The parameter heff can uniquely be determined by (5.4); then the parameter L(θ) is determined by (5.3). Finally, the “integraldepression” (ID) of the thermocline caused by the ISW can be estimated. The ID roughly represent the total energy carried by the ISW packet.
Our numerical result shows that (ID)eff=1.4 105m2, is pretty close to the real value of the depression area, (ID)real = 1.5 105m2
On the other hand, if the real width of the ISW is provided independently by radar or SAR, then only use (5.3) to retrieve the parameter heff can get more robust result.
6. CONCLUDING REMARKS
(1) By using lower frequency, we do have some working space that allows us to do the tomographic inversion based on adiabatic mode theory even for the sever non-gradual ocean dynamic structures such as : fron, ISW. Kuroshio.
(2) Horizontal-refraction-modal tomography has the potential of reducing the mode-coupling impact due to the fact of measuring the subtraction of two close paths, and it turns out that the proposed “iterative” procedure can effectively deal with significant mode coupling case.
(3) The proposed MPT and MHRT offers some potential applications for acoustic remote sensing. Theoretical frame and numerical simulation studies have been performed, and promising results for retrieving mesoscale structures, transvers current, front, andinternal solitary waves have been obtained. We are expecting that some seagoing experiments can be performed in the future by joining both the oceanographic community and the acoustic community.
ACKNOWLEDGMENT
This work was supported by ONR and NOAA. The computer code used in the simulations are provided by Dr. Ding Lee (IFDPE) and Dr.M. Poter (KRAKEN).
