In-ocean solitary wave amplitude inversion method, electronic device and readable storage medium

Abstract

The invention provides an in-ocean solitary wave amplitude inversion method, an electronic device and a readable storage medium, SWOT satellite observation data is combined with other remote sensing means observation data of close time to form a double-time-phase remote sensing image, and then the observed in-ocean solitary wave amplitude of a target sea area is obtained. According to the method, large-area two-dimensional sea surface height observation data with high resolution and high precision can be provided based on radar interference measurement, and under the condition that sea surface height abnormity caused by the marine internal solitary waves on the sea surface can be captured, the amplitude of the internal solitary waves is obtained in combination with other remote sensing observation data, so that the calculation process is simplified, and the calculation efficiency is improved. And the inversion precision is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of ocean solitary wave amplitude prediction, and in particular relates to an ocean solitary wave amplitude inversion method, an electronic device and a readable storage medium. Background Art

[0002] Internal ocean waves are a kind of fluctuation phenomenon that occurs in the interior of the stably stratified ocean, with a frequency between the inertial frequency and the buoyancy frequency, and its maximum amplitude occurs in the interior of the ocean. When the density of the seawater is stably stratified and there is a disturbance source, internal waves may be generated. The frequently observed internal ocean waves are a special type called internal solitary waves, which are usually generated by the interaction between the positive pressure tide and the terrain. During the propagation process, the internal tidal waves undergo nonlinear steep slopes, thereby splitting into internal solitary waves.

[0003] In the prediction and inversion technology of internal solitary waves in the ocean, at present, there are many documents published for the prediction of internal wave velocity, such as "Construction and Evaluation of Internal Solitary Wave Velocity-Gaussian Function Model", "Computer Algebra Research on Internal Solitary Waves", "Propagation Evolution Characteristics of Weak Nonlinear Internal Solitary Waves on Slopes" and other papers, as well as patent documents such as CN115859021B and CN118114030B, which all disclose how to obtain the propagation velocity of internal solitary waves through remote sensing means. However, there is relatively no simple solution for the field of remote sensing detection of internal solitary wave amplitude at this stage, and most internal solitary wave amplitude inversion solutions have the defects of poor accuracy and high error. Summary of the invention

[0004] In order to make up for the above-mentioned technical defects of internal solitary wave amplitude inversion, the present application proposes a method, an electronic device and a readable storage medium for inversion of ocean internal solitary wave amplitude, which can provide high-resolution and high-precision large-area two-dimensional sea surface height observation data based on radar interferometry. When the sea surface height anomaly caused by the ocean internal solitary wave on the sea surface can be captured, the internal solitary wave amplitude data can be obtained in combination with other remote sensing observation data, thereby simplifying the calculation process and improving the inversion accuracy.

[0005] The method and technical scheme include: a method for inverting the amplitude of internal solitary waves in the ocean, characterized in that the SWOT satellite observation data is combined with other remote sensing means observation data of the nearby time to form a dual-phase remote sensing image, and then the amplitude of the internal solitary waves observed in the target sea area is obtained.

[0006] The steps include:

[0007] The sea surface height anomaly ζ of the target sea area is obtained based on the internal solitary wave remote sensing image observed by the SWOT satellite in the target sea area;

[0008] According to the target sea area chart and ocean numerical model data, the water depth data and temperature-salinity profile data of the target sea area are obtained, and the seawater buoyancy frequency number N of the target sea area is calculated;

[0009] Through the water depth data and seawater buoyancy frequency, according to the vertical structure function of the internal solitary wave, the linear phase velocity c0 of the internal solitary wave in the target sea area is obtained;

[0010] Collect other remote sensing images of the target sea area observed by SWOT satellite at the same time to form a dual-phase remote sensing image of the internal solitary wave, and obtain the propagation speed v of the internal solitary wave according to the dual-phase remote sensing image;

[0011] According to the strong nonlinear Miyata–Choi–Camassa (MCC) model under free surface boundary conditions, the relationship between the sea surface height anomaly in the target sea area and the vertical displacement of the interface between the two layers of fluid and the upper and lower fluid data in the two layers of fluid is obtained, and then the vertical displacement data η is obtained by combining the relationship between the internal solitary wave propagation velocity v, the internal solitary wave linear phase velocity c0 and the upper and lower fluid data in the two layers of fluid and the vertical displacement of the interface between the two layers of fluid;

[0012] The amplitude of the observed internal solitary wave in the target sea area is obtained based on the vertical displacement.

[0013] Furthermore, the other remote sensing images include one or more of synthetic aperture radar (SAR) satellite remote sensing images, visible light satellite remote sensing images, shipborne X-band radar remote sensing images and aerial remote sensing images.

[0014] Furthermore, the step of obtaining the seawater buoyancy frequency N includes:

[0015]

[0016] Among them, ρ is the density of seawater, z is the water depth, and g is the acceleration due to gravity.

[0017] Furthermore, the linear phase velocity c0 of the internal solitary wave propagation is calculated by the internal solitary wave vertical structure function Obtain, among which is the eigenfunction of the first mode of the internal solitary wave.

[0018] Furthermore, the step of obtaining the vertical displacement η of the interface between the two layers of fluid comprises:

[0019] Obtain the relationship between the sea surface height anomaly ζ in the target sea area and the vertical displacement η of the interface between the two layers of fluid and the upper and lower fluid data in the two layers of fluid, referred to as the vertical displacement relationship:

[0020]

[0021] Obtain the relationship between the internal solitary wave propagation velocity v, the internal solitary wave linear phase velocity c0 and the vertical displacement η of the interface between the two layers of fluid and the upper and lower fluid data in the two layers of fluid, referred to as the propagation velocity relationship:

[0022]

[0023] Obtain the relationship between the internal solitary wave linear phase velocity c0 and the upper and lower fluid data in the two-layer fluid, referred to as the linear phase velocity relationship:

[0024]

[0025] According to the vertical displacement relationship, propagation velocity relationship and linear phase velocity relationship, the vertical displacement η of the interface between the two layers of fluid is obtained by jointly solving the three relationships.

[0026] Among them, Δ is the density difference between the upper and lower fluids of the two layers of fluid, and its value is H is the total water depth of the target sea area, H=h1+h2, ρ1 and h1 are the density and thickness of the upper fluid in the two-layer fluid system, ρ2 and h2 are the density and thickness of the lower fluid, and g is the gravitational acceleration.

[0027] Furthermore, the proximity time is an interval value greater than 0 and not greater than the internal solitary wave generation period of the sea area.

[0028] Furthermore, the process of obtaining the amplitude of the internal solitary wave observed in the target sea area according to the vertical displacement of the inner interface between the two layers of fluid includes taking the absolute value η0 of the vertical displacement η of the inner interface between the two layers of fluid as the amplitude of the internal solitary wave observed in the target sea area.

[0029] The present application also proposes an electronic device, which includes a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of any of the methods described above are implemented.

[0030] The present application also proposes a readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, the steps of any of the methods described above are implemented.

[0031] Compared with the traditional internal solitary wave amplitude remote sensing inversion method, this application avoids the internal solitary wave amplitude inversion error introduced by the calculation error of the upper layer thickness h1 and the density difference Δ in the traditional internal solitary wave amplitude remote sensing inversion process, and improves the accuracy of satellite ocean internal solitary wave amplitude inversion. It makes full use of the sea surface height anomaly of the ocean internal solitary wave observed by the SWOT satellite, which is more accurate than the bright and dark alternating stripe feature information observed from SAR, visible light or shipborne X-band radar remote sensing images, avoids the amplitude inversion error introduced by the error of extracting the bright and dark alternating stripe feature information, and improves the accuracy of satellite ocean internal solitary wave amplitude inversion. It is only necessary to directly obtain the sea surface height anomaly and the internal solitary wave propagation speed respectively through the dual-phase remote sensing image based on the SWOT satellite, directly obtain the total water depth through the nautical chart, and solve the internal solitary wave linear phase velocity, and then the remotely sensed ocean internal solitary wave amplitude can be obtained by jointly solving multiple relationship equations, simplifying the satellite ocean internal solitary wave amplitude inversion technology The dependence on the ocean internal wave dynamic process. By collecting remote sensing data such as SAR, visible light or ship-borne X-band radar, we can form dual-phase remote sensing images based on SWOT satellites. By utilizing the advantages of dual-phase remote sensing images, we can not only obtain more accurate propagation speeds of ocean internal solitary waves and improve the accuracy of satellite ocean internal solitary wave amplitude inversion, but also give full play to the advantages of multi-source and multi-phase remote sensing images of ocean internal solitary waves. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 The present invention is a schematic flow chart of an embodiment of the method of the present invention. DETAILED DESCRIPTION

[0034] The technical solution of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0035] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0036] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0037] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0038] Combination Figure 1 , an implementation mode of the present application.

[0039] A method for inverting the amplitude of an internal solitary wave in the ocean is provided. The method forms a dual-phase remote sensing image by combining SWOT satellite observation data with observation data of other remote sensing means in the near time, and then obtains the amplitude of the internal solitary wave observed in the target sea area. The method comprises the following steps: obtaining the sea surface height anomaly ζ of the target sea area according to the internal solitary wave remote sensing image data observed by the SWOT satellite in the target sea area; obtaining the water depth data and temperature-salinity profile data of the target sea area according to the nautical chart of the target sea area and the ocean numerical model data, and calculating the seawater buoyancy frequency number N of the target sea area; solving and obtaining the linear phase velocity c0 of the internal solitary wave in the target sea area according to the water depth data and the seawater buoyancy frequency and the vertical structure function of the internal solitary wave; collecting the SWOT data of the target sea area; obtaining the internal solitary wave linear phase velocity c0 ... The satellite observes other remote sensing images of the adjacent time to form a dual-phase remote sensing image of the internal solitary wave, and the internal solitary wave propagation velocity v is obtained according to the dual-phase remote sensing image; according to the strong nonlinear Miyata-Choi-Camassa (MCC) model under the free surface boundary condition, the relationship between the sea surface height anomaly in the target sea area and the vertical displacement of the internal interface of the two-layer fluid and the upper and lower fluid data in the two-layer fluid is obtained, and then the relationship between the internal solitary wave propagation velocity v, the internal solitary wave linear phase velocity c0 and the upper and lower fluid data in the two-layer fluid and the vertical displacement of the internal interface of the two-layer fluid is combined to obtain the vertical displacement data η through the above relationship; the amplitude of the internal solitary wave observed in the target sea area is obtained according to the vertical displacement. In this embodiment, when the internal solitary wave of the ocean exists, the sea surface height and the sea surface roughness will change. Compared with the traditional altimeter, the SWOT (Surface Water and Ocean Topography) satellite can provide high-resolution and high-precision large-area two-dimensional sea surface height observation data through radar interferometry, so that the sea surface height anomaly caused by the internal solitary wave of the ocean on the sea surface can be captured. At the same time, due to the strong nonlinear characteristics of the internal solitary wave, the phenomenon of convergence and divergence occurs on the sea surface, causing changes in the roughness of the sea surface, thereby presenting bright and dark stripe characteristics on the SAR, visible light or shipborne X-band radar remote sensing images. Based on the remote sensing image of the internal solitary wave in the ocean observed by the SWOT satellite in a certain sea area, combined with the SAR or, visible light or shipborne X-band radar remote sensing image of the internal solitary wave in the ocean observed by the SWOT satellite at the same observation sea area (the adjacent time interval value is greater than 0 and not greater than the internal solitary wave generation period of the sea area, and the smaller the adjacent time interval value is, the better) in the same observation sea area, the propagation velocity v of the internal solitary wave in the ocean can be calculated. On the basis of the above embodiment, further, the other remote sensing images include one or more of SAR remote sensing images, visible light satellite remote sensing images, shipborne X-band radar images and aerial remote sensing images.The satellites at different times of the dual-phase remote sensing images composed of the SWOT satellite are usually satellite remote sensing data such as SAR or visible light. They can also be ocean internal solitary wave remote sensing images obtained by other means such as shipborne X-band radar and aerial remote sensing. They are not necessarily required to be satellite remote sensing images.

[0040] Based on one or more of the above embodiments, further, the step of acquiring the seawater buoyancy frequency N includes:

[0041]

[0042] Among them, ρ is the density of seawater, z is the water depth at that location, and g is the acceleration due to gravity.

[0043] Based on one or more of the above embodiments, further, the internal solitary wave propagation linear phase velocity c0 is calculated by the internal solitary wave vertical structure function Obtain, among which is the eigenfunction of the first mode of the internal solitary wave.

[0044] Based on one or more of the above embodiments, further, the step of obtaining the vertical displacement η of the inner interface of the two layers of fluid comprises:

[0045] Obtain the relationship between the sea surface height anomaly ζ in the target sea area and the vertical displacement η of the interface between the two layers of fluid and the upper and lower fluid data in the two layers of fluid, referred to as the vertical displacement relationship:

[0046]

[0047] Obtain the relationship between the internal solitary wave propagation velocity v, the internal solitary wave linear phase velocity c0 and the vertical displacement η of the interface between the two layers of fluid and the upper and lower fluid data in the two layers of fluid, referred to as the propagation velocity relationship:

[0048]

[0049] Obtain the relationship between the internal solitary wave linear phase velocity c0 and the upper and lower fluid data in the two-layer fluid, referred to as the linear phase velocity relationship:

[0050]

[0051] According to the above three relationship equations of vertical displacement relationship, propagation velocity relationship and linear phase velocity relationship, the vertical displacement η of the inner interface of the two layers of fluid is obtained by jointly solving the above three relationship equations;

[0052] Among them, Δ is the density difference between the upper and lower fluids of the two layers of fluid, and its value is H is the total water depth of the target sea area, H=h1+h2, ρ1 and h1 are the density and thickness of the upper fluid in the two-layer fluid system, ρ2 and h2 are the density and thickness of the lower fluid, and g is the gravitational acceleration.

[0053] In this embodiment, according to the strong nonlinear Miyata–Choi–Camassa (MCC) model under free surface boundary conditions, the sea surface height anomaly ζ and the vertical displacement η of the interface between the two layers of fluid and the upper and lower fluid data in the two layers of fluid exist in the following relationship: Wherein, ζ is the sea surface height anomaly of the ocean internal solitary wave observed by the SWOT satellite; η is the vertical displacement of the interface between the two layers of fluid, and its absolute value is the ocean internal solitary wave amplitude η0 observed by the SWOT satellite; when the ocean internal solitary wave is a descending internal solitary wave, ζ>0, η<0; when the ocean internal solitary wave is an ascending internal solitary wave, ζ<0, η>0.

[0054]

[0055]

[0056] H=h1+h2

[0057] c0 is the linear phase velocity of the internal solitary wave, which can be obtained from the vertical structure function of the internal solitary wave get

[0058] In the formula, is the eigenfunction of the first mode of internal solitary wave, N is the buoyancy frequency of seawater, ρ is the seawater density, z is the water depth, and the seawater density can be obtained through the temperature-salinity profile data of the SWOT satellite observation area and observation period provided by the ocean numerical model. In the above three relationships of vertical displacement relationship, propagation velocity relationship and linear phase velocity relationship, there are 7 variables. Among them, the vertical displacement η of the interface between the two layers of fluid, the density difference Δ and the upper layer thickness h1 are 3 unknown variables; the sea surface height anomaly ζ, seawater depth H, internal solitary wave linear phase velocity c0 and internal solitary wave propagation velocity v of the ocean are 4 known variables. At this time, the three unknown quantities just correspond to the three relationships of vertical displacement relationship, propagation velocity relationship and linear phase velocity relationship. Therefore, the vertical displacement η of the interface between the two layers of fluid, the density difference Δ and the upper layer thickness h1 can be obtained by joint solution. Taking the absolute value η0 of the vertical displacement η of the interface between the two layers of fluid, the amplitude η0 of the ocean solitary wave observed by the SWOT satellite can be obtained.

[0059] Based on one or more of the above embodiments, further, the proximity time is an interval value greater than 0 and not greater than an internal solitary wave generation period of the sea area.

[0060] Based on one or more of the above embodiments, further, the process of obtaining the amplitude of the internal solitary wave observed in the target sea area according to the vertical displacement includes taking the absolute value η0 of the vertical displacement η of the inner interface of the two layers of fluid as the amplitude data of the internal solitary wave observed in the target sea area.

[0061] The present invention also proposes an electronic device, which includes a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the method described in any of the above embodiments are implemented.

[0062] The present invention further proposes a readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, the steps of the method described in any of the above embodiments are implemented.

[0063] Compared with the traditional internal solitary wave amplitude remote sensing inversion method, this application avoids the internal solitary wave amplitude inversion error introduced by the calculation error of the upper layer thickness h1 and the density difference Δ in the traditional internal solitary wave amplitude remote sensing inversion process, and improves the accuracy of satellite ocean internal solitary wave amplitude inversion. It makes full use of the sea surface height anomaly of the ocean internal solitary wave observed by the SWOT satellite, which is more accurate than the bright and dark alternating stripe feature information observed from SAR, visible light or shipborne X-band radar remote sensing images, avoids the amplitude inversion error introduced by the error of extracting the bright and dark alternating stripe feature information, and improves the accuracy of satellite ocean internal solitary wave amplitude inversion. It is only necessary to directly obtain the sea surface height anomaly and the internal solitary wave propagation speed respectively through the dual-phase remote sensing images based on the SWOT satellite, directly obtain the total water depth through the nautical chart, and obtain the linear phase velocity by solving the vertical structure function of the internal solitary wave, and then calculate the ocean internal solitary wave amplitude observed by remote sensing, which simplifies the dependence of the satellite ocean internal solitary wave amplitude inversion technology on the ocean internal wave dynamic process. By collecting remote sensing data such as SAR, visible light or ship-borne X-band radar, we can form dual-phase remote sensing images based on SWOT satellites. By utilizing the advantages of dual-phase remote sensing images, we can not only obtain more accurate propagation speeds of ocean internal solitary waves and improve the accuracy of satellite ocean internal solitary wave amplitude inversion, but also give full play to the advantages of multi-source and multi-phase remote sensing images of ocean internal solitary waves.

[0064] The above technical solutions only reflect the preferred technical solutions of the technical solutions of the present invention. Some changes that may be made to certain parts thereof by technicians in this technical field all reflect the principles of the present invention and fall within the protection scope of the present invention.

Claims

1. A method for inverting the amplitude of an internal solitary wave in the ocean, characterized in that: The SWOT satellite observation data is combined with other remote sensing observation data of the same time to form a dual-phase remote sensing image, and then the amplitude of the internal solitary wave observed in the target sea area is obtained. The steps include: The sea surface height anomaly ζ of the target sea area is obtained based on the internal solitary wave remote sensing image observed by the SWOT satellite in the target sea area; According to the target sea area chart and ocean numerical model data, the water depth data and temperature-salinity profile data of the target sea area are obtained, and the seawater buoyancy frequency number N of the target sea area is calculated; Through the water depth data and seawater buoyancy frequency, according to the vertical structure function of the internal solitary wave, the linear phase velocity c0 of the internal solitary wave in the target sea area is obtained; Collect other remote sensing images of the target sea area observed by SWOT satellite at the same time to form a dual-phase remote sensing image of the internal solitary wave, and obtain the propagation speed v of the internal solitary wave according to the dual-phase remote sensing image; According to the strong nonlinear Miyata–Choi–Camassa (MCC) model under free surface boundary conditions, the relationship between the sea surface height anomaly in the target sea area and the vertical displacement of the interface between the two layers of fluid and the upper and lower fluid data in the two layers of fluid is obtained, and then the vertical displacement data η is obtained by combining the relationship between the internal solitary wave propagation velocity v, the internal solitary wave linear phase velocity c0 and the upper and lower fluid data in the two layers of fluid and the vertical displacement of the interface between the two layers of fluid; The amplitude of the observed internal solitary wave in the target sea area is obtained based on the vertical displacement.

2. The method according to claim 1, characterized in that The other remote sensing images include one or more of synthetic aperture radar (SAR) satellite remote sensing images, visible light satellite remote sensing images, shipborne X-band radar remote sensing images and aerial remote sensing images.

3. The method according to claim 1, characterized in that The step of obtaining the seawater buoyancy frequency N comprises: Among them, ρ is the density of seawater, z is the water depth, and g is the acceleration due to gravity.

4. The method according to claim 3, characterized in that The linear phase velocity c0 of the internal solitary wave propagation is calculated by the internal solitary wave vertical structure function Obtain, among which is the eigenfunction of the first mode of the internal solitary wave.

5. The method according to claim 4, characterized in that The step of obtaining the vertical displacement η of the interface between the two layers of fluid comprises: Obtain the relationship between the sea surface height anomaly ζ in the target sea area and the vertical displacement η of the interface between the two layers of fluid and the upper and lower fluid data in the two layers of fluid, referred to as the vertical displacement relationship: Obtain the relationship between the internal solitary wave propagation velocity v, the internal solitary wave linear phase velocity c0 and the vertical displacement η of the interface between the two layers of fluid and the upper and lower fluid data in the two layers of fluid, referred to as the propagation velocity relationship: Obtain the relationship between the internal solitary wave linear phase velocity c0 and the upper and lower fluid data in the two-layer fluid, referred to as the linear phase velocity relationship: According to the vertical displacement relationship, propagation velocity relationship and linear phase velocity relationship, the vertical displacement η of the interface between the two layers of fluid is obtained by jointly solving the three relationships. Among them, Δ is the density difference between the upper and lower fluids of the two layers of fluid, and its value is H is the total water depth of the target sea area, H=h1+h2, ρ1 and h1 are the density and thickness of the upper fluid in the two-layer fluid system, ρ2 and h2 are the density and thickness of the lower fluid, and g is the gravitational acceleration.

6. The method according to claim 1, characterized in that The approach time is an interval value greater than 0 and not greater than the internal solitary wave generation period of the sea area.

7. The method according to claim 5, characterized in that The process of obtaining the amplitude of the internal solitary wave observed in the target sea area according to the vertical displacement of the inner interface of the two layers of fluid includes taking the absolute value η0 of the vertical displacement η of the inner interface of the two layers of fluid as the amplitude of the internal solitary wave observed in the target sea area.

8. An electronic device, characterized in that: The electronic device includes a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the method according to any one of claims 1 to 7 are implemented.

9. A readable storage medium, characterized in that: The readable storage medium stores a program or an instruction, and when the program or the instruction is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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