A method for determining dynamic flooding information based on overflow and wave cresting

Abstract

The present invention relates to a method for determining dynamic inundation information based on overflow and wave cresting, and relates to the fields of marine disaster prediction and coastal protection engineering technology. The method comprises: constructing an atmosphere-ocean circulation-wave coupling model to divide a target area into target grids corresponding to ocean circulation patterns, wave patterns, and atmospheric numerical models, with coastal protection structures located within the target area; determining hydrodynamic data and wave element data based on the atmosphere-ocean circulation-wave coupling model; dividing the coastal protection structures in the target area into multiple calculation units; and determining the total amount of inundation behind the coastal protection structures within each calculation unit based on the hydrodynamic data, wave element data, and a dynamically coupled calculation model of the constructed coastal protection structure overflow and wave cresting model, thereby generating dynamic inundation information for the target area. This method reflects the total inundation caused by the synergistic effect of overflow and wave cresting in real time, improving the calculation accuracy of inundation within the composite coastal protection structure.

Description

Technical Field

[0001] The present invention relates to the technical field of marine disaster prediction and coastal protection engineering, and in particular to a method for determining dynamic submergence information based on overflow and wave cresting. Background Art

[0002] As climate change intensifies, extreme weather events are becoming more frequent in coastal areas. Even with good protection, coastal areas continue to suffer from flooding due to the functional and structural failure of natural barriers and coastal defenses. Research shows that the combined effects of overflow from coastal protection structures and wave overtopping are the primary causes of coastal flooding. Especially under extreme weather conditions, waves can contribute over 40% of total inundation.

[0003] Traditional coastal flood risk assessment relies on storm surge-wave coupling models, but these models struggle to accurately calculate overflows from coastal protection structures. Phase-averaged wave models like SWAN (Simulation Wave Nearshore) also fail to characterize wave cresting mechanisms and accurately simulate wave reflection and breaking processes. Emerging flood risk assessment methods, while considering both overflows and wave crests, employ step-by-step calculations and simple superposition, ignoring their nonlinear interactions and inadequately accounting for the effects of oblique waves. Summary of the Invention

[0004] In order to overcome the problems existing in the related art, the present invention provides a method for determining dynamic submergence information based on overflow and wave top.

[0005] According to an embodiment of the present invention, a method for determining dynamic submergence information based on overflow and wave top is provided, the method comprising:

[0006] Constructing an atmosphere-ocean circulation-wave coupling model to divide a target area into target grids corresponding to three preset modes, wherein the three preset modes include an ocean circulation mode, an ocean wave mode, and an atmospheric numerical mode, and wherein a coastal protection structure is installed within the target area;

[0007] Determining hydrodynamic data under the ocean circulation model and wave element data under the ocean wave model based on the atmosphere-ocean circulation-wave coupling model;

[0008] dividing the coastal protection structure of the target area into a plurality of calculation units;

[0009] Determine the total amount of inundation behind the coastal protection structure in each calculation unit based on the hydrodynamic data, the wave element data, and a dynamically coupled calculation model of the coastal protection structure overflow and wave overtopping model;

[0010] Based on the total flooding amount, dynamic flooding information of the target area is generated. In some embodiments of the present invention, the construction of the atmosphere-ocean circulation-wave coupling model includes:

[0011] Dividing the target area into target grids corresponding to the three preset modes one by one;

[0012] Acquiring water depth and topographic data required by each target grid, the water depth and topographic data including water depth data required by the ocean circulation model, water depth data required by the wave model, and terrain elevation and land use type required by the atmospheric numerical model;

[0013] Obtaining the initial time data, full-time boundary grid data and control equations of each preset mode respectively;

[0014] The initial moment data and the full-time boundary grid data are interpolated into the corresponding target grid, respectively, so that the initial moment data and the full-time boundary grid data serve as the initial conditions and boundary conditions of the target grid. In some embodiments of the present invention, determining the hydrodynamic data in the ocean circulation model and the wave element data in the wave model based on the atmosphere-ocean circulation-wave coupling model includes:

[0015] Based on the water depth topography data, the initial time data and the boundary grid data at all times, respectively solving the control equations corresponding to each preset mode by the finite difference method according to a preset time step, and obtaining the physical field corresponding to each preset mode at each coupling time;

[0016] Transmitting the physical field corresponding to each of the preset modes through a data coupler;

[0017] The data coupler automatically routes the obtained physical field and differs the physical field corresponding to each preset mode into the corresponding target grid to obtain mapped field variables, which include the hydrodynamic data and the wave element data.

[0018] In some embodiments of the present invention, the hydrodynamic data includes the static water level in front of the coastal protection structure in each of the calculation units, and the wave element data includes the wavelength, effective wave height and wave direction of the waves in front of the coastal protection structure in each of the calculation units.

[0019] In some embodiments of the present invention, dividing the coastal protection structure of the target area into a plurality of calculation units includes:

[0020] Based on the target grid, the coastal protection structure of the target area is divided into a plurality of calculation units.

[0021] In some embodiments of the present invention,

[0022] The dynamic coupling calculation model based on the hydrodynamic data, the wave element data and the constructed coastal protection structure overflow and wave overtopping model, determining the total amount of inundation behind the coastal protection structure in each calculation unit includes:

[0023] Determining the top elevation of the coastal protection structure in the target area;

[0024] Determining the top elevation of the coastal protection structure in each of the calculation units based on the top elevation of the coastal protection structure in the target area;

[0025] determining a unit overflow of the coastal protection structure per unit length in each calculation unit based on the top elevation of the coastal protection structure in each calculation unit and the hydrodynamic data;

[0026] Based on the top elevation of the coastal protection structure in each calculation unit and the wave element data, obtaining the unit wave height of the coastal protection structure within a unit length;

[0027] Based on the unit overflow and the unit wave top elevation, the total amount of inundation behind the coastal protection structure in each calculation unit is obtained. In some embodiments of the present invention, the unit overflow of the coastal protection structure per unit length in each calculation unit is determined based on the top elevation of the coastal protection structure in each calculation unit and the hydrodynamic data, using the formula:

[0028] ,

[0029] in, is the overflow of the coastal protection structure in each calculation unit, g is the acceleration of gravity, It is the distance between the still water level in front of the coastal protection structure in each calculation unit and the top elevation of the coastal protection structure in each calculation unit.

[0030] In some embodiments of the present invention, the unit wave top elevation of the coastal protection structure within a unit length is obtained based on the top elevation of the coastal protection structure and the wave element data in each calculation unit, and the formula used is:

[0031]

[0032] in, is the wave crest value of the coastal protection structure in each calculation unit, , is the slope in front of the coastal protection structure in each calculation unit, and is Determine the non-dimensional factor, where:

[0033]

[0034] is the maximum wave run-up height in front of the coastal protection structure in each calculation unit, The undetermined unbroken significant wave height in front of the coastal protection structure within each calculation unit.

[0035] In some embodiments of the present invention, the step of obtaining the total amount of inundation behind the coastal protection structure in each calculation unit based on the unit overflow volume and the unit wave overtopping volume includes:

[0036] The unit overflow volume and the unit wave overtopping volume are superimposed according to the combination methods corresponding to different flooding scenarios to obtain the total flooding volume behind the coastal protection structure within a unit length;

[0037] determining the length of the coastal protection structure within each of the calculation units based on the target grid;

[0038] The total flooding volume behind the coastal protection structure within the unit length is multiplied by the length of the coastal protection structure within each calculation unit to obtain the total flooding volume behind the coastal protection structure within each calculation unit.

[0039] In some embodiments of the present invention, after determining the total amount of inundation behind the coastal protection structure in each calculation unit based on the hydrodynamic data and the constructed dynamic coupling calculation model of the coastal protection structure overflow, the wave element data, and the coastal protection structure wave crest, the step further includes:

[0040] The total amount of inundation behind the coastal protection structure in each calculation unit is added as a mass source and sink term to the calculation corresponding to the ocean circulation model in the atmosphere-ocean circulation-wave coupling model to correct the real-time hydrodynamic data of the target area;

[0041] The step of generating dynamic flooding information of the target area based on the total flooding amount includes:

[0042] Preprocessing digital elevation model data to obtain corrected digital elevation model data;

[0043] Determining the real-time water level elevation of the target area based on the total amount of inundation;

[0044] Based on the corrected digital elevation model data and the real-time water level elevation, calculating the inundation range and inundation depth distribution of the target area in each time period according to a preset time step;

[0045] Dynamic flooding information of the target area is generated based on the flooding range and flooding depth distribution of the target area in each time period.

[0046] The technical solutions provided by the embodiments of the present invention may have the following beneficial effects:

[0047] The method for determining dynamic inundation information based on overflow and wave cresting disclosed in the present invention avoids the defects of traditional single models ignoring wave effects or wave models lacking meteorological driving through the atmosphere-ocean circulation-wave coupling model. At the same time, through the corresponding combination methods under multiple inundation scenarios, the superposition of the calculation results of the coastal protection structure overflow and wave cresting models is made more reliable. Through the dynamic coupling calculation model of the coastal protection structure overflow and wave cresting models, the total inundation behind the coastal protection structure is dynamically calculated, reflecting the synergistic effect of overflow and wave cresting in real time. At the same time, dynamic inundation information of the target area is generated in real time based on the total inundation amount, which is beneficial to the composite flood risk assessment behind the coastal protection structure under extreme meteorological conditions, the optimized design of the coastal protection structure, and the construction of the urban flood prevention and early warning system. It solves the problem that the traditional phase-averaged wave numerical model fails in evaluating the wave crest of the coastal protection structure and the technical defect that the traditional coastal protection structure rear inundation calculation method does not consider dynamic wave conditions, oblique waves and composite inundation processes, and significantly improves the calculation accuracy of inundation within the composite coastal protection structure.

[0048] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0050] Figure 1 is a flow chart illustrating a method for determining dynamic submergence information based on overflow and wave top according to an embodiment;

[0051] Figure 2 is a schematic diagram illustrating various scenarios of flooding of a coastal area protected by a coastal protection structure according to an embodiment;

[0052] Figure 3 is a schematic diagram showing a design of an average grid scheme for calculating the oblique wave direction in front of a coastal protection structure according to an embodiment;

[0053] Figure 4 is a schematic diagram showing the scope of the target area and terrain according to an embodiment;

[0054] Figure 5is a schematic diagram of a water level duration curve of a target area according to an embodiment;

[0055] Figure 6 is a schematic diagram showing the flooding range behind a coastal protection structure at a representative moment according to an embodiment;

[0056] Figure 7 FIG. 1 is a flood risk map behind a coastal protection structure at a representative moment according to an embodiment. DETAILED DESCRIPTION

[0057] Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, identical numerals in different drawings represent identical or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present invention, as detailed in the appended claims.

[0058] As climate change intensifies, extreme weather events are becoming more frequent in China's coastal areas. Even well-protected coastal areas have suffered varying degrees of flooding due to functional and structural failures of natural barriers or coastal defenses. Numerous studies have shown that flooding in coastal areas protected by coastal protection structures is often caused by a combination of overflow from these structures and wave overtopping. In storm surge flooding events in low-lying coastal areas, especially under extreme meteorological conditions, waves can contribute over 40% of the total inundation. Therefore, wave-induced flooding, such as wave overtopping caused by wave run-up, is increasingly becoming a major cause of coastal inundation in low-lying coastal areas. The accuracy of risk assessments directly impacts the reliability of coastal protection projects and urban flood control safety.

[0059] Traditional coastal flood risk assessment methods rely on storm surge-wave coupled numerical models to provide water level and inundation data at the boundaries of the inundation zone. However, in traditional wave-current coupled models, the overflow of coastal protection structures caused by storm surges cannot be accurately calculated due to the limitations of model accuracy. At the same time, wave models such as SWAN, as a phase-averaged wave model, cannot characterize the wave topping mechanism of coastal protection structures under existing water depth and terrain conditions, and it is also difficult to accurately simulate the front reflection and wave breaking process of coastal protection structures.

[0060] In recent years, emerging flood risk assessment methods have begun to consider both coastal protection structure overflow and wave crest. However, these methods typically calculate coastal protection structure overflow and wave crest separately, using a step-by-step model to estimate their respective contributions, and then simply superimposing them to obtain the total inundation. However, this approach ignores the nonlinear interaction between coastal protection structure overflow and wave crest. Furthermore, when considering the influence of oblique waves on the wave crest model, simply specifying a wave parameter in front of the coastal protection structure as the input for the oblique wave correction coefficient can lead to significant deficiencies.

[0061] An exemplary embodiment of the present invention provides a method for determining dynamic flooding information based on overflow and wave top, such as Figure 1 As shown, the method includes:

[0062] S100: Construct an atmosphere-ocean circulation-wave coupling model to divide the target area into target grids corresponding to three preset modes, wherein the three preset modes include an ocean circulation model, a wave model, and an atmospheric numerical model, and a coastal protection structure is set in the target area.

[0063] For example, when constructing an atmosphere-ocean circulation-wave coupling model, the target area must be determined first, where the shape of the target area can be, for example, Figure 4 The fan-shaped image shown in the figure collects the water depth and topographic data of the target area. It can be understood that the water depth and topographic data of the target area can be the water depth data of the ocean and coastal areas in the target area, the elevation data of the land surface and the land use data, such as the coastal zone topography, the land topography near the coastal protection structure, etc. According to the characteristics of the target area, the ocean circulation model, the wave model, and the atmospheric numerical model are divided, and then the target grids corresponding to the three preset models are made, and then the control equation group corresponding to each preset model is determined, so that the control equation group can be used to calculate the hydrodynamic data under the preset mode of the ocean circulation model and the wave element data under the wave model, etc.

[0064] S200: Determine the hydrodynamic data of the ocean circulation model preset mode and the wave element data of the ocean wave model based on the atmosphere-ocean circulation-wave coupling model.

[0065] For example, the CFL criterion (Courant-Friedrichs-Lewy criterion) can be used to ensure the stability of the numerical solution and determine the time step for each model to run independently and the time step for exchanging time data between the three models. The CFL criterion is a necessary condition for determining whether the time step is stable. Hydrodynamic data includes, but is not limited to, data related to ocean circulation models, such as sea surface water level (still water level, storm surge level), current velocity, and seawater temperature. Wave element data includes, but is not limited to, data related to ocean wave models, such as wave height (wave height), the time interval between adjacent waves passing through a fixed point (wave period), the direction of wave propagation (wave direction), and the horizontal distance between adjacent wave crests (wavelength). In addition, to make the results more accurate, atmospheric numerical model data, such as wind speed, wind direction, and sea surface pressure, can also be calculated using the atmosphere-ocean circulation-wave coupling model. Exemplarily, the MCT coupler exchanges data in real time between the three modes according to the data exchange time step. According to the preset mode, the atmospheric numerical model provides meteorological data such as wind speed at a height of 10m, temperature at a height of 2m, and surface air pressure to the ocean circulation model and the wave model. The ocean circulation model provides flow velocity, water depth and sea surface water level data to the atmospheric numerical model and the wave model. The wave mode provides wave elements such as wave height, wavelength, wave direction, and wave period to the atmospheric numerical model and the ocean circulation model.

[0066] S300: Divide the coastal protection structure of the target area into multiple calculation units.

[0067] Exemplarily, the coastal protection structures in the target area are divided into a plurality of calculation units according to at least one of the target grids in one-to-one correspondence with the three preset modes.

[0068] S400: Determine the total amount of inundation behind the coastal protection structure in each calculation unit based on the dynamic coupling calculation model of hydrodynamic data, wave element data and the constructed coastal protection structure overflow and wave overtopping model.

[0069] Exemplarily, the total inundation volume in each calculation unit is calculated separately, wherein the total inundation volume includes overflow volume and wave crest volume. The overflow volume is obtained by providing the sea surface water level in real time through the ocean circulation model. Based on the sea surface water level, the overflow volume of the coastal protection structure per unit length is calculated using the weir flow formula of the wide-top structure. The wave crest volume is obtained by providing the wavelength and wave height in real time through the wave model. Based on the wavelength and wave height, the wave crest volume of the coastal protection structure per unit length is calculated using the wave crest formula. By calculating the overflow volume of the coastal protection structure per unit length and the wave crest volume of the coastal protection structure per unit length in real time, and according to the combination method corresponding to various inundation scenarios, the total inundation volume behind the coastal protection structure in each calculation unit is obtained, thereby dynamically calculating the dynamic inundation conditions along the coast under the influence of the overflow of the coastal protection structure and the wave crest of the coastal protection structure.

[0070] S500: Generate dynamic flooding information of the target area based on the total amount of flooding.

[0071] In this embodiment, the total amount of inundation behind the coastal protection structure in each calculation unit is multiplied by the length of the coastal protection structure in the target area to obtain the total amount of inundation in the entire target area. The total amount of inundation behind the coastal protection structure is dynamically calculated according to the set time step, and then the dynamic inundation information of the target area is generated.

[0072] In this embodiment, the atmosphere-ocean circulation-wave coupling model is used to avoid the defects of traditional single models that ignore wave effects or wave models that lack meteorological driving. At the same time, through the corresponding combination methods under various flooding scenarios, the superposition of the calculation results of the dynamic coupling calculation model of coastal protection structure overflow and wave crest is made more reliable. The total inundation behind the coastal protection structure dynamically calculated by the model reflects the synergistic effect of overflow and wave crest in real time. At the same time, dynamic inundation information of the target area is generated in real time based on the total inundation amount, which is beneficial to the composite flood risk assessment behind the coastal protection structure under extreme meteorological conditions, the optimal design of coastal protection structures, and the construction of urban flood prevention and warning systems. It solves the problem that the traditional phase-averaged wave numerical model fails in assessing the wave crest of the coastal protection structure and the technical defects of the traditional coastal protection structure rear inundation calculation method that does not take into account dynamic wave conditions, oblique waves, and composite inundation processes. It significantly improves the calculation accuracy of inundation within the composite coastal protection structure.

[0073] In one embodiment, Figure 1 As shown, in step S100, constructing the atmosphere-ocean circulation-wave coupling model includes:

[0074] S101: Divide the target area into target grids corresponding to three preset modes.

[0075] Exemplarily, dividing the target area into target grids corresponding to the three preset modes includes determining the spatial size of the target area. It is understandable that the geometric range and grid division parameters of the target area are determined, such as the length, width, number of grids, grid inclination angle and other parameters of the target area. The target grids corresponding to each preset mode are divided, and the target grids include the target grid of the ocean circulation mode, the target grid of the wave mode and the target grid of the atmospheric value. It should be noted that all target grids are orthogonal grids. Among them, the calculation range of the target grid of the ocean circulation mode and the target grid of the wave mode can be the same or different. In this embodiment, the calculation range of the target grid of the ocean circulation mode and the target grid of the wave mode are the same, and the calculation range is 600. 600m, divided by 9.5° clockwise with due east as the reference.

[0076] Furthermore, the target grid for the OCM is a 15-layer structure with top and bottom densities, balancing the simulation requirements of surface dynamics, mid-layer temperature and salinity, and deep-layer flows. By dividing the ocean vertically (depthwise) into multiple layers, the model calculates parameters such as currents, temperature, and salinity for each layer separately, avoiding errors caused by "single-layer models" that ignore vertical differences. By densifying the top and bottom layers, the model achieves high-precision simulations in key areas with fewer computing resources, improving its responsiveness to extreme weather (such as typhoons) and complex terrain (such as narrow terrain).

[0077] The target grid of the atmospheric numerical model adopts a triple nested grid with a resolution of 15000 15000m first layer grid, 5000 5000m second layer grid and 1670 The third-layer grid of 1670m, the target grid of the atmospheric numerical model, can cover the entire target area and the nearby sea area, providing more accurate data support for the wind field data required by the ocean circulation model and wave model. Through the triple nested grid, the wind field accuracy of the target area is guaranteed.

[0078] The target area is divided into target grids corresponding to the ocean circulation model, wave model, and atmospheric numerical model. When using the control equation group to calculate the ocean circulation model, wave model, and atmospheric numerical model, each model has different requirements for terrain data. The target area needs to be divided into target grids corresponding to the three preset models to improve calculation efficiency and accuracy and avoid loading redundant data for each model. For example, the ocean model does not require the height of urban buildings, which reduces the consumption of computing resources.

[0079] S102: Acquire water depth and topographic data required for each target grid. The water depth and topographic data include water depth data required for an ocean circulation model, water depth data required for an ocean wave model, and topographic elevation and land use type required for an atmospheric numerical model.

[0080] For example, referring to Figure 4 , collect the required water depth and topography data for each target grid within the target area. It is understood that the water depth and topography data of the target area can include water depth data of the ocean and coastal areas within the target area, and elevation data of the land surface, such as coastal topography and landforms near coastal protection structures. The water depth and topography data of the target area can be obtained using methods such as nautical chart mapping, satellite remote sensing, aerial photogrammetry, or ground survey.

[0081] Among them, obtain the measured nautical chart data of the open sea area around the target area, refer to Figure 4 , ensuring the terrain accuracy of the constructed atmosphere-ocean circulation-wave coupling model in the target area and improving the accuracy of hydrodynamic calculations near coastal protection structures.

[0082] Acquire global bathymetry and topography data with a 15 arc-second resolution (SRTM15+) to provide bathymetry background outside the target area (such as offshore topography) and ensure reasonable water depths at the open boundaries of ocean circulation models and wave models.

[0083] Based on measured nautical chart data and global water depth and topography data, cubic spline interpolation is performed on the initial grids of the ocean circulation model and the wave model. The resulting high-precision water depth and topography data are used to generate the water depth and topography conditions for the ocean circulation model and the wave model. It should be noted that spline interpolation is a mathematical method that fits a smooth curve (spline function) to fill discrete topography data (such as measured points on a nautical chart) into a regular grid, so that each grid point has a corresponding water depth / topography value. In this way, irregularly distributed measured data or low-resolution data are converted into high-precision data that fully matches the grid required by the atmosphere-ocean circulation-wave coupling model.

[0084] Obtain static geographic data required for atmospheric numerical model processing through open datasets. Static geographic processing data includes, but is not limited to, terrain elevation data, land surface elevations within the target area (e.g., elevations of mountains, hills, and plains), land use type data, land cover types (e.g., urban, forest, farmland, ocean, etc.), and surface roughness parameters.

[0085] The obtained static geographic data required for atmospheric numerical model processing is spline interpolated into the atmospheric numerical model grid to obtain more accurate atmospheric numerical model grid terrain conditions.

[0086] S103 , respectively obtaining the initial time data, full-time boundary grid data, and control equation group of each preset mode.

[0087] Exemplarily, the initial time data and all-time boundary grid data required for the atmosphere-ocean circulation-wave coupled model are generated based on the target grids corresponding to the three models. For example, water level, temperature-salinity, and current velocity data that meet the temporal and spatial scope of the target region are downloaded from the Global Ocean Circulation Dataset and used as the initial time data and all-time boundary grid data for the target grid of the ocean circulation model. Wave element data such as wave height, wave period, and wave direction that meet the temporal and spatial scope of the target region are downloaded from the Global Ocean Wave Forecast Historical Reanalysis Dataset and used as the initial time data and all-time boundary grid data for the target grid of the wave model. Single pressure data (single pressure data refers to data on a single pressure layer, typically meteorological parameters for a specific pressure altitude layer (e.g., 1000 hPa, 850 hPa, etc.), including wind speed, wind direction, temperature, and humidity at that layer) and pressure data (pressure data refers to surface pressure data, i.e., the pressure value near the ground (sea level) (e.g., standard atmospheric pressure, approximately 1013 hPa)) are obtained from the fifth-generation reanalysis product of the European Centre for Medium-Range Weather Forecasts. The acquired single pressure data and pressure data are used as the initial time data of the target grid and the full-time boundary grid data of the atmospheric numerical model.

[0088] The ocean circulation model uses the Reynolds-averaged Navier-Stokes (NS) governing equations:

[0089] The equation of motion in the horizontal direction is:

[0090]

[0091]

[0092] in, is the velocity vector of Directional component, are Cartesian horizontal and vertical coordinates, is the Coriolis force parameter, For time, is the dynamic pressure, is the forcing / source term, is an optional horizontal diffusion item, horizontal speed u The turbulent pulsation component of horizontal speed v The turbulent pulsation component of Vertical speed w The turbulent pulsation component of is the forcing / source term of horizontal motion, is an optional horizontal diffusion item.

[0093] The equation of motion in the vertical direction is:

[0094]

[0095] in, is the acceleration due to gravity, is the local density, is the density of seawater.

[0096] The continuity equation is:

[0097]

[0098] The scalar transport equation is:

[0099]

[0100] in, is a scalar quantity, such as temperature, salinity, etc. is an optional horizontal diffusion item, is the forcing / source term, is the molecular viscosity coefficient and dissipation coefficient, is a scalar turbulent pulsation component, such as temperature, salinity, etc.

[0101] The state equation is:

[0102]

[0103] in, is the local density, is salinity, is the potential temperature, is the total pressure.

[0104] The ocean wave pattern is represented by a two-dimensional dynamic spectrum density representing random waves, i.e. ,in is the dynamic spectral density, is the energy spectrum density. The energy balance equation can be expressed in the spherical coordinate system as follows:

[0105]

[0106] in, is the action density, For time, is the direction of wave propagation, is the relative frequency, is the propagation speed of the action in geographic space and spectral space, are Cartesian horizontal and vertical coordinates, is the source-sink term.

[0107] The governing equation used in the atmospheric numerical model is:

[0108] The horizontal x-direction movement is:

[0109]

[0110] in, are the wind speed components in the east-west, north-south and vertical directions, is the Coriolis force parameter, is the modified Coriolis parameter, For time, is the atmospheric density, is the source term in the momentum equation, which represents the forcing effect on the east-west wind field. are Cartesian horizontal and vertical coordinates, is the air pressure term.

[0111] The horizontal y-direction movement is:

[0112]

[0113] in, is the source term in the momentum equation, which represents the forcing effect on the north-south wind field.

[0114] The vertical z-direction motion is:

[0115]

[0116] The thermodynamic equation is:

[0117]

[0118] in, is the temperature, is the constant pressure specific heat capacity of dry air, is the turbulent heat flux, For height.

[0119] The water vapor balance equation is:

[0120]

[0121] in, is the contribution of other physical processes such as turbulent diffusion and sub-grid scale processes to water vapor variation, is the water vapor source and sink term.

[0122] The continuity equation is:

[0123]

[0124] By solving the governing equations of atmospheric numerical models, it is possible to simulate the spatiotemporal distribution of meteorological elements such as wind speed, air pressure, and temperature, which drive ocean and wave motion. The governing equations of ocean circulation models can be used to calculate ocean dynamic parameters such as water level, current velocity, and temperature and salinity, thereby reflecting processes such as tides and storm surges. The wave model utilizes the wave energy balance equation to simulate phenomena such as wave height, wave period, and wave breaking, capturing the process from wave generation to nearshore propagation. Through the parallel computation of the governing equations and real-time data exchange, multi-modal coupling and interaction are achieved.

[0125] S104 , interpolating the initial moment data and the boundary grid data of all moments into the corresponding target grid respectively, so that the initial moment data and the boundary grid data of all moments serve as the initial conditions and boundary conditions of the target grid.

[0126] For example, water level, temperature, salinity, and current velocity data that meet the time and spatial scope of the target region are downloaded from the global ocean circulation dataset and used as the initial moment data and all-time boundary grid data for the target grid of the ocean circulation model. These data are then interpolated into the target grid of the ocean circulation model. Bilinear interpolation or cubic spline interpolation can be used for interpolation. Based on the model's runtime, the initial moment data and all-time boundary grid data interpolated into the target grid of the ocean circulation model are used as the model's initial and boundary conditions. Wave element data such as wave height, wave period, and wave direction that meet the time and spatial scope of the target region are downloaded from the global ocean wave forecast historical reanalysis dataset and used as the initial moment data and all-time boundary grid data for the target grid of the ocean wave model. These data are then interpolated into the target grid of the ocean wave model. Bilinear interpolation or cubic spline interpolation can be used for interpolation. Based on the model's runtime, the initial state of the data interpolated into the target grid of the ocean wave model and the all-time boundary grid data are used as the model's initial and boundary conditions. Single-level data (single-level data refers to data from a single pressure layer, typically a two-dimensional layer of variables near the surface, including wind speed, wind direction, temperature, humidity, etc.) and pressure level data (pressure level data refers to three-dimensional variables at multiple standard pressure altitudes in the atmosphere) are obtained from the European Centre for Medium-Range Weather Forecasts' fifth-generation reanalysis products. These data are used as the initial time data and all-time boundary grid data for the target grid of the atmospheric numerical model. These data are then interpolated into the target grid of the atmospheric numerical model using bilinear interpolation or cubic spline interpolation. The initial and boundary files required for the atmospheric numerical model are generated based on the temporal changes in the initial time data and all-time boundary grid data.

[0127] In this way, global measured data are used as the initial conditions and boundary conditions of the model to avoid the deviation between purely theoretical assumptions and the actual ocean state. The temporal changes in boundary conditions enable the model to simulate real ocean dynamic processes, such as the superimposed effect of "tide + storm surge" during typhoons. The output of the ocean circulation model (such as water level and flow rate) is fed back to the wave model and the atmospheric numerical model as boundary conditions. At the same time, the wave calculation results of the wave model can be used as wave-current coupling to improve the calculation accuracy of the ocean circulation model, forming a closed loop of coupled calculations, mutual verification of data, and reducing the risk of error accumulation in a single model.

[0128] In one embodiment, in step S200, determining the hydrodynamic data in the preset ocean circulation mode and the wave element data in the ocean wave mode based on the atmosphere-ocean circulation-wave coupled model includes:

[0129] S201. Based on the water depth topography data, the initial time data and the boundary grid data at all times, the control equations corresponding to each preset mode are solved by the finite difference method according to the preset time step to obtain the physical field corresponding to each preset mode at each coupling time.

[0130] According to the CFL criterion, the time step for each model to run independently and the time step for data exchange between the three models are determined. For example, the time step for the ocean circulation model is determined to be 60 seconds, the time step for the wave model is determined to be 300 seconds, and the time step for the atmospheric numerical model is determined to be 60 seconds. Data is exchanged between the three models every 1800 seconds. At each coupling moment, each preset model sends the prepared physical field (such as water level, wind stress, wave height, etc.) through the data coupler after its own calculation. For example, the atmospheric numerical model provides meteorological data such as wind speed at a height of 10 meters, temperature at a height of 2 meters, and sea surface pressure to the ocean circulation model and the wave model. The ocean circulation model provides flow velocity, water depth, and sea surface water level data to the atmospheric numerical model and the wave model. The wave model provides wave elements such as effective wave height, wavelength, and wave period to the atmospheric numerical model and the ocean circulation model.

[0131] After determining the time step for each mode to run independently and the time step for data exchange between the three modes, it also includes:

[0132] The three models define the physical factors to be considered. For example, based on actual simulation cases, the ocean circulation model defines the tidal scheme, turbulence closure scheme, air-sea interaction scheme, and bottom friction scheme. The wave model defines the wave spectrum, wave-wave interaction, wave breaking, and wave refraction and diffraction. The atmospheric numerical model also defines the parameterization method and subgrid-scale processes. The open boundary conditions of the ocean circulation model consist of the superposition of water levels and currents provided by the global ocean circulation dataset and astronomical tide levels and currents. The astronomical tide coefficient data is derived from the global ocean tide model (TPXO9) developed by Oregon State University. It includes 15 major tidal components commonly found in coastal areas worldwide: M2, N2, K2, S2, K1, O1, P1, Q1, S1, 2N2, M4, MF, MM, MN4, and MS4. After correction by astronomical factors, the interpolated values ​​are used as tidal forcing. It should be noted that the bottom friction scheme used is quadratic bottom friction, and the turbulence model uses the MY25 turbulence closure scheme. The ocean wave model utilizes the JONSWAP wave spectrum, accounting for wave-wave interaction, wave breaking, and wave refraction and diffraction. The atmospheric numerical model employs common parameterization methods and sub-grid-scale processes used in previous meteorological studies of target areas, modeling phenomena smaller than the grid scale and improving the accuracy of local wind fields.

[0133] S202 : Transmitting the physical fields corresponding to each preset mode through a data coupler.

[0134] For example, at each coupling moment, each preset model is solved through the corresponding set of control equations to obtain the required physical fields (such as water level, wind stress, wave height, etc.). The solution results are transmitted in real time between the three modes through the MCT coupler.

[0135] S203. The data coupler automatically routes the obtained physical field and interpolates the physical field corresponding to each preset mode into the corresponding target grid to obtain mapped field variables, which include hydrodynamic data and wave element data.

[0136] For example, the MCT coupler extracts the physical fields (such as water, wind stress, and wave height) output by each mode and sends them to the corresponding preset mode through automatic routing. The physical fields received by the receiving end generate mapped field variables through grid interpolation, which serve as the input for calculation at the next moment, realizing real-time interaction of the atmosphere-ocean-wave multi-physical fields and ensuring the calculation accuracy of dynamic inundation information (such as inundation range and water depth).

[0137] Among them, hydrodynamic data includes, but is not limited to, data related to ocean circulation patterns, such as sea surface water level (still water level, storm surge level), current velocity, seawater temperature, etc.; wave element data includes, but is not limited to, data related to ocean wave patterns, such as wave height (wave height), the time interval between adjacent waves passing through a fixed point (wave period), the direction of wave propagation (wave direction), the horizontal distance between adjacent wave crests (wavelength), etc. In addition, in other embodiments, in order to obtain more accurate results, relevant data from atmospheric numerical models may also be obtained, such as wind speed, wind direction, sea surface pressure, etc.

[0138] In one embodiment, the hydrodynamic data includes the static water level in front of the coastal protection structure in each calculation unit, and the wave element data includes the wave wavelength, significant wave height and wave direction in front of the coastal protection structure in each calculation unit. It is understandable that the hydrodynamic data includes but is not limited to the static water level in front of the coastal protection structure in each calculation unit, and the wave element data includes but is not limited to the wave wavelength in front of the coastal protection structure in each calculation unit. By obtaining the static water level and calculating the difference between it and the top elevation of the coastal protection structure, it is determined whether overflow will occur. If the static water level exceeds the elevation of the top of the structure, seawater will continuously flow through the top, causing flooding behind the dike. As the core output of the ocean circulation model, the real-time updated static water level data can predict the flooding range at different times. By obtaining the wave wavelength and the terrain slope in front of the coastal protection structure, and inputting them into the dynamic coupling calculation model of the coastal protection structure overflow and wave topping model, it is possible to determine whether wave topping can occur in the target area.

[0139] In one embodiment, in step S300, dividing the coastal protection structure of the target area into a plurality of calculation units includes:

[0140] Based on the target grid, the coastal protection structure in the target area is divided into multiple calculation units.

[0141] It can be understood that by meshing the coastal protection structures using any of the three preset target grids, the coastal protection structures in the target area are divided into multiple calculation units. For example, if the ocean circulation model uses a 50m x 50m grid and the coastal protection structures in the target area are 1.5 kilometers long, the coastal protection structures are divided into 30 calculation units using the target grid of the ocean circulation model. By calculating the actual conditions within a single calculation unit, the inundation volume within each calculation unit is calculated separately, improving the accuracy of the calculation. Wave overtopping and overflow can be calculated separately for shallow and deep water sections, avoiding errors caused by simulation.

[0142] In one embodiment, in step S400, based on the hydrodynamic data, wave element data, and the constructed dynamic coupling calculation model of the coastal protection structure overflow and wave overtopping model, determining the total amount of inundation behind the coastal protection structure in each calculation unit includes:

[0143] S401. Determine the top elevation of the coastal protection structure in the target area;

[0144] Exemplarily, the collective pattern and top elevation of the coastal protection structures in the target area are obtained, wherein the top elevation is the vertical height of the top of the coastal protection structure from the sea level.

[0145] S402: Based on the top elevation of the coastal protection structure in the target area, determine the top elevation of the coastal protection structure in each calculation unit.

[0146] For example, the top elevation data of the overall structure is mapped to each calculation unit. If the top elevation of the coastal protection structure is consistent along the length direction, the corresponding top elevations in all calculation units are the same. If there are height changes in the coastal protection structure, the values ​​are assigned separately according to the positions of the calculation units.

[0147] S403: Determine the unit overflow of the coastal protection structure per unit length in each calculation unit based on the top elevation and hydrodynamic data of the coastal protection structure in each calculation unit.

[0148] For example, the static water level, wave run-up height and top elevation in each calculation unit are obtained through the atmosphere-ocean circulation-wave coupling model to obtain the unit overflow of the coastal protection structure within a unit length.

[0149] S404: Based on the top elevation of the coastal protection structure in each calculation unit and the wave element data, obtain the unit wave top elevation of the coastal protection structure within a unit length.

[0150] The wave parameters of each calculation unit, such as wave height, wave period, wavelength, structure top elevation of each calculation unit and terrain slope, are obtained through the atmosphere-ocean circulation-wave coupling model, and the unit wave top elevation of the coastal protection structure within unit length is obtained.

[0151] S405. Based on the unit overflow volume and the unit wave overtopping volume, the total amount of inundation behind the coastal protection structure in each calculation unit is obtained.

[0152] For example, the combined values ​​of unit overflow and unit wave overtopping within each unit are calculated based on the combination of different inundation scenarios. The total unit inundation behind the coastal protection structure within each calculation unit is obtained. The total unit inundation is then multiplied by the length of the coastal protection structure to obtain the total inundation of the entire target area. The output data of overflow and wave overtopping are integrated to achieve integrated simulation results and improve the integrity of the assessment. This avoids the drawback of single models that ignore interactions and provides accurate, scientific, and comprehensive technical support for risk assessment, design optimization, and emergency management of coastal protection projects.

[0153] In one embodiment, in step S403, based on the top elevation and hydrodynamic data of the coastal protection structure in each calculation unit, the unit overflow volume of the coastal protection structure per unit length in each calculation unit is determined using the formula:

[0154] ,

[0155] in, is the overflow of the coastal protection structure in each calculation unit, g is the acceleration of gravity, It is the distance between the still water level in front of the coastal protection structure in each calculation unit and the top elevation of the coastal protection structure in each calculation unit.

[0156] For example, under extreme weather conditions, offshore water levels can exceed the top elevation of natural barriers or coastal protection structures, causing overflows. Domestic coastal protection structures are generally flat-topped, so a weir flow formula for wide-top structures is used to simulate coastal protection structure overflows during storms. The static water level in front of the coastal protection structure within each computational cell is obtained from the target grid of the ocean circulation model.

[0157] In one embodiment, in step S404, based on the top elevation of the coastal protection structure and the wave element data in each calculation unit, the unit wave top elevation of the coastal protection structure within a unit length is obtained, and the formula used is:

[0158]

[0159] in, is the wave crest value of the coastal protection structure in each calculation unit, is the maximum wave run-up height in front of the coastal protection structure in each calculation unit, is the significant unbroken wave height, , is the terrain slope in front of the coastal protection structure in each calculation unit, and is Determine the non-dimensional factor, where:

[0160]

[0161] It should be noted that if the wave encounters a structure during its forward propagation, Figure 2 , water will climb vertically along the structure and surge over natural barriers or coastal protection structures. In view of the characteristics of waves surge over coastal protection structures, this embodiment adopts an improved IFORM formula to calculate the wave cresting of unit length coastal protection structures. Compared with the traditional IFORM formula that uses a continuous non-size coefficient distribution, the improved IFORM formula adopted in this embodiment performs multi-segment function fitting on the non-size coefficient distribution based on a large amount of experimental data, so that it is more consistent with the distribution range of the measured data.

[0162] in, The maximum wave run-up height in front of the coastal protection structure in each calculation unit can be calculated using the following formula:

[0163]

[0164] in, is the oblique wave refraction coefficient, represents the climb height exceeded by 2% of the incident waves. The following formula can be used for calculation:

[0165]

[0166] in, Refers to the wavelength of the waves and is provided in real time via the target grid of the wave pattern. An imaginary slope is introduced to take into account the actual composite profile of the actual seabed and coastal protection structure. , where A is the cross-sectional area between the wave breaking point and the maximum wave run-up height, The water depth at which the wave breaks is to be determined.

[0167] It should be noted that the wave breaking depth is yet to be determined. , unbroken significant wave height The wave breaking point A is obtained by the following dynamic tracking method. At each time step, the effective wave height of any target grid corresponding to the three preset modes is first used to calculate the water depth when the wave breaks through the random wave transformation method. , where the calculation formula of the random wave transformation method is:

[0168]

[0169]

[0170]

[0171]

[0172]

[0173] in, The topographic slope representing the area in front of the coastal protection structure is provided by the bathymetric topographic conditions of the wave pattern.

[0174] like If the water depth is greater than the current calculation unit, move one calculation unit to the sea side and recalculate Repeat this process until the The wave height of the next calculation unit to the sea is the unbroken significant wave height. Therefore, it is used to extract the water depth when the wave breaks. , unbroken significant wave height The position of the calculation unit where the wave breaking point A is located will be adjusted with the dynamic changes of the water surface.

[0175] When waves are incident at an oblique angle, the wave crest rate per unit length of the coastal protection structure mainly depends on the wave direction. Therefore, the reduction coefficient of the wave crest rate under short wave conditions can be used to take into account the reduction of the wave crest rate caused by oblique waves. In this embodiment, the reduction coefficient is calculated based on the angle between the wave direction and the coastal protection structure direction at the calculation unit in the non-wave-breaking zone. , using the following formula:

[0176]

[0177] Among them, is the wave incidence angle. When applying the oblique wave reductance factor, it is assumed that there is a one-to-one correspondence between individual calculation cells in the non-wave-breaking zone and the wave source point that triggers wave cresting. Furthermore, the dynamic tracking of water depth and wave height in the non-wave-breaking zone in front of coastal protection structures can significantly affect the accuracy of wave crest calculations by extrapolating the source point further offshore.

[0178] For example, given the complex coastal terrain, when it is necessary to trace back the waves that caused the wave cresting of the coastal protection structure grid, it is difficult to trace the wave source path along the diagonal direction of the offshore grid. Therefore, this embodiment adopts the average grid point method to obtain wave information, that is, the average value of the wave direction of several calculation units around the assumed offshore location is taken as the reference value for calculating the wave cresting amount. Figure 3 , where the orange grid area represents the divided multi-section coastal protection structure, the brown grid represents a section of coastal protection structure to be calculated, the green grid area represents the grid range used to obtain the average wave direction, and the blue grid does not participate in the calculation of the average wave direction.

[0179] In one embodiment, step S405, the step of obtaining the total amount of inundation behind the coastal protection structure in each calculation unit based on the unit overflow volume and the unit wave overtopping volume, includes:

[0180] S451. Superimpose the unit overflow volume and the unit wave overtopping volume according to the combination corresponding to different inundation scenarios to obtain the total inundation volume behind the coastal protection structure within a unit length.

[0181] For example, based on historical data and research, there are multiple scenarios for flooding of coastal areas protected by coastal protection structures: 1. There are weak waves when the water level is lower than the top elevation of the coastal protection structure, and there is no flooding behind the coastal protection structure ( Figure 2 2. When the water level is lower than the top elevation of the coastal protection structure, there are strong waves, and the coastal protection structure is overwhelmed by the waves, causing the rear part to be submerged ( Figure 2 3. When the water level is higher than the top elevation of the coastal protection structure, the wave height is greater than the distance between the still water level and the top elevation of the coastal protection structure. At this time, the rear of the coastal protection structure is affected by both overflow inundation and wave top inundation ( Figure 2 (c) and the total inundation is controlled by both the water level in front of the coastal protection structure and the wave height taking into account the reflection effect of the coastal protection structure. 4. When the water level is significantly higher than the top elevation of the coastal protection structure or the water level is higher than the top elevation of the coastal protection structure but the wave height is small, the total inundation will be completely affected by the overflow and the wave crest can be ignored ( Figure 2 In order to cover various flooding scenarios, the total flooding behind the coastal protection structure per unit length is calculated using the following formula:

[0182]

[0183]

[0184] in, is the total flooding behind the coastal protection structure per unit length, represents the effective wave height considering the reflection effect and run-up effect of coastal protection structures, The calculation is performed using the following formula:

[0185]

[0186] S452. Based on the target grid, determine the length of the coastal protection structure in each calculation unit.

[0187] S453. Multiply the total inundation volume behind the coastal protection structure within a unit length by the length of the coastal protection structure within each calculation unit to obtain the total inundation volume behind the coastal protection structure within each calculation unit.

[0188] For example, the total inundation behind a unit length of coastal protection structure is calculated and then multiplied by the length of each section of the coastal protection structure to obtain the total inundation behind each section of the coastal protection structure. The total inundation behind the coastal protection structure is dynamically calculated to reflect in real time the total inundation caused by the synergistic effect of overflow and wave cresting. Based on the total inundation, dynamic inundation information of the target area is generated in real time, which is beneficial to the composite flood risk assessment behind the coastal protection structure under extreme meteorological conditions, the optimal design of coastal protection structures, and the construction of urban flood prevention and early warning systems. It solves the problem that the traditional phase-averaged wave numerical model fails when assessing the wave cresting of coastal protection structures, and the technical defects of the traditional coastal protection structure rear inundation calculation method that does not take into account dynamic wave conditions, oblique waves, and composite inundation processes. It significantly improves the calculation accuracy of inundation within composite coastal protection structures.

[0189] In one embodiment, after step S400, the method further includes:

[0190] The total amount of inundation behind the coastal protection structure in each calculation unit is added as a mass source and sink term to the calculation of the ocean circulation pattern in the atmosphere-ocean circulation-wave coupling model to correct the real-time hydrodynamic data of the target area.

[0191] For example, referring to Figure 5, the total amount of inundation behind the coastal protection structure in each calculation unit is added to the ocean circulation model as a mass source and sink term, so that it participates in the solution of the continuity equation and obtains the current water level of the target area in real time. The updated water level and flow field data of the ocean circulation model can be fed back to the wave model to correct the wave propagation speed and breaking position. The total inundation behind the coastal protection structure is dynamically calculated to reflect the total inundation caused by the synergistic effect of overflow and wave crest in real time. Based on the total inundation, dynamic inundation information of the target area is generated in real time, which is beneficial to the composite flood risk assessment behind the coastal protection structure under extreme meteorological conditions, the optimal design of the coastal protection structure and the construction of the urban flood prevention and warning system. It solves the problem that the traditional phase-averaged wave numerical model fails in evaluating the wave crest of the coastal protection structure and the technical defects of the traditional coastal protection structure rear inundation calculation method that does not take into account the dynamic wave conditions, oblique waves and composite inundation processes. It significantly improves the calculation accuracy of the inundation in the composite coastal protection structure.

[0192] Step S500, generating dynamic flooding information of the target area based on the total flooding amount, includes:

[0193] S501 , pre-processing digital elevation model data to obtain corrected digital elevation model data.

[0194] For example, the DEM data (digital elevation model data) of the target area is preprocessed to correct the terrain connectivity to obtain the corrected digital elevation model data, and the data defects such as pseudo-depressions and fault lines in the DEM (digital elevation model) are processed to ensure that the water flow path on the terrain surface is consistent with the actual situation.

[0195] S502: Determine the real-time water level elevation of the target area based on the total amount of inundation.

[0196] For example, the total inundation volume behind the coastal protection structure within a unit length is multiplied by the length of the coastal protection structure to obtain the total inundation volume behind the coastal protection structure. The surface volume tool is used to reversely infer the water level elevation of the area based on the total inundation volume to ensure the accuracy of the terrain data and avoid distortion of the inundation range simulation due to DEM data errors. The abstract total inundation volume is converted into specific water level elevation data to provide a benchmark for subsequent inundation analysis.

[0197] S503: Based on the corrected digital elevation model data and the real-time water level elevation, calculate the inundation range and inundation depth distribution of the target area in each time period according to a preset time step.

[0198] For example, referring to Figure 6, using active flooding, the overflow or wave crest position of the coastal protection structure is used as the source of seawater flooding, simulating the diffusion process of water from the front of the coastal protection structure to the back of the coastal protection structure. The area connected to the water flow is determined by watershed analysis or connectivity algorithm, and the flooding range is extracted. Specifically, watershed analysis determines the direction of water flow based on the terrain slope, divides different catchment areas, and identifies the range that may be flooded by seawater flooding. The connectivity algorithm determines which areas are connected to the source of seawater flooding in terms of terrain, and excludes areas blocked by terrain. Then, using the raster calculator, the water level elevation obtained by inversion is subtracted from the DEM data to generate a water depth distribution raster map.

[0199] S504: Generate dynamic flooding information of the target area based on the flooding range and flooding depth distribution of the target area in each time period.

[0200] For example, referring to Figure 7 By setting a time step, an automated model is constructed in the Model Builder, which iteratively calculates the inundation range within each time step. Combined with animation tools, the inundation range and water depth distribution within each time step are dynamically transformed, visually demonstrating the inundation process behind coastal protection structures. The inundation range and water depth distribution are overlaid with geographic data to generate a flood risk map, using different colors to represent water depth levels. This visual flood risk map transforms complex data into decision-making information, lowering the barrier to understanding for non-professionals.

[0201] In this way, the dynamic calculation method of the wave crest of the coastal protection structure corrected by oblique waves can simulate the lateral propagation distribution of waves along the coastal protection structure, more realistically reflect the climbing path of the wave crest on the surface of the coastal protection structure, and adopt a real-time interactive calculation and superposition method to calculate the composite inundation caused by the overflow of the coastal protection structure and the wave crest of the coastal protection structure. The real-time interactive superposition calculation can capture the nonlinear effect of the two: avoiding the defects of the traditional step-by-step calculation (calculating the overflow first and then the crest) that ignores the interaction, and integrating the coastal protection structure overflow calculation model and the coastal protection structure wave crest calculation model during extreme meteorological conditions into the atmospheric numerical model-regional ocean circulation model-wave model coupling model. At the same time, the post-inundation of the coastal protection structure caused by the functional failure of the coastal protection structure during the storm is used as the data drive of the geographic information analysis tool, so as to dynamically calculate the dynamic coastal inundation conditions under the influence of the overflow of the coastal protection structure and the wave crest of the coastal protection structure.

[0202] In an exemplary embodiment, a computer device is provided, including a processor and a memory, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of any one of the above-mentioned methods for determining dynamic flooding information based on overflow and wave dome are implemented.

[0203] In one exemplary embodiment, a computer-readable storage medium is provided, having a computer program stored thereon. When executed by a processor, the computer program implements the steps of any of the aforementioned methods for determining dynamic submergence information based on overflow and wave top. The computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, or the like.

[0204] In an exemplary embodiment, a computer program product is provided, comprising a computer program, which, when executed by a processor, implements the steps of any one of the above-mentioned methods for determining dynamic flooding information based on overflow and wave dome.

[0205] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, with the true scope and spirit of the invention being indicated by the claims.

[0206] It should be understood that the present invention is not limited to the exact construction described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A method for determining dynamic flooding information based on overflow and wave top, characterized in that: The method comprises: Constructing an atmosphere-ocean circulation-wave coupling model to divide a target area into target grids corresponding to three preset modes, wherein the three preset modes include an ocean circulation mode, an ocean wave mode, and an atmospheric numerical mode, and wherein a coastal protection structure is installed within the target area; Determining hydrodynamic data under the ocean circulation model and wave element data under the ocean wave model based on the atmosphere-ocean circulation-wave coupling model; dividing the coastal protection structure of the target area into a plurality of calculation units; Determine the total amount of inundation behind the coastal protection structure in each calculation unit based on the hydrodynamic data, the wave element data, and a dynamically coupled calculation model of the coastal protection structure overflow and wave overtopping model; generating dynamic flooding information of the target area based on the total flooding amount; The dynamic coupling calculation model based on the hydrodynamic data, the wave element data and the constructed coastal protection structure overflow and wave overtopping model, determining the total amount of inundation behind the coastal protection structure in each calculation unit includes: Determining the top elevation of the coastal protection structure in the target area; Determining the top elevation of the coastal protection structure in each of the calculation units based on the top elevation of the coastal protection structure in the target area; determining a unit overflow volume of the coastal protection structure per unit length in each calculation unit based on the top elevation of the coastal protection structure in each calculation unit and the hydrodynamic data; Based on the top elevation of the coastal protection structure in each calculation unit and the wave element data, obtaining the unit wave height of the coastal protection structure within a unit length; Based on the unit overflow volume and the unit wave overtopping volume, obtaining the total amount of inundation behind the coastal protection structure in each calculation unit; The step of obtaining the total amount of inundation behind the coastal protection structure in each calculation unit based on the unit overflow and the unit wave overtopping comprises: The unit overflow volume and the unit wave overtopping volume are superimposed according to the combination methods corresponding to different flooding scenarios to obtain the total flooding volume behind the coastal protection structure within a unit length; determining the length of the coastal protection structure within each of the calculation units based on the target grid; The total flooding volume behind the coastal protection structure within the unit length is multiplied by the length of the coastal protection structure within each calculation unit to obtain the total flooding volume behind the coastal protection structure within each calculation unit.

2. The method for determining dynamic flooding information based on overflow and wave top according to claim 1, characterized in that: The construction of the atmosphere-ocean circulation-wave coupling model includes: Dividing the target area into target grids corresponding to the three preset modes one by one; Acquiring water depth and terrain data required by each target grid, the water depth and terrain data including water depth data required by the ocean circulation model, water depth data required by the wave model, and terrain elevation and land use type required by the atmospheric numerical model; Obtaining the initial time data, full-time boundary grid data and control equations of each preset mode respectively; The initial time data and the boundary grid data of the entire time are interpolated into the corresponding target grid respectively, so that the initial time data and the boundary grid data of the entire time serve as the initial conditions and boundary conditions of the target grid.

3. The method for determining dynamic flooding information based on overflow and wave top according to claim 2, characterized in that: Determining the hydrodynamic data under the ocean circulation model and the wave element data under the ocean wave model based on the atmosphere-ocean circulation-wave coupling model includes: Based on the water depth topography data, the initial time data and the boundary grid data at all times, respectively solving the control equations corresponding to each preset mode by the finite difference method according to a preset time step, and obtaining the physical field corresponding to each preset mode at each coupling time; Transmitting the physical field corresponding to each of the preset modes through a data coupler; The data coupler automatically routes the obtained physical field and differs the physical field corresponding to each preset mode into the corresponding target grid to obtain mapped field variables, which include the hydrodynamic data and the wave element data.

4. The method for determining dynamic flooding information based on overflow and wave top according to claim 1, characterized in that: The hydrodynamic data includes the static water level in front of the coastal protection structure in each calculation unit, and the wave element data includes the wavelength, significant wave height and wave direction of the waves in front of the coastal protection structure in each calculation unit.

5. The method for determining dynamic flooding information based on overflow and wave top according to claim 4, characterized in that: Dividing the coastal protection structure of the target area into a plurality of calculation units comprises: Based on the target grid, the coastal protection structure of the target area is divided into a plurality of calculation units.

6. The method for determining dynamic flooding information based on overflow and wave top according to claim 1, characterized in that: The unit overflow of the coastal protection structure per unit length in each calculation unit is determined based on the top elevation of the coastal protection structure in each calculation unit and the hydrodynamic data, using the formula: ， in, is the overflow of the coastal protection structure in each calculation unit, g is the acceleration of gravity, It is the distance between the still water level in front of the coastal protection structure in each calculation unit and the top elevation of the coastal protection structure in each calculation unit.

7. The method for determining dynamic flooding information based on overflow and wave top according to claim 6, characterized in that: The unit wave height of the coastal protection structure per unit length is obtained based on the top elevation of the coastal protection structure and the wave element data in each calculation unit, and the formula used is: in, is the wave crest value of the coastal protection structure in each calculation unit, , is the slope in front of the coastal protection structure in each calculation unit, and is Determine the non-dimensional factor, where: is the maximum wave run-up height in front of the coastal protection structure in each calculation unit, The undetermined unbroken significant wave height in front of the coastal protection structure within each calculation unit.

8. The method for determining dynamic flooding information based on overflow and wave top according to claim 1, characterized in that: After the step of determining the total amount of inundation behind the coastal protection structure in each calculation unit based on the hydrodynamic data, the wave element data and the constructed coastal protection structure overflow and wave overtopping model, the step further includes: The total amount of inundation behind the coastal protection structure in each calculation unit is added as a mass source and sink term to the calculation corresponding to the ocean circulation model in the atmosphere-ocean circulation-wave coupling model to correct the real-time hydrodynamic data of the target area; The step of generating dynamic flooding information of the target area based on the total flooding amount includes: Preprocessing digital elevation model data to obtain corrected digital elevation model data; Determining the real-time water level elevation of the target area based on the total amount of inundation; Based on the corrected digital elevation model data and the real-time water level elevation, calculating the inundation range and inundation depth distribution of the target area in each time period according to a preset time step; Dynamic flooding information of the target area is generated based on the flooding range and flooding depth distribution of the target area in each time period.

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