Abstract: A method is disclosed to suppress coherent noise in seismic data. Based on the Karhunen-Loeve Transform, this method trains on a region containing undesired coherent noise. Eigenvectors determined from the convariance matrix of that noise are used to reconstruct the noise throughout the data set. Subtracting the reconstruction from the original data leaves a residual in which the coherent noise has been suppressed. Applying this method to a shot record of marine seismic data illustrates that the procedure does suppress noise on actual seismic data.