Underwater Acoustics and Ocean Dynamics pp 27-35 | Cite as
Acoustic Data Assimilation: Concepts and Examples
Abstract
The ocean is a complicated hydro-dynamic system, showing various interdisciplinary processes of multiple interactive scales. Such processes as internal waves, eddies, and fronts make the ocean acoustic environment drastic changes in time and space. Understanding and modeling physical-acoustical processes are essential for ocean acoustic applications as well as ocean field prediction and parameter estimation. The acoustic data assimilation (ADA), which melds instant observed data of different natures and various physical models, has recently been developed as a new technique for forecasting both ocean and acoustic fields. The general framework of ADA includes three major parts: (1) an observational network for data measurements; (2) a suite of interdisciplinary ocean physics models and the sound propagation model; and (3) data assimilation schemes. Hence it is expected to provide ocean acoustic predictions with higher resolution and better accuracy, compared to those only using the observation data or the physics model. In this paper, we discuss the concepts and framework required to develop the coupled physics-acoustical data assimilation schemes, and review some typical ADA systems and their filed-testing results. It is shown that both the theory and related experiments are advancing steadily.
Keywords
Acoustic data assimilation Ocean acoustic predictions Parameter estimation Physical-acoustical processesNotes
Acknowledgments
This work was supported by the National High Technology Research and Development Program of China (grant No. 2012AA090901), the Fundamental Research Funds for the Central Universities (grant Nos. 2011XZZX003 and 2013XZZX011), and the National Natural Science Foundation of China (grant No. 61171147). The authors want to thank all the researchers in this area for their outstanding work.
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