CN-121981017-A - Ocean mesoscale vortex and near-inertial internal wave energy exchange analysis method

CN121981017ACN 121981017 ACN121981017 ACN 121981017ACN-121981017-A

Abstract

The invention discloses a marine mesoscale vortex and near-inertial internal wave energy exchange analysis method, which belongs to the technical field of marine dynamics and comprises the following steps of S1, determining a target mesoscale vortex area, acquiring high-resolution three-dimensional flow field data, preprocessing to obtain standardized three-dimensional flow field data, S2, extracting near-inertial flow components and background flow components through frequency domain filtering separation processing, S3, obtaining Reynolds stress components through sliding time average processing, S4, obtaining strain rate components in the horizontal direction through space derivative calculation and strain rate derivation processing, S5, substituting into an energy exchange equation to obtain energy exchange rate, S6, completing depth and time integration processing in combination with sea water density to obtain net energy exchange quantity and realizing discrimination of energy transfer directions. By adopting the method, the high-precision quantitative analysis and accurate judgment of the transfer direction of the ocean mesoscale vortex and near-inertial internal wave energy exchange direction and intensity are realized.

Inventors

HONG BO
CHEN JIAHAO

Assignees

华南理工大学

Dates

Publication Date: 20260505
Application Date: 20260403

Claims (8)

1. The ocean mesoscale vortex and near-inertial internal wave energy exchange analysis method is characterized by comprising the following steps of: S1, determining a target mesoscale vortex region based on satellite remote sensing and typhoon data, acquiring high-resolution three-dimensional flow field data covering the target mesoscale vortex region, and finishing data preprocessing to obtain standardized three-dimensional flow field data; S2, based on the standardized three-dimensional flow field data of the S1, the near-inertial flow component and the background flow component are respectively extracted through a band-pass filter by frequency domain filtering separation processing, and the near-inertial flow longitudinal/latitudinal flow velocity and the background flow longitudinal/latitudinal flow velocity are obtained; S3, obtaining a Reynolds stress component through sliding time average processing based on the near-inertial flow longitudinal/latitudinal flow velocity of the S2; S4, obtaining a horizontal strain rate component through spatial derivative calculation and strain rate deduction processing based on the background flow longitudinal/latitudinal flow velocity of the S2; S5, quantitatively calculating based on the Reynolds stress component of the S3 and the strain rate component of the horizontal direction of the S4 by substituting a preset energy exchange equation to obtain the energy exchange rate between the mesoscale vortex and the near-inertial flow; S6, based on the energy exchange rate of S5, integrating the depth and time by combining the sea water density, obtaining the net energy exchange quantity of the mesoscale vortex and the near-inertial internal wave and realizing the discrimination of the energy transfer direction.
2. The method for analyzing ocean mesoscale eddy and near-inertial internal wave energy exchange according to claim 1, wherein in S1, the spatio-temporal range of the high-resolution three-dimensional flow field data is set to be larger than that of the target mesoscale eddy region based on the spatio-temporal range characteristics of the target mesoscale eddy region, meanwhile, the high-resolution three-dimensional flow field data is interpolated to an ocean standard layer in the depth direction, and data standardization preprocessing is completed, so that standardized three-dimensional flow field data containing warp-wise and weft-wise flow velocity information is obtained.
3. The method for analyzing ocean mesoscale eddy and near inertial internal wave energy exchange of claim 2, wherein the high-resolution three-dimensional flow field data in S1 is satellite altimeter remote sensing data or ocean analysis data set or ocean site observation data.
4. A marine mesoscale eddy and near inertial internal wave energy exchange analysis method according to claim 3, wherein the specific step of S2 comprises: s21, based on the standardized three-dimensional flow field data of S1, extracting warp and weft original flow field data with the duration not less than thirty days, performing depth average on the original flow field data to obtain positive pressure flow velocity, and subtracting the corresponding positive pressure flow velocity from the original flow field data to obtain weft component of the oblique pressure flow velocity And warp component ; S22, center latitude based on target mesoscale vortex area Calculate the corresponding inertial frequency The calculation formula is as follows: ; Wherein, the Is the rotation angular velocity of the earth; s23, at the inertia frequency of S22 As core parameters, design passband frequency range as Bandwidth of Fourth order Butterworth band-pass filter; S24, the inclined pressure flow velocity of S21 、 A fourth order Butterworth band pass filter is input, filtering to obtain near-inertial flow direction component Sum weft component ; S25, presetting the low-pass filtering cut-off frequency as To bias flow rate 、 Inputting the background flow direction component into a fourth-order Butterworth band-pass filter again, and filtering to obtain the background flow direction component Sum weft component 。
5. The method for analyzing energy exchange between ocean mesoscale eddy and near inertial internal wave energy according to claim 4, wherein the specific step of S3 comprises the following steps: S31, near-inertial flow radial component based on S24 Sum weft component Calculating flow velocity square value and square value respectively, namely 、 And ; S32, inertial frequency based on S22 Calculating the inertia period The calculation formula is as follows: ; and determining a moving average window covering 3 near inertia periods as ; S33, will S31 、 And According to window length Performing time-moving average treatment to obtain Reynolds stress component , And 。
6. The method for analyzing energy exchange between marine mesoscale eddy and near inertial internal wave energy according to claim 5, wherein the step S4 comprises the following steps: S41, longitude based on target mesoscale vortex area And latitude of Converting the longitude and latitude grid spacing of the flow field data into metric actual distance, wherein the calculation formula is as follows: ; ; Wherein the method comprises the steps of Is the longitude difference; is the latitude difference value; 、 Longitude and latitude; S42, flowing the background flow of S25 to the component Sum weft component And the metric actual distance of S41 And The spatial partial derivative is obtained through the second-order center difference format calculation, and the calculation formula is as follows: ; ; ; ; Wherein, the As background flow latitudinal component First order partial derivative in x-direction; As background flow latitudinal component First partial derivative in y direction; For background flow direction component First order partial derivative in x-direction; For background flow direction component First partial derivative in y direction; S43, spatial partial derivative obtained based on S42 、、、 Calculating the normal strain rate component in the horizontal direction And tangential strain rate component The calculation formula is as follows: ; 。
7. The method for analyzing energy exchange between ocean mesoscale eddy and near inertial internal wave energy according to claim 6, wherein the specific step of S5 comprises the following steps: S51, the Reynolds stress component of step S33 , 、 And a strain rate component of S43 、 As equation input parameters, an energy exchange equation is constructed, and the equation formula is as follows: ; Wherein, the Is the energy exchange rate; s52, substituting the input parameters into the energy exchange equation of S51 to perform point-by-point and time-by-time calculation to obtain the output parameter energy exchange rate Energy exchange rate Is a physical quantity that varies with space, time, and depth.
8. The method for analyzing energy exchange between ocean mesoscale eddy and near inertial internal wave energy according to claim 7, wherein the step S6 comprises the following steps: s61, collecting seawater temperature, salinity and pressure data of a target mesoscale vortex area, inputting the seawater temperature, salinity and pressure data into a seawater state equation UNESCOEOS-80, and calculating to obtain the seawater density which changes along with space, time and depth ; S62, determining the influence depth range of the target mesoscale vortex And time range And based on the energy exchange rate of S52 Density of sea water with S61 And performing depth integration and time integration, wherein the formula is as follows: ; Wherein, the Is the net energy exchange rate; for a period of time of Depth and depth of Specific magnitude of in-range mesoscale eddy and near-inertial internal wave energy exchange; s63, according to net energy exchange amount The positive and negative values of (a) determine the energy transfer direction when When positive, energy is transferred from the medium-scale vortex to near-inertial internal wave, when At negative values, energy is transferred from the near-inertial internal wave to the mesoscale vortex.

Description

Ocean mesoscale vortex and near-inertial internal wave energy exchange analysis method Technical Field The invention relates to the technical field of ocean dynamics, in particular to a method for analyzing energy exchange of ocean mesoscale vortex and near-inertial internal wave energy. Background The energy exchange between the mesoscale vortex and the near-inertial internal wave is a core mechanism of ocean energy cascade, has decisive significance for driving ocean turbulence mixing, maintaining a circulation structure and regulating and controlling a global climate system, is based on satellite remote sensing, field observation or ocean re-analysis of flow field data, adopts frequency domain filtering to separate flow field components, kinetic energy difference estimation and other means, tries to analyze the energy transfer relationship between the mesoscale vortex and the near-inertial internal wave, and is mainly used for relevant scenes such as ocean circulation simulation, turbulent mixing mechanism research, global climate system regulation and control law analysis and the like. The quantitative description of Reynolds stress and background flow strain rate coupling mechanism is generally lacking in the process of quantifying medium-scale vortex and near-inertia internal wave energy exchange, and the method has the defects that firstly, the traditional method estimates energy exchange only through a kinetic energy difference value, dynamic regulation and control action of a strain field is completely ignored, the adopted simplified calculation formula cannot capture the modulation action of anisotropy of near-inertia internal wave velocity fluctuation on energy transfer, the energy exchange intensity of a vortex normal strain leading region is overestimated by more than 20%, the energy exchange rate calculation has obvious systematic deviation, secondly, the judgment is carried out only by depending on the sign of energy change in the energy transfer direction, the misjudgment of the vortex-wave energy transfer direction is easy to occur, the misjudgment of the ocean energy transfer direction is directly caused, the serious distortion occurs in ocean energy balance analysis, the parameterization precision of ocean loop model energy input is severely restricted, and the accurate and reliable quantitative support technology cannot be provided for multi-scale energy interaction research. Disclosure of Invention The invention aims to provide a marine mesoscale vortex and near-inertial internal wave energy exchange analysis method, which solves the technical problems. In order to achieve the above purpose, the invention provides a marine mesoscale vortex and near-inertial internal wave energy exchange analysis method, which comprises the following steps: S1, determining a target mesoscale vortex region based on satellite remote sensing and typhoon data, acquiring high-resolution three-dimensional flow field data covering the target mesoscale vortex region, and finishing data preprocessing to obtain standardized three-dimensional flow field data; S2, based on the standardized three-dimensional flow field data of the S1, the near-inertial flow component and the background flow component are respectively extracted through a band-pass filter by frequency domain filtering separation processing, and the near-inertial flow longitudinal/latitudinal flow velocity and the background flow longitudinal/latitudinal flow velocity are obtained; S3, obtaining a Reynolds stress component through sliding time average processing based on the near-inertial flow longitudinal/latitudinal flow velocity of the S2; S4, obtaining a horizontal strain rate component through spatial derivative calculation and strain rate deduction processing based on the background flow longitudinal/latitudinal flow velocity of the S2; S5, quantitatively calculating based on the Reynolds stress component of the S3 and the strain rate component of the horizontal direction of the S4 by substituting a preset energy exchange equation to obtain the energy exchange rate between the mesoscale vortex and the near-inertial flow; S6, based on the energy exchange rate of S5, integrating the depth and time by combining the sea water density, obtaining the net energy exchange quantity of the mesoscale vortex and the near-inertial internal wave and realizing the discrimination of the energy transfer direction. Preferably, in the step S1, based on the space-time range characteristics of the target mesoscale vortex region, the space-time range of the high-resolution three-dimensional flow field data is set to be larger than that of the target mesoscale vortex region, and meanwhile, the high-resolution three-dimensional flow field data is interpolated to the ocean standard layer in the depth direction, so that the data standardization preprocessing is completed, and the standardized three-dimensional flow field data containing warp-wise and weft-wise flow velocit