the MLD determined from temperature sensors on the mooring.

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