Study On Extraction And Modeling Of Marine Dynamic Parameters Based On Remote Sensing Data Of Specific Sea Area

The acquisition of Marine information is an important way to understand and use the ocean.With the continuous advancement of the strategy of "maritime power",the research on Marine information monitoring in China is also increasing.High frequency ground wave radar can monitor large area sea condition in real time and is widely used in ocean current monitoring.The ocean current field consists of surface current and deep current,and the extraction of two-dimensional surface current by high-frequency radar has been studied by predecessors.Due to the rapid attenuation of electromagnetic wave in water,the information of deep ocean current cannot be detected directly,and the problem of how to obtain the information of deep ocean current based on radar data is still in the research and exploration stage.On the basis of previous studies,this paper will further study how to obtain two-dimensional and three-dimensional ocean current information from remote sensing information in specific sea areas.The core content of this paper is as follows:1)The ocean current is observed by using the bimodal high-frequency radar.Firstly,the range Doppler spectrum of the radar echo is obtained,and then the effective frequency points in the first-order spectral region are collected.Then,the radial flow field in the ocean surface is obtained by combining the arrival Angle estimation algorithm.The radial flow field obtained by two radar stations was synthesized by vector to obtain a complete two-dimensional flow field.Finally,the resultant results are compared with the measured values of the fixed-point flow measuring equipment to verify the accuracy of the flow field,which provides a reasonable precondition for the inversion of the deep flow field..2)According to the law of ocean kinematics,the basic governing equations of ocean were introduced through the basic principle of dynamics,and then a three-dimensional water model was established for the observed sea area.The original equations were discretised in the model grid by combining with the finite difference algorithm.Then,the two-dimensional flow field was substituted into the three-dimensional mesh model to obtain the deep flow field information by inversion,and the feasibility was preliminarily analyzed through the results.3)according to the characteristics of sea water in improving precision of inversion results and guarantee under the premise of not increase the computational complexity,propose a layering method suitable for sea water grid,originally fixed on the vertical layered approach to dynamic hierarchical,finally will be two kinds of model inversion results compared with the measured values,and to validate the applicability of the optimization model.