A method for analyzing energy conversion of mesoscale eddies in the ocean

Abstract

The application discloses a kind of mesoscale eddy energy conversion analysis methods in ocean, it is related to ocean dynamics technical field.The method is first based on satellite remote sensing and observation data to determine target eddy basic characteristics and obtain high-resolution gridding data, utilize eddy detection algorithm to determine eddy center and boundary, then track algorithm is constructed trajectory;Second, with baroclinic conversion term and barotropic conversion term quantifying eddy and average flow energy conversion;Finally, using eddy kinetic energy budget equation quantifies barotropic instability, baroclinic conversion, wind stress input and the contribution of other dynamic terms to eddy kinetic energy.The method improves the detection precision of weak amplitude and short life eddy, realizes the quantitative calculation of eddy energy exchange, and can be widely applied to eddy energy budget analysis.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ocean dynamics, and particularly relates to a mesoscale eddy energy conversion analysis method. BACKGROUND

[0002] As a key dynamic process in the ocean, the energy conversion mechanism of mesoscale eddy is of great significance to the ocean circulation and climate system. However, in the quantitative analysis of eddy energy, the existing technology is mostly limited to the calculation of single kinetic energy, potential energy or single mechanism, and cannot completely describe the energy conversion process. At the same time, the adaptability of the detection and tracking method is insufficient, resulting in deviation of the analysis results.

[0003] Specifically, in the analysis of the energy conversion mechanism of mesoscale eddy, the existing research mostly uses eddy detection methods based on preset amplitude or single physical characteristics (such as the commonly used OW method). Such methods do not fully consider the propagation characteristics of Rossby waves, and are prone to cause the breaking or false merging of eddy trajectories. Moreover, the fixed threshold detection algorithm is difficult to capture weak amplitude or short-lived eddies, thereby causing deviation in the energy budget statistics.

[0004] In terms of eddy energy and dynamic mechanism analysis, the existing research often only separates and calculates single kinetic energy or potential energy, single dynamic mechanism. This approach will cause the loss of energy coupling within the eddy, such as the independent analysis of baroclinic and barotropic conversion processes, ignoring the dynamic influence of the synergistic effect of the two on the eddy life cycle. Although some scholars try to introduce data assimilation or machine learning technology to improve the identification and tracking of eddies, and based on this, to analyze the energy of eddies, these methods have the problem of high computational complexity, and the analysis results have strong dependence on the universality of the training data. SUMMARY

[0005] The purpose of the present application is to provide a mesoscale eddy energy conversion analysis method, which realizes high-precision and systematic analysis of mesoscale eddy energy conversion through the whole process quantification of coupling detection-tracking-energy budget equation.

[0006] To achieve the above purpose, the present application provides a mesoscale eddy energy conversion analysis method, the steps are as follows:

[0007] Step S1, based on satellite remote sensing and observation data, determine the basic characteristics of the target mesoscale eddy, download high-resolution gridded data with a time and space range greater than the estimated area, and perform data preprocessing;

[0008] Step S2: use the eddy detection algorithm to detect the target mesoscale eddy, determine the center and boundary range of the eddy;

[0009] Step S3: Based on the detection result in step S2, the target mesoscale vortex is tracked by using a vortex tracking algorithm;

[0010] Step S4: The vortex kinetic energy EKE and the vortex effective potential energy EPE are calculated by using the high-resolution gridded data obtained in step S1;

[0011] Step S5: The energy conversion process is quantified by the baroclinic conversion term T2 and the barotropic conversion term T4, and the energy conversion between the vortex energy and the mean flow energy is calculated;

[0012] Step S6: The kinetic energy budget equation is constructed, and the contributions of barotropic instability BTC, baroclinic energy conversion VEDF, wind stress input WW, pressure work PW, and advection ADV to the vortex kinetic energy are calculated;

[0013] Step S7: The time series of each term is generated by deep integration and spatial averaging, and the quantitative calculation of vortex energy exchange is realized.

[0014] Preferably, in step S1, the downloaded data range is slightly larger than the estimated range in both time and spatial scales, and the collected data is preprocessed, and the data is interpolated to the standard layer in depth.

[0015] Preferably, in step S2, the specific steps of the vortex detection algorithm are:

[0016] Step S21, based on the sea surface height anomaly SLA data provided by the satellite altimeter, in the daily data snapshot, the local maximum and minimum are identified by 5x5 neighborhood search;

[0017] Step S22, noise filtering is performed on the extreme value points, including: removing noise interference by 3x3 neighborhood; verifying the validity of the extreme value points by 7x7 neighborhood;

[0018] Step S23, taking the extreme value point as the starting point, the iterative threshold method is used to expand outward, the iterative step length is 0.05 cm, the closed loop contour is calculated, and the termination condition is met until the termination condition is met;

[0019] Step S24, the vortex boundary is determined by the reverse rollback method;

[0020] Step S25, the closed vortex structure with spatial resolution not less than 0.25°x0.25° and grid number≥4 is reserved.

[0021] Preferably, in step S23, the termination conditions include: new extreme value points appear in the closed loop region; the number of iterations of the extreme value points no longer increases; the closed loop contour cannot be continuously expanded.

[0022] Preferably, in step S3, the main steps of vortex tracking are:

[0023] Step S31, define the search range of vortex propagation based on Rossby phase velocity theory, and preferentially match the spatiotemporal nearest neighbor vortex to construct a trajectory;

[0024] Step S32, constrain the vortex matching conditions of adjacent time t and t+1 through attribute consistency test, including: controlling the vortex area change amplitude in the range of 0.25-2.75 times; controlling the vortex amplitude change amplitude in the range of 0.25-2.75 times;

[0025] Step S33, for the vortex with a disappearance time less than 1 day, insert a virtual vortex node to maintain the continuity of the trajectory, and calculate the position of the virtual node by linear extrapolation interpolation of the historical propagation speed;

[0026] Step S34, remove the virtual vortex node in the final trajectory data.

[0027] Preferably, in step S4, the calculation method of the vortex kinetic energy EKE and the vortex effective potential energy EPE is as follows:

[0028] Step S41, extract the zonal and meridional components of the horizontal flow field and , and define the background field of the flow velocity component and the change rate within the vortex duration 、 , decompose the original flow velocity, and the calculation relationship of each parameter is as follows:

[0029] ;

[0030] ;

[0031] wherein, is the zonal component change rate of the flow velocity, is the zonal component of the background field flow velocity, is the meridional component change rate of the flow velocity, is the meridional component of the background field flow velocity;

[0032] Step S42, the calculation formula of the vortex kinetic energy EKE is as follows:

[0033] ;

[0034] wherein, is the reference density;

[0035] Step S43, calculate the seawater density based on the seawater state equation UNESCO EOS-80 using the temperature, salinity and pressure data of seawater and the potential density of the background field The background density related to depth is obtained by spatially averaging the research area and time-averaging during the existence of the vortex, and the perturbation density is calculated, with the formula as follows:

[0036] = - ;

[0037] wherein, is the perturbation density, is the background density related to depth, is the longitude coordinate, is the latitude coordinate, is the depth, is the time.

[0038] Step S44, the effective potential energy of the vortex at each grid point in the vortex range is calculated, with the formula as follows:

[0039] ;

[0040] wherein, is the gravitational constant, is the change rate of the perturbation density, is the density, is the background field potential density.

[0041] Preferably, in step S5, the baroclinic conversion term T2 is calculated with the formula as follows:

[0042] ;

[0043] wherein, is the background field perturbation density;

[0044] The barotropic conversion term T4 is calculated with the formula as follows:

[0045] .

[0046] Preferably, in step S6, the kinetic energy budget equation is constructed, with the formula as follows:

[0047] ;

[0048] wherein, represents the time change rate of the vortex kinetic energy;

[0049] ;

[0050] ;

[0051] ;

[0052] ;

[0053] ;

[0054] wherein, is the vertical velocity change rate, is the directional wind stress component change rate, is the directional wind stress component change rate, is the sea water pressure change rate;

[0055] Preferably, the wind stress directional component and directional component are calculated according to the following formula:

[0056] ;

[0057] ;

[0058] wherein, is the wind speed at sea level 10m, , and are the wind speeds in the direction and direction of the sea surface 10m wind field respectively, is the drag coefficient, and the calculation method is as follows:

[0059] .

[0060] Preferably, in step S7, the vortex internal time sequence calculation steps of each term are as follows:

[0061] Step S71, according to the vortex range at each time point obtained in step S3, the grid points inside and outside the vortex are determined;

[0062] Step S72, selecting the depth within the vortex influence range, depth integration is carried out at the grid points inside the vortex;

[0063] Step S73, spatially averaging the integration results of the grid points inside the vortex at each time, the time sequence of each term is obtained.

[0064] Therefore, the present application proposes a mesoscale vortex energy conversion analysis method in the ocean, which has the following beneficial effects:

[0065] (1) Strong adaptability: the present application adopts the iterative threshold method and the dynamic noise filtering technology, without presetting the vortex amplitude or life threshold, can accurately identify mesoscale vortexes of different intensity and scale, and is especially suitable for the detection of weak signal vortexes;

[0066] (2) High physical consistency: Based on the Rossby phase speed theory to constrain the vortex tracking search range, combined with the virtual node interpolation technology, to ensure the spatiotemporal continuity of the vortex trajectory, and to avoid false merging or breaking;

[0067] (3) Comprehensive energy coupling analysis: Through the joint calculation of baroclinic conversion term (T2) and barotropic conversion term (T4), the energy exchange between vortex and background flow is quantified, and the limitation of traditional method which only focuses on single energy or dynamic mechanism form is overcome;

[0068] (4) Optimization of calculation efficiency: The layered depth integration and vortex grid space average strategy are adopted to reduce the data operation amount while ensuring the accuracy, which is suitable for large-scale long-time sequence analysis;

[0069] (5) Wide application range: The method can be compatible with satellite altimeter, reanalysis data and field observation data, and provides a general technical framework for ocean circulation diagnosis and vortex-climate interaction research.

[0070] The technical solutions of the present application will be further described in detail below with the help of the accompanying drawings and embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0071] Figure 1 is a flow chart of the mesoscale vortex energy conversion analysis method in the present application;

[0072] Figure 2 is a schematic diagram of the vortex-averaged time series of each dynamic mechanism in the embodiment of the present application; wherein, Figure 2 a is the vortex-averaged time series of PW in the schematic diagram, Figure 2 b is the vortex-averaged time series of BTC and WW in the schematic diagram, Figure 2 c is the vortex-averaged time series of ADV in the schematic diagram, Figure 2 d is the vortex-averaged time series of VEDF in the schematic diagram. DETAILED DESCRIPTION

[0073] In order to make the technical solutions, advantages and purposes of the present application clearer, the technical solutions of the embodiments of the present application will be described clearly and completely below. The described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the described embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0074] Unless otherwise defined, the technical terms or scientific terms used in the present application shall have the usual meanings understood by those skilled in the art to which the present application belongs.

[0075] Embodiment one

[0076] This embodiment selects a 2009-2010 winter and spring long-distance migration anticyclone vortex in a certain sea area, determines the basic situation of the target mesoscale vortex based on satellite remote sensing data, roughly estimates that the spatial range of the life cycle of the anticyclone vortex is between 16°N and 21°N and 111°E and 121°E, and the time range is from December 2009 to April 2010, and the energy conversion calculation of the anticyclone vortex is carried out.

[0077] As shown in Figure 1 The flow chart of the energy conversion analysis method of the mesoscale vortex in the sea according to the present application is shown in the figure, and the specific steps are as follows:

[0078] S1, collect high-resolution reanalysis gridded data with a time and space range greater than the estimated area (a rectangular area of 15°N to 22°N, 110°E to 122°E, from November 2009 to May 2010), and perform data preprocessing, and vertically interpolate the 50-layer 0.083°×0.083° high-resolution data provided by the reanalysis data to the standard layer.

[0079] S2, the target mesoscale vortex is detected by using a vortex detection algorithm, and the center and boundary range of the vortex are determined, and the steps are as follows:

[0080] Firstly, based on the sea surface height anomaly (SLA) data provided by the satellite altimeter, in the daily data snapshot, the local maximum value (anticyclone vortex) is identified by 5×5 neighborhood search.

[0081] Then, the extreme value point is filtered, and the noise interference is removed by 3×3 neighborhood; the effectiveness of the extreme value point is verified by 7×7 neighborhood, and the false detection rate is reduced; then the extreme value point is taken as the starting point, and the iterative threshold method is used to expand outward, the iterative step is 0.05cm, the closed loop contour is calculated, and the following termination conditions are met: a new extreme value point appears in the closed loop area; the iteration number of the extreme value point does not increase; the closed loop contour cannot be continuously expanded;

[0082] Finally, the vortex boundary is determined by the reverse rollback method to avoid the false detection caused by the merging of adjacent vortexes; and the closed vortex structure with a spatial resolution not less than 0.25°×0.25° and a grid number ≥4 is retained, and no amplitude or life threshold is preset to adapt to different marine vortex characteristics.

[0083] S3, based on the vortex detection results at each time obtained in S2, the target mesoscale vortex is tracked by using a vortex tracking algorithm, and the steps are as follows:

[0084] Firstly, based on the Rossby phase velocity theory, the search range of the vortex propagation is limited, and the nearest adjacent vortex in space and time is matched to construct the trajectory;

[0085] Then, the vortex matching condition of adjacent time (t and t+1) is constrained by the attribute consistency test, including: the vortex area change amplitude is controlled within the range of 0.25-2.75 times; the vortex amplitude change amplitude is controlled within the range of 0.25-2.75 times; in addition, for the vortex that disappears temporarily (disappearance time ≤1 day), a virtual vortex node is inserted to maintain the trajectory continuity, and the virtual node position is calculated by using linear extrapolation interpolation with the historical propagation speed;

[0086] Finally, the virtual node is removed in the final trajectory data to ensure physical consistency.

[0087] S4, calculate the vortex kinetic energy EKE and the vortex effective potential energy EPE using the high-resolution gridded data obtained in step S1, the specific calculation method is as follows:

[0088] S41, extract the zonal and meridional components of the horizontal flow field and , and define the background field of the flow velocity component and the change rate within the vortex duration , , decompose the original flow velocity, and the calculation relationship of each parameter is as follows:

[0089] ;

[0090] ;

[0091] Among them, is the zonal component change rate of the flow velocity, is the zonal component of the background flow velocity, is the meridional component change rate of the flow velocity, is the meridional component of the background flow velocity;

[0092] S42, the calculation formula of the vortex kinetic energy EKE is as follows:

[0093] ;

[0094] Among them, is the reference density, which is taken as ;

[0095] S43, calculate the seawater density based on the seawater state equation UNESCO EOS-80 using the temperature, salinity and pressure data of seawater and the potential density of the background field ; by spatially averaging the study area and temporally averaging during the vortex existence period, the background density related to depth is obtained, and the perturbation density is calculated, the formula is as follows:

[0096] = - ;

[0097] where, is the perturbation density, is the background density related to depth, is the longitude coordinate, is the latitude coordinate, is the depth at which, is the time;

[0098] S44, the effective potential energy of the vortex at each grid point in the vortex range is calculated, and the formula is as follows:

[0099] ;

[0100] where, is the gravitational constant, is the rate of change of the perturbation density, is the density, is the background field potential density.

[0101] S5, the energy conversion process is quantified by the baroclinic conversion term T2 and the barotropic conversion term T4, and the energy conversion between the vortex energy and the average flow energy is calculated;

[0102] The formula for calculating the baroclinic conversion term T2 is as follows:

[0103] ;

[0104] where, is the background field perturbation density;

[0105] The formula for calculating the barotropic conversion term T4 is as follows:

[0106] .

[0107] T2 represents the conversion between the average potential energy of the background flow and the effective potential energy of the vortex, and T4 represents the work done by the Reynolds stress on the average shear, which is the conversion between the average kinetic energy of the background flow and the kinetic energy of the vortex; The positive values of the two indicate the occurrence of baroclinic instability and barotropic instability, so as to evaluate the energy conversion between the vortex and the background flow.

[0108] S6: as shown in Figure 2 , the kinetic energy balance equation is constructed, and the contributions of barotropic instability BTC, baroclinic conversion VEDF, wind stress input WW, pressure work PW and advection ADV to the vortex kinetic energy are calculated;

[0109] Wherein, the formula for constructing the kinetic energy balance equation is as follows:

[0110] ;

[0111] where, represents the time rate of change of the eddy kinetic energy;

[0112] The barotropic conversion BTC describes the conversion of the background flow mean kinetic energy into the eddy kinetic energy, and if this term is positive, it indicates that barotropic instability occurs, and the formula is as follows:

[0113] ;

[0114] The baroclinic conversion VEDF represents the baroclinic conversion caused by the vertical eddy vorticity flux, i.e. the conversion of the eddy potential energy EPE into the EKE, and the calculation formula is as follows:

[0115] ;

[0116] The wind stress input WW represents the EKE generation caused by the sea surface wind stress input, and this term links the time-varying surface wind stress and the ocean circulation, and the calculation formula is as follows:

[0117] ;

[0118] The pressure work PW and the advection ADV respectively represent the redistribution of the EKE through the pressure work and the ocean advection process, and based on the constructed kinetic energy budget equation, the common difference method in fluid mechanics is used to solve, to calculate the spatial and temporal distribution and changes of the action of each dynamic mechanism in the vortex, and the calculation formula is as follows:

[0119] ;

[0120] ;

[0121] where, is the vertical velocity change rate, is the direction wind stress component change rate, is the direction wind stress component change rate, is the sea water pressure change rate;

[0122] In the calculation formula of the wind stress input WW, the wind stress direction component and direction component are calculated as follows:

[0123] ;

[0124] ;

[0125] where, V10 is the wind speed at sea level 10 m, , and V10 is the wind speed at sea level 10 m, V10 is the wind speed at sea level 10 m, V10 is the wind speed at sea level 10 m, C is the drag coefficient, and the calculation method is as follows:

[0126] .

[0127] S7: According to the vortex range at each time point obtained in S3, the grid points inside and outside the vortex are determined, a data mask grid is established, the points inside the vortex are filled with 1, and the points outside the vortex are filled with 0. The depth in the main influence range of the vortex is selected, and the depth integration is performed at the grid points inside the vortex (i.e. at the points where the logical judgment is 1). In this embodiment, the depth integration is performed above 500 m. The integration results of the grid points inside the vortex at each time point are spatially averaged to obtain the final time series of the vortex-averaged energy inside the vortex. Through the depth integration and spatial averaging, the energy source and dissipation mechanism are analyzed based on the quantitatively calculated energy inside the vortex and the vortex-averaged time series of each dynamic term.

[0128] It should be noted that the contents not described in detail in the present application are all prior art and are well known to those skilled in the art.

[0129] Therefore, the present application provides a mesoscale vortex energy conversion analysis method in the ocean, which realizes quantitative analysis of the energy conversion process in the life cycle of the mesoscale vortex through coupling analysis of the multi-scale dynamic constraint adaptive detection algorithm and the energy budget equation, improves the detection accuracy of weak amplitude and short life vortex, systematically analyzes the energy exchange mechanism between the vortex and the background flow, and is suitable for vortex energy budget analysis and research on the influence of the vortex on the climate system.

[0130] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application but not to limit them, and although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can still be modified or replaced by equivalents, and these modifications or replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present application.

Claims

1. A method of mesoscale eddy energy conversion analysis in the ocean, characterized by, The steps are as follows: Step S1, based on satellite remote sensing and observation data, determine the basic characteristics of the target mesoscale vortex, download high-resolution gridded data with a time and space range greater than the estimated area, and perform data preprocessing; Step S2: Use the vortex detection algorithm to detect the target mesoscale vortex, and determine the center and boundary range of the vortex; Step S3: Based on the detection results in step S2, use the vortex tracking algorithm to track the target mesoscale vortex; Step S4: Use the high-resolution gridded data obtained in step S1 to calculate the vortex kinetic energy EKE and the vortex effective potential energy EPE; Step S5: Quantify the energy conversion process through the baroclinic conversion term T2 and the barotropic conversion term T4, and calculate the energy conversion between the vortex energy and the average flow energy; Step S6: Construct the kinetic energy budget equation, calculate the barotropic instability BTC, the baroclinic conversion VEDF, the wind stress input WW, the pressure work PW, and the advection effect ADV on the vortex kinetic energy; Step S7: Through deep integration and spatial averaging, generate the time series of each item, and realize the quantitative calculation of vortex energy exchange; In step S2, the specific steps of the vortex detection algorithm are as follows: Step S21, based on the sea surface height anomaly SLA data provided by satellite altimeter, in the daily data snapshot, identify local maxima and local minima through 5x5 neighborhood search; Step S22, noise filtering for extreme points, including: removing noise interference through 3x3 neighborhood; verifying the effectiveness of the extreme point through 7x7 neighborhood; Step S23, taking the extreme point as the starting point, using the iterative threshold method to expand outward, the iteration step is 0.05 cm, calculate the closed loop contour, until the termination condition is met; Step S24, determine the vortex boundary by reverse rollback method; Step S25, retain the closed vortex structure with spatial resolution not less than 0.25°x0.25° and grid number≥4; In step S3, the main steps of vortex tracking are as follows: Step S31, based on the Rossby phase velocity theory, limit the search range of vortex propagation, and preferentially match the spatiotemporally nearest adjacent vortex to construct the trajectory; Step S32, through attribute consistency test to constrain the matching conditions of vortex at adjacent time t and t+1, including: the vortex area change amplitude is controlled within 0.25-2.75 times; the vortex amplitude change amplitude is controlled within 0.25-2.75 times; Step S33, for eddies with disappearance time less than 1 day, insert virtual vortex nodes to maintain the continuity of the trajectory, and calculate the virtual node position by linear extrapolation interpolation based on the historical propagation speed; Step S34, remove the virtual vortex nodes in the final trajectory data.

2. The method of claim 1, wherein, In step S1, the downloaded data range needs to be slightly larger than the estimated range in time and space scale, and the collected data needs to be preprocessed, and the data is interpolated to the standard layer in depth.

3. The method of mesoscale eddy energy conversion analysis according to claim 2, wherein, In step S23, the termination conditions include: new extreme points appear in the closed loop area; the iteration number of extreme points no longer increases; the closed loop contour cannot continue to expand.

4. The method of mesoscale eddy energy conversion analysis according to claim 3, wherein, In step S4, the calculation methods of vortex kinetic energy EKE and vortex effective potential energy EPE are as follows: Step S41, extract the zonal and meridional components of the horizontal flow field and and define the background field of the flow velocity components and the rate of change over the duration of the vortex , The original flow velocity is decomposed, and the calculation relationship of each parameter is as follows: ； ； wherein, is the rate of change of the zonal component of the flow velocity, is the zonal component of the background field flow velocity, is the rate of change of the meridional component of the flow velocity, is the meridional component of the background field flow velocity; Step S42, the calculation formula of vortex kinetic energy EKE is as follows: ； wherein, R is the reference density; Step S43, calculate seawater density based on seawater state equation UNESCO EOS-80 using seawater temperature, salinity, pressure data and the potential density of the background field The background density as a function of depth is obtained by spatially averaging over the study region and temporally averaging over the duration of the eddy, and the perturbation density is calculated, according to the formula: ； wherein, is the perturbation density, is the depth-dependent background density, is the longitude coordinate, is the latitude coordinate, is the depth at which, is the time; Step S44, the effective potential energy of each grid point in the vortex range is calculated, and the formula is as follows: ； where, is the gravitational constant, is the rate of change of the perturbed density, is the density, is the background field potential density.

5. The method of mesoscale eddy energy conversion analysis according to claim 4, wherein, In step S5, the baroclinic conversion term T2 is calculated according to the following formula: ； wherein is the background field perturbation density; The barotropic conversion term T4 is calculated according to the following formula: 。 6. The method of mesoscale eddy energy conversion analysis according to claim 5, wherein, In step S6, the kinetic energy budget equation is constructed, and the formula is as follows: ； wherein, represents the time rate of change of the kinetic energy of the vortex; ； ； ； ； ； wherein, is the vertical velocity change rate, is is the directional wind stress component change rate, is is the directional wind stress component change rate, is the sea water pressure change rate.

7. The method of mesoscale eddy energy conversion analysis according to claim 6, wherein, wind stress direction component and direction component The calculation formula is as follows: ； ； where, is the wind speed at sea level 10 m, , and are the wind speeds of the sea surface 10 m wind field direction and direction, respectively, is the drag coefficient, which is calculated as follows: 。 8. The method of mesoscale eddy energy conversion analysis according to claim 7, wherein, In step S7, the vortex time series of each term is calculated according to the following steps: Step S71, according to the vortex range of each time point obtained in step S3, the vortex grid point and the vortex grid point are determined; Step S72, selecting the depth within the vortex influence range, and performing depth integration at the vortex grid point; Step S73, spatially averaging the integration results of each time point vortex grid point to obtain the time series of each term.

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