Ocean vortex identification method, system and medium

Abstract

The present invention provides a method, system, and medium for identifying ocean vortices, belonging to the field of ocean vortex identification. The method comprises the following steps: obtaining flow field data of an ocean to be identified, performing an orthogonal transformation on the sea surface flow field in the flow field data to obtain a vector field after the orthogonal transformation; slidingly traversing the vector field after the orthogonal transformation through a sliding window, and using the point with the minimum absolute value of the sea surface flow velocity within the sliding window as the center point of the ocean vortex to be preliminarily determined; and obtaining a new window within the sliding window with the preliminarily determined center point of the ocean vortex as the center, determining the boundary distance according to the golden section method. When the distance between the boundary of the new window and the original sliding window is greater than a preset distance value, and the number of velocity directions of each sea surface flow field within the new window meets a preset number value, then the new window contains an ocean vortex, and calculating the vortex center of the ocean vortex by the least squares method. The method of the present invention helps to achieve efficient identification of ocean vortices.

Description

Technical Field

[0001] The present invention relates to the field of ocean vortex identification, and in particular to an ocean vortex identification method, system and medium. Background Art

[0002] Ocean eddies are localized, rotating circulation structures that form in the ocean. They are widespread across the global ocean and constitute a crucial component of ocean structure. Mesoscale eddies can span timescales from days to hundreds of days and spatial scales from tens to hundreds of kilometers. They can rotate at speeds of several meters per second, flow at high speeds, and reach vertical depths of thousands of meters. The study of ocean mesoscale eddies is crucial for understanding the dynamics of the ocean environment, the structure and function of marine ecosystems, and the mechanisms of marine climate change.

[0003] In order to identify mesoscale vortices, the existing technology provides a mesoscale vortex identification algorithm based on ocean currents (VG method). This method imposes the following restrictions on the vortex center: the magnitude of the velocity component along the east-west direction of the vortex center decreases as the distance from the center increases, and the numerical signs on both sides are opposite; the magnitude of the velocity component along the north-south direction of the vortex center decreases as the distance from the center increases, and the numerical signs on both sides are opposite; the minimum value in the selected area is defined as the approximate position of the center point; near the approximate vortex center point, the rotation direction of the velocity vector must be consistent, that is, the directions of two adjacent velocity vectors must be located in the same quadrant or two adjacent quadrants. After the vortex is determined, the outermost quasi-closed streamline is used as the vortex boundary, and the average distance from the boundary point to the vortex center is used as the radius of the vortex. This method has been widely used in vortex identification based on high-resolution numerical model results in recent years.

[0004] However, the VG method uses the above four constraints to determine whether the circulation field is closed, which brings some challenges to the identification of vortices. It requires more complex processing and calculation of the ocean current velocity field, which increases the computational complexity of the vortex identification algorithm and the difficulty of engineering implementation. Summary of the Invention

[0005] The present invention provides a method, system, and medium for identifying ocean vortices. This method performs an orthogonal transformation of sea surface current velocities in flow field data, transforming vortex identification from the traditional closed curve problem of the flow field to the problem of identifying convergence and divergence points of the flow field, thereby facilitating efficient identification of ocean vortices.

[0006] The ocean vortex identification method provided by the present invention comprises:

[0007] Obtaining the flow field data of the ocean to be identified, performing an orthogonal transformation on the sea surface flow field in the flow field data, and obtaining a vector field after the orthogonal transformation;

[0008] According to the horizontal scale of the ocean vortex, the algorithm adaptively determines the size of the sliding window, and uses the sliding window to slide the vector field after orthogonal transformation, and the point with the minimum absolute value of the sea surface current velocity within the sliding window is used as the preliminary determination of the center point of the ocean vortex;

[0009] In the sliding window, the boundary distance is determined according to the golden section method with the preliminarily determined center point of the ocean vortex as the center to obtain a new window. When the distance between the boundary of the new window and the original sliding window is greater than the preset distance value, and the number of velocity directions of each sea surface flow field in the new window meets the preset number value, then the new window contains the ocean vortex, and the vortex center of the ocean vortex is calculated by the least squares method.

[0010] Preferably, it also includes:

[0011] When the distance between the boundary of the new window and the original sliding window is less than or equal to a preset value, and / or,

[0012] When the number of one or more surface flow field velocity directions in the new window does not meet the preset value, the sliding window slides to the next window as the new sliding window.

[0013] Preferably, obtaining the vector field after orthogonal transformation includes:

[0014] The U and V directions of the sea surface current velocities in the flow field data are rotated 90° clockwise.

[0015] Preferably, the algorithm adaptively determines the size of the sliding window according to the horizontal scale of the ocean vortex, including:

[0016] According to the data grid point distance L and the vortex horizontal scale D corresponding to the spatial resolution of the ocean flow field data to be identified, D / L is calculated to obtain the moving window size for traversing each data grid point in the ocean vortex flow field after orthogonal transformation.

[0017] Preferably, the step of obtaining a new window by determining a boundary distance based on the golden section method with the initially determined ocean vortex center point as the center within the sliding window comprises:

[0018] Get the sliding window size X, and round up the value of X×ψ to the nearest integer as the new window size, where ψ is the golden ratio;

[0019] A new window is obtained with the preliminarily determined center point of the ocean vortex as the center.

[0020] Preferably, the distance between the boundary of the new window and the original sliding window is greater than a preset distance value, including:

[0021] The preset distance value is close to half of the new window size, and the specific value depends on the flow field data of the ocean to be identified.

[0022] Preferably, the number of velocity directions of each sea surface flow field in the new window satisfies a preset value, including:

[0023] Calculate the sea surface current velocity at each data grid point based on the sea surface current velocity U and V in the new window. , and compare the values Perform positive and negative judgment to obtain the direction of the sea surface current velocity at each data grid point. The directions of the sea surface current velocity include: east, south, west, north, southeast, southwest, northeast, and northwest;

[0024] A histogram of the direction and number of surface current velocity is generated to obtain the number of data grid points for each surface current velocity direction. If the number of data grid points for each surface current velocity direction meets a preset value, then the new window contains an ocean vortex. The preset value depends on the flow field data of the ocean to be identified.

[0025] Preferably, the calculation of the ocean vortex by the least square method comprises:

[0026] The vortex center of the ocean vortex is calculated by calculating the point closest to the intersection of multiple velocity lines in the new window using the least squares method.

[0027] The present invention also provides an ocean vortex identification system for implementing any of the above-mentioned ocean vortex identification methods, wherein the ocean vortex identification system comprises:

[0028] The orthogonal transformation module is used to obtain the flow field data of the ocean to be identified, perform orthogonal transformation on the sea surface flow field in the flow field data, and obtain the vector field after orthogonal transformation;

[0029] The sliding window module is used to adaptively determine the size of the sliding window according to the horizontal scale of the ocean vortex. The orthogonal transformed vector field is traversed through the sliding window, and the point with the minimum absolute value of the sea surface current velocity within the sliding window is used as the preliminary determination of the center point of the ocean vortex.

[0030] The vortex identification module is used to obtain a new window within the sliding window with the preliminarily determined ocean vortex center point as the center, and determine the boundary distance according to the golden section method. When the distance between the boundary of the new window and the original sliding window is greater than the preset distance value, and the number of velocity directions of each sea surface flow field in the new window meets the preset number value, the new window contains an ocean vortex, and the vortex center of the ocean vortex is calculated by the least squares method.

[0031] The present invention also provides a computer-readable storage medium, characterized in that a data processing program is stored on the computer-readable storage medium, and when the data processing program is executed by a processor, the steps of the ocean vortex identification method as described in any one of the above are implemented.

[0032] Compared with the prior art, the present invention performs an orthogonal transformation of the sea surface current velocity in the flow field data, slides and traverses the ocean flow field through a sliding window, determines a new window based on the minimum absolute value point of the sea surface current velocity in the sliding window and the golden section method, and presets the position of the new window to ensure that there is enough space around the center point of the new window for further analysis without being excessively disturbed by the surrounding environment. The number of directions of each sea surface current velocity in the new window is preset, the ocean vortex is identified, and the vortex center of the ocean vortex is calculated by the least squares method. The present invention omits the step of using four constraints in the traditional VG method to determine whether the circulation field is closed to identify the vortex, and transforms the vortex identification from the traditional flow field closed curve problem to the problem of identifying the flow field convergence and divergence points, and the identification method is simpler. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a flow chart of the ocean vortex identification method provided by the first embodiment of the present invention.

[0034] Figure 2 Schematic diagram of the ocean flow field and sliding window provided by the first embodiment of the present invention.

[0035] Figure 3 1 is the UV vector diagram before and after the orthogonal transformation provided by the first embodiment of the present invention.

[0036] Figure 4 It is a histogram of the direction and quantity of sea surface current velocity in the new window provided by the first embodiment of the present invention.

[0037] Figure 5 Schematic diagram of the vortex center of the ocean vortex provided by the first embodiment of the present invention.

[0038] Figure 6 This is a flow chart of an implementation of the ocean vortex identification method provided by the second embodiment of the present invention. DETAILED DESCRIPTION

[0039] The following description sets forth many specific details to facilitate a thorough understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar generalizations without violating the scope of the present application. Therefore, the present application is not limited to the specific implementations disclosed below.

[0040] The first embodiment of the present application provides a method for identifying ocean vortices. Figure 1 , which is a flow chart of the first embodiment of this application. Figures 1-4 The method provided in the first embodiment of the present application is described in detail.

[0041] Step S101, obtaining flow field data of the ocean to be identified, performing an orthogonal transformation on the sea surface flow field in the flow field data to obtain an orthogonally transformed vector field;

[0042] This step is used to obtain the orthogonal transformed vector field of the ocean flow to be identified through orthogonal transformation, and transform the identification of vortices from the traditional flow field closed curve problem to the problem of identifying the flow field convergence and divergence points, so as to better identify vortices.

[0043] In complex flow field structures, vortices may exhibit a variety of forms and characteristics. Traditional closed curve analysis may have difficulty accurately identifying the location, form, and intensity of vortices. For very complex flow field structures, it may not even be possible to fully capture the characteristics of the vortex. At the same time, noise and interference often exist in the flow field. These factors may affect the accuracy of the traditional flow field closed curve method, resulting in the misjudgment or omission of vortices. In contrast, convergence points and divergence points directly reflect the convergence and dispersion of fluids in the flow field, corresponding to the core area of ​​the vortex and the surrounding environment. By identifying convergence points and divergence points, the location, form, and intensity of the vortex can be more intuitively represented, which is applicable to various flow field forms and vortex structures. Identifying flow field convergence and divergence points is simpler and more intuitive than traditional closed curve analysis, because convergence and divergence points can be determined by calculating the gradient of the flow field or other mathematical methods, without the need for complex curve analysis.

[0044] Obtaining the ocean vortex flow field after orthogonal transformation includes: rotating the sea surface current velocity U direction and V direction in the flow field data by 90 degrees clockwise.

[0045] In step S102, the algorithm adaptively determines the size of the sliding window according to the horizontal scale of the ocean vortex, and slides the vector field after orthogonal transformation through the sliding window, and takes the point with the minimum absolute value of the sea surface current velocity in the sliding window as the preliminarily determined center point of the ocean vortex.

[0046] This step is used to obtain a sliding window, traverse the ocean flow field, and preliminarily determine the center point of the ocean vortex.

[0047] According to the horizontal scale of the ocean eddy, the algorithm adaptively determines the size of the sliding window including:

[0048] According to the data grid point distance L and the vortex horizontal scale D corresponding to the spatial resolution of the ocean flow field data to be identified, D / L is calculated to obtain the moving window size for traversing each data grid point in the ocean vortex flow field after orthogonal transformation.

[0049] The spatial resolution of ocean current data is typically expressed by the distance between data grid points. This depends on how the data is collected and processed, and different data sources and processing methods may result in different data grid distances. For example, for flow data with a spatial resolution of 1°, the distance L between each data grid point is 10 km. Given that mesoscale eddies can reach hundreds of kilometers in size, the window size, calculated based on the D / L ratio, is 10*10. Odd values ​​are generally used, resulting in an 11*11 sliding window.

[0050] In the ocean, vortices usually cause local flow velocity changes, especially around the center of the vortex, where the flow velocity is lower, while the edge of the vortex may have a higher flow velocity. This is because vortices cause the water flow to rotate, resulting in differences in flow velocity. The point with the smallest absolute value of flow velocity usually corresponds to a stationary point in the local flow field or an area with small flow velocity changes. In the central area of ​​the vortex, the flow velocity changes less, so the point with the smallest absolute value of flow velocity may be the center of the vortex. Taking the point with the smallest absolute value of flow velocity as the preliminary determination of the vortex center point is a reasonable estimation method in the technical solution of the present invention, and the vortex center point is determined in combination with the further refined processing described below.

[0051] Please see Figure 2 (a) This figure is a schematic diagram of the ocean flow field. The sliding window is determined according to the horizontal scale of the ocean vortex. The sliding window slides across the ocean flow field. The figure contains a large number of data grid points. Figure 2 (b) is a schematic diagram of the sliding window in the ocean current field. The size of the sliding window is obtained by calculating D / L based on the data grid distance L corresponding to the spatial resolution of the ocean current data to be identified and the horizontal scale size D of the vortex.

[0052] Please see Figure 3 (a) This figure is the UV vector diagram of the ocean flow field velocity. The velocity data of the ocean flow field includes the horizontal velocity U and the vertical velocity V. The U and V velocity data are converted into a velocity vector field. Arrows are usually used to represent vectors. The length and direction of the arrows represent the magnitude and direction of the velocity. The outer arrows in the figure are longer, indicating a large velocity. The length of the arrow at the center is the shortest, indicating the minimum velocity, which is used as the preliminary determination of the vortex center point. Figure 3 (a) The surface current velocity in the U and V directions of the flow field data is rotated 90° clockwise to obtain Figure 3 (b) This figure is the velocity UV vector diagram after orthogonal transformation of the ocean flow field.

[0053] Step S103, taking the preliminarily determined ocean vortex center point as the center in the sliding window, determine the boundary distance according to the golden section method to obtain a new window. When the distance between the boundary of the new window and the original sliding window is greater than the preset distance value, and the number of velocity directions of each sea surface flow field in the new window meets the preset number value, then the new window contains the ocean vortex, and the vortex center of the ocean vortex is calculated by the least squares method.

[0054] This step is used to obtain a more accurate new window within the sliding window. By setting two preset conditions, the distance between the boundary of the new window and the original sliding window is greater than the preset distance value, and the number of each sea surface current velocity direction in the new window meets the preset number value, a new window containing an ocean vortex is obtained, and the vortex center of the ocean vortex is obtained.

[0055] In the sliding window, the center of the initially determined ocean vortex is taken as the center, and the boundary distance is determined according to the golden section method to obtain a new window including:

[0056] Get the sliding window size X, The rounded-up value is the new window size, where It is the golden ratio; a new window is obtained with the preliminarily determined center point of the ocean vortex as the center.

[0057] The golden section method is an optimization algorithm that uses the golden ratio to determine the boundary distance, ensuring that the size of the new window fully covers the possible range of the vortex. Within the sliding window, the boundary distance is determined according to the golden section method, centered on the initially determined center of the ocean vortex. Once the new window is obtained, the velocity data within the new window can be further analyzed and processed to extract the complete characteristics of the vortex.

[0058] At this time, the preset condition is that the distance between the boundary of the new window and the original sliding window is greater than the preset distance value, including:

[0059] The preset distance value is close to half of the new window size, and the specific value depends on the flow field data of the ocean to be identified.

[0060] By adjusting the preset distance value, it is ensured that the distance between the boundary of the new window and the original sliding window meets expectations or meets specific requirements. The specific effect is that during the vortex identification and analysis process, the surrounding flow field data may affect the identification and boundary determination of the new window, especially for small-scale or local flow field features. By determining the size of the new window through the golden section method and controlling the boundary distance through preset distance conditions to keep the center of the new window close to the center of the sliding window and perform more precise analysis around the vortex features, the position range of the new window can be better controlled, unnecessary external influences can be eliminated, and the data of the new window can be ensured to mainly reflect the vortex features, thereby improving the accuracy and reliability of vortex identification.

[0061] Please see Figure 3 (b) This figure shows the UV vector diagram of the ocean flow field after orthogonal transformation. The dotted arrow area in the figure represents the flow field outside the sliding window, the thin solid arrow area represents the flow field inside the sliding window, and the thick solid arrow area represents the flow field inside the new window.

[0062] After determining the position of the new window within the sliding window, another preset condition is that the number of each sea surface current velocity direction within the new window meets the preset value. When performing vortex analysis, the reliability of the statistical analysis can be improved if the number of each sea surface current velocity direction within the new window reaches the preset value. If the number of a certain direction is too small or non-existent, it may be due to the following situations: the velocity data in this direction is not fully captured by the new window, which may result in the boundary of the vortex not being fully covered, affecting the identification and boundary determination of the vortex; the vortex characteristics in this direction are not obvious or do not exist. The identification of vortices requires certain flow field change characteristics. If the flow velocity changes in a certain direction are small or gentle, it may not meet the characteristic requirements of the vortex.

[0063] Therefore, it is necessary to determine the direction of each sea surface current velocity in the new window to ensure that the ocean eddies are included in the new window.

[0064] The number of each sea surface current velocity direction in the new window satisfies a preset number value, including:

[0065] According to the sea surface current velocities U and V in the new window, the sea surface current velocity of each data grid point is calculated. , and compare the values Perform positive and negative judgment to obtain the direction of the sea surface current velocity at each data grid point. The directions of the sea surface current velocity include: east, south, west, north, southeast, southwest, northeast, and northwest;

[0066] A histogram of the surface current velocity direction and quantity is plotted to obtain the number of data grid points for each surface current velocity direction. If the number of data grid points for each surface current velocity direction meets a preset value, then the new window contains an ocean vortex, where the preset value depends on the flow field data of the ocean to be identified.

[0067] Please see Figure 4 This figure is a histogram of the direction and amount of sea surface current velocity in the new window. The figure includes eight directions: east, south, west, north, southeast, southwest, northeast, and northwest.

[0068] As mentioned above, the new window obtained in the sliding window needs to meet two preset conditions.

[0069] The distance between the boundary of the opening and the original sliding window is greater than the preset distance value, and the number of each sea surface current velocity direction in the new window meets the preset number value to obtain a new window containing ocean vortices.

[0070] When the distance between the boundary of the new window and the original sliding window is less than or equal to the preset value, and / or the new window

[0071] If the number of surface current velocity directions in the inlet does not meet the preset value, the sliding window slides to the next window as a new sliding window. The sliding window slides through the ocean flow field to find a new window containing an ocean vortex that meets the two preset conditions.

[0072] After obtaining a new window containing the ocean vortex, the vortex center of the ocean vortex is calculated by the least square method, including: calculating the point closest to the intersection of multiple velocity lines in the new window by the least square method as the vortex center of the ocean vortex. Figure 5 , which is a schematic diagram of the vortex center of an ocean vortex.

[0073] According to the method provided in the first embodiment, the second embodiment of the present invention provides a specific application example of the ocean vortex identification method for a certain sea area where mesoscale vortices often appear.

[0074] Also, see Figure 6 This figure is a flowchart for implementing the ocean eddy identification method. Flow field data for a specific ocean area is obtained. The meridional and zonal components of the surface current velocity (U and V) are read. The surface current velocity in the flow field data is rotated 90° clockwise in both directions to obtain the orthogonal transformed ocean current field.

[0075] For flow field data with a spatial resolution of 1°, the distance L between each data grid point is 10 km. For mesoscale eddies with a horizontal scale of hundreds of kilometers, the window size is 10*10 according to D / L calculation. An odd value is generally used, so the sliding window is an 11*11 window. Create an 11*11 sliding window and slide it across the flow field.

[0076] Through the min function, find the point with the minimum absolute value of the sea surface current velocity in the sliding window, and use this point as

[0077] The center is determined by the golden section method to obtain a small 7*7 window.

[0078] At this time, half of the new window size is calculated as (71) / 2=3, which is 3 in this embodiment. The preset number of each surface current velocity direction in the new window is 2. When the preset distance and the preset number are both satisfied, the new window contains an ocean vortex, and the vortex center of the ocean vortex is calculated by the least squares method. When the distance between the boundary of the new window and the original sliding window is less than or equal to the preset value, and / or the number of one or more surface current velocity directions in the new window does not meet the preset value, the sliding window slides to the next window as a new sliding window. When a new window containing an ocean vortex is obtained, the vortex center of the ocean vortex is calculated by the least squares method.

[0079] A third embodiment of the present invention provides an ocean vortex identification system, comprising:

[0080] The orthogonal transformation module is used to obtain the flow field data of the ocean to be identified, perform orthogonal transformation on the sea surface flow field in the flow field data, and obtain the vector field after orthogonal transformation;

[0081] The sliding window module is used to adaptively determine the size of the sliding window according to the horizontal scale of the ocean vortex. The orthogonal transformed vector field is traversed through the sliding window, and the point with the minimum absolute value of the sea surface current velocity within the sliding window is used as the preliminary determination of the center point of the ocean vortex.

[0082] The vortex identification module is used to obtain a new window within the sliding window with the preliminarily determined ocean vortex center point as the center, and determine the boundary distance according to the golden section method. When the distance between the boundary of the new window and the original sliding window is greater than the preset distance value, and the number of velocity directions of each sea surface flow field in the new window meets the preset number value, the new window contains an ocean vortex, and the vortex center of the ocean vortex is calculated by the least squares method.

[0083] A fourth embodiment of the present invention provides a computer-readable storage medium, characterized in that a data processing program is stored on the computer-readable storage medium, and when the data processing program is executed by a processor, the steps of the ocean vortex identification method as described in any one of the above are implemented.

[0084] Although the present application is disclosed as above with the preferred embodiments, it is not intended to limit the present application. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present application. Therefore, the scope of protection of the present application shall be based on the scope defined by the claims of the present application.

Claims

1. A method for identifying ocean vortices, characterized in that: include: Obtaining the flow field data of the ocean to be identified, performing an orthogonal transformation on the sea surface flow field in the flow field data, and obtaining a vector field after the orthogonal transformation; According to the horizontal scale of the ocean vortex, the algorithm adaptively determines the size of the sliding window, and uses the sliding window to slide the vector field after orthogonal transformation, and the point with the minimum absolute value of the sea surface current velocity within the sliding window is used as the preliminary determination of the center point of the ocean vortex; In the sliding window, the boundary distance is determined according to the golden section method with the preliminarily determined center point of the ocean vortex as the center to obtain a new window. When the distance between the boundary of the new window and the original sliding window is greater than the preset distance value, and the number of velocity directions of each sea surface flow field in the new window meets the preset number value, the new window contains the ocean vortex, and the vortex center of the ocean vortex is calculated by the least squares method; The obtaining of the vector field after orthogonal transformation includes: Rotate the sea surface current velocity in the U and V directions of the flow field data by 90° clockwise; The algorithm adaptively determines the size of the sliding window according to the horizontal scale of the ocean vortex, including: According to the data grid point distance L and the vortex horizontal scale D corresponding to the spatial resolution of the ocean flow field data to be identified, D / L is calculated to obtain the moving window size for traversing each data grid point in the ocean vortex flow field after orthogonal transformation.

2. A method for identifying ocean vortices according to claim 1, characterized in that: Also includes: When the distance between the boundary of the new window and the original sliding window is less than or equal to a preset value, and / or, When the number of one or more surface flow field velocity directions in the new window does not meet the preset value, the sliding window slides to the next window as the new sliding window.

3. A method for identifying ocean vortices according to claim 1, characterized in that: The step of obtaining a new window by determining the boundary distance based on the golden section method with the initially determined ocean vortex center point as the center within the sliding window includes: Get the sliding window size X, and round up the value of X×ψ to the nearest integer as the new window size, where ψ is the golden ratio; A new window is obtained with the preliminarily determined center point of the ocean vortex as the center.

4. A method for identifying ocean vortices according to claim 1, characterized in that: The distance between the boundary of the new window and the original sliding window is greater than a preset distance value, including: The preset distance value is close to half of the new window size, and the specific value depends on the flow field data of the ocean to be identified.

5. The method for identifying ocean vortices according to claim 1, wherein: The number of velocity directions of each sea surface flow field in the new window satisfies a preset number value, including: Calculate the sea surface current velocity at each data grid point based on the sea surface current velocity U and V in the new window. , and compare the values Perform positive and negative judgment to obtain the direction of the sea surface current velocity at each data grid point. The directions of the sea surface current velocity include: east, south, west, north, southeast, southwest, northeast, and northwest; A histogram of the direction and number of surface current velocity is generated to obtain the number of data grid points for each surface current velocity direction. If the number of data grid points for each surface current velocity direction meets a preset value, then the new window contains an ocean vortex. The preset value depends on the flow field data of the ocean to be identified.

6. A method for identifying ocean vortices according to claim 1, characterized in that: The calculation of ocean vortex by least square method includes: The vortex center of the ocean vortex is calculated by calculating the point closest to the intersection of multiple velocity lines in the new window using the least squares method.

7. An ocean vortex identification system, characterized in that: For implementing the ocean vortex identification method according to any one of claims 1 to 6, the ocean vortex identification method system comprises: The orthogonal transformation module is used to obtain the flow field data of the ocean to be identified, perform orthogonal transformation on the sea surface flow field in the flow field data, and obtain the vector field after orthogonal transformation; The sliding window module is used to adaptively determine the size of the sliding window according to the horizontal scale of the ocean vortex. The orthogonal transformed vector field is traversed through the sliding window, and the point with the minimum absolute value of the sea surface current velocity within the sliding window is used as the preliminary determination of the center point of the ocean vortex. The vortex identification module is used to obtain a new window within the sliding window with the preliminarily determined ocean vortex center point as the center, and determine the boundary distance according to the golden section method. When the distance between the boundary of the new window and the original sliding window is greater than the preset distance value, and the number of velocity directions of each sea surface flow field in the new window meets the preset number value, the new window contains an ocean vortex, and the vortex center of the ocean vortex is calculated by the least squares method.

8. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a data processing program, which, when executed by a processor, implements the steps of the ocean vortex identification method according to any one of claims 1 to 6.

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