Effects of wave fluctuation on sound propagation

We had performed two experiments in South China Sea(SCS) in 2004 and 2005 under the same environments except a small difference of hydrological condition,but the Transmission Loss(TL) in the two experiments differs greatly.The analysis shows that the difference was caused by fluctuation of the waves.The TL in the experiment of 2005 can be well explained by making use of the absorption coefficients of sea-bottom,inverted from the experiment of 2004 taking the fluctuation of the wave into account.Therefore,we should take the influence of the fluctuation of sea wave into account when doing research on the regulations of underwater sound propagation and the inversions of the geoacoustics parameters.