A15 ROUGH SEA DEGHOSTING USING WAVE HEIGHTS DERIVED FROM LOW FREQUENCY PRESSURE RECORDINGS – A CASE STUDY Abstract 1 By recording very low frequencies of pressure below 0.5 Hz we are able to estimate the wave heights directly above each hydrophone in the seismic streamer as a function of time. Because of the bandwidth separation this can be done without affecting the simultaneously acquired seismic recordings. These wave height estimates are used to derive deterministic deghosting operators that compensate for the rough sea reflection response. We apply the method to a 2D line acquired in the North Sea using a