Method and device for monitoring changes in regional groundwater reserves

Abstract

The application provides a regional groundwater storage change monitoring method and device, comprising the following steps: acquiring CORS station data, extracting geodetic height change data set according to the CORS station data; acquiring ground environmental load change data set; subtracting the part of the geodetic height change data caused by the ground environmental load from the geodetic height change data set according to the ground environmental load change data set to obtain a deformation residual data set, and constructing a deformation residual observation equation set according to the deformation residual data set; and inverting and calculating the deformation residual observation equation set to obtain a groundwater storage change data set. The geodetic height change data set with high spatial resolution and time resolution is acquired from the CORS station, the influence of the ground environmental load is removed to construct the deformation observation equation set, and then the groundwater storage change data set is obtained by inversion calculation, so that the groundwater storage change data set has the advantages of high spatial resolution and time resolution, and is beneficial to more accurately reflecting the regional groundwater change.

Description

Technical Field

[0001] This invention relates to the field of groundwater monitoring technology, and in particular to a method and equipment for monitoring changes in regional groundwater storage. Background Technology

[0002] Groundwater is an important component of the Earth's water cycle and a major source of water for domestic use, agricultural irrigation, and industrial production. Monitoring changes in groundwater is of great significance for the recycling and management of groundwater resources.

[0003] In existing technologies, groundwater change monitoring is mainly conducted through traditional groundwater monitoring stations, which can monitor parameters such as groundwater level, water quality, water temperature, and flow rate. However, the construction of groundwater monitoring stations requires significant resources, and the drilling process may disrupt the distribution of groundwater layers. Another monitoring method involves using gravity field changes monitored by gravity satellites GRACE and GRACE-FO, combined with hydrological models and other data, to calculate groundwater storage change datasets and achieve groundwater change monitoring.

[0004] However, monitoring through groundwater monitoring stations has low spatial resolution because these stations are mainly point monitoring systems with a small number of stations. In addition, monitoring through gravity satellites has low spatial resolution (about 300 km) for gravity field simulation and focuses on quarterly and annual changes for groundwater change research, resulting in low temporal resolution.

[0005] In summary, how to achieve high-resolution temporal and spatial monitoring of groundwater changes is an important issue that the industry urgently needs to address. Summary of the Invention

[0006] This invention provides a method and equipment for monitoring changes in regional groundwater storage, which addresses the shortcomings of low temporal and spatial resolution in existing technologies and achieves high-resolution groundwater change monitoring.

[0007] The groundwater monitoring method provided by this invention includes:

[0008] Acquire CORS station data, and extract geodetic height variation dataset based on the CORS station data;

[0009] Obtain a dataset of changes in surface environmental load;

[0010] Based on the above-ground environmental load change dataset, the earth height change data caused by the above-ground environmental load is subtracted from the earth height change dataset to obtain the deformation residual dataset. The deformation residual dataset is used to reflect the earth height change caused by groundwater. Based on the deformation residual dataset, a set of deformation residual observation equations is constructed.

[0011] The deformation residual observation equations are inverted to obtain a dataset of groundwater storage changes.

[0012] According to the method for monitoring regional groundwater storage changes provided by the present invention, the step of inverting and calculating the deformation residual observation equation set to obtain a groundwater storage change dataset includes:

[0013] Obtain the gravity residual observation equation set, which reflects the relationship between groundwater changes and gravity changes;

[0014] Based on the deformation residual observation equation set and the gravity residual observation equation set, the vertical deformation of groundwater load and the equilibrium vertical deformation are separated to obtain the groundwater storage change dataset.

[0015] According to the method for monitoring changes in regional groundwater storage provided by the present invention, the step of obtaining the gravity residual observation equation set includes:

[0016] Acquire gravity satellite data and / or ground gravity observation station data, and extract gravity change dataset based on the gravity satellite data and / or the ground gravity observation station data;

[0017] Based on the above-ground environmental load change dataset, the gravity change data caused by the above-ground environmental load is subtracted from the gravity change dataset to obtain gravity residual data. Based on the gravity residual data, a set of gravity residual observation equations is constructed.

[0018] According to the present invention, a method for monitoring changes in regional groundwater storage includes the following steps: Based on the deformation residual observation equation set and the gravity residual observation equation set, the method separates the vertical deformation of groundwater load and the equilibrium vertical deformation to obtain the groundwater storage change dataset.

[0019] The deformation residual observation equation set is inverted and calculated to obtain the first groundwater change dataset. The first groundwater change dataset reflects the equivalent water height change of the comprehensive vertical deformation of groundwater. There are multiple sets of the first groundwater change dataset within a preset time interval.

[0020] The gravity residual observation equations are inverted to obtain a second groundwater change dataset. The second groundwater change dataset reflects the equivalent water height change of the vertical deformation of the groundwater load. There is one set of the second groundwater change dataset within a preset time interval.

[0021] Subtract the second groundwater change dataset from one of the first groundwater change datasets within a preset time interval to obtain a third groundwater change dataset within the preset time interval. The third groundwater change dataset reflects the equivalent water height change of the equilibrium vertical deformation of groundwater.

[0022] The third groundwater change dataset is subtracted from each of the multiple sets of the first groundwater change datasets within a preset time interval to obtain the groundwater storage change dataset within the preset time interval.

[0023] According to the method for monitoring regional groundwater storage changes provided by the present invention, before the step of separating the vertical deformation of groundwater load and the equilibrium vertical deformation by inversion calculation based on the deformation residual observation equation set and the gravity residual observation equation set to obtain the groundwater storage change dataset, the method further includes:

[0024] Obtain hydrogeological data;

[0025] Based on the hydrogeological data, the unknowns of the equivalent groundwater height corresponding to the area without groundwater are removed from the deformation residual observation equation set and the gravity residual observation equation set.

[0026] According to the method for monitoring regional groundwater storage changes provided by the present invention, before the step of separating the vertical deformation of groundwater load and the equilibrium vertical deformation by inversion calculation based on the deformation residual observation equation set and the gravity residual observation equation set to obtain the groundwater storage change dataset, the method further includes:

[0027] The deformation residual observation equation set and the gravity residual observation equation set are regularized.

[0028] According to the method for monitoring changes in regional groundwater storage provided by the present invention, the step of acquiring a dataset of changes in aboveground environmental load includes:

[0029] Acquire regional and global surface environmental load data;

[0030] The above-ground environmental load data of the region are expanded using normalized spherical harmonic expansion to obtain the first spherical harmonic function;

[0031] The global surface environmental load data are expanded using normalized spherical harmonics to obtain a second spherical harmonic function.

[0032] Remove the spherical harmonic coefficients of the second spherical harmonic function from the spherical harmonic coefficients of the first spherical harmonic function to form the third spherical harmonic function;

[0033] The third spherical harmonic function is solved inversely to obtain the dataset of changes in the above-ground environmental load.

[0034] The present invention also provides an apparatus, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement a method for monitoring changes in regional groundwater storage as described above.

[0035] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a method for monitoring changes in regional groundwater storage as described above.

[0036] This invention provides a method for monitoring regional groundwater storage changes, which has at least the following advantages: The number of CORS (Continuous Operational Reference System) stations is large and widely distributed. By acquiring data from CORS stations in the monitoring area, a high-precision, continuously monitored geodetic height change dataset can be extracted. This method has the advantages of wide spatial distribution and high temporal monitoring density, i.e., high spatial and temporal resolution. Based on the surface environmental load change dataset, the geodetic height change portion caused by surface environmental loads such as atmosphere, surface water, and sea level is subtracted from the geodetic height change dataset. The remaining portion caused by groundwater changes is the deformation residual dataset. Based on this, a set of deformation residual observation equations is constructed. The groundwater storage change dataset is obtained by inversion calculation of the deformation residual observation equations. Thus, by acquiring a geodetic height change dataset with high spatial and temporal resolution from CORS stations, and by removing the influence of surface environmental loads to construct a set of deformation observation equations, the groundwater storage change dataset is obtained through inversion calculation. This results in a groundwater storage change dataset with both high spatial and temporal resolution, which is beneficial for more accurately reflecting regional groundwater changes. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0038] Figure 1 This is a schematic diagram of the main process of a method for monitoring changes in regional groundwater storage provided by the present invention;

[0039] Figure 2 This is one of the flowcharts of a method for monitoring changes in regional groundwater storage provided by the present invention;

[0040] Figure 3This is the second flowchart of a method for monitoring changes in regional groundwater storage provided by the present invention;

[0041] Figure 4 This is the third flowchart of a method for monitoring changes in regional groundwater storage provided by the present invention;

[0042] Figure 5 This is the fourth flowchart of a method for monitoring changes in regional groundwater storage provided by the present invention;

[0043] Figure 6 This is the fifth flowchart of a method for monitoring changes in regional groundwater storage provided by the present invention. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0045] The following is combined with Figures 1-6 A method for monitoring changes in regional groundwater storage according to the present invention includes:

[0046] S1: Obtain CORS station data and extract geodetic height variation dataset based on the CORS station data;

[0047] S2: Obtain the dataset of changes in surface environmental load;

[0048] S3: Based on the above-ground environmental load change dataset, subtract the part of the ground height change data caused by the above-ground environmental load from the ground height change dataset to obtain the deformation residual dataset. The deformation residual dataset is used to reflect the ground height change caused by groundwater. Based on the deformation residual dataset, construct a set of deformation residual observation equations.

[0049] S4: Invert the deformation residual observation equation set to obtain the groundwater storage change dataset.

[0050] CORS (Continuous Operational Reference System) stations are numerous and widely distributed. By acquiring CORS station data from the monitoring area, high-precision, continuously monitored geodetic height variation datasets can be extracted. This approach offers advantages such as wide spatial distribution and high temporal monitoring density, resulting in high spatial and temporal resolution. Based on the surface environmental load variation dataset, the geodetic height variation caused by surface environmental loads such as the atmosphere, surface water, and sea level is subtracted from the geodetic height variation dataset. The remaining portion, caused by groundwater, constitutes the deformation residual dataset. A set of deformation residual observation equations is then constructed, and the groundwater storage variation dataset is obtained through inversion calculation. In this way, a geodetic height variation dataset with high spatial and temporal resolution is obtained from CORS stations. By removing the influence of surface environmental loads and constructing a set of deformation observation equations, the groundwater storage variation dataset is obtained through inversion calculation. This results in a groundwater storage variation dataset with both high spatial and temporal resolution, which is beneficial for more accurately reflecting regional groundwater changes.

[0051] The principle for obtaining changes in groundwater storage is as follows: Based on the load-deformation theory, under the influence of loads such as the atmosphere, surface water, groundwater, and sea level, the earth will deform, leading to changes in ground height. The influence of these loads can be represented by equivalent water height, and the corresponding changes in ground height can be calculated using this equivalent water height. The changes in ground height include those caused by the atmosphere, surface water, groundwater, and sea level. Therefore, by subtracting the changes caused by the atmosphere, surface water, and sea level from the changes in ground height, the changes in ground height caused by groundwater are obtained. Then, based on the changes in ground height caused by groundwater, the equivalent changes in groundwater storage, i.e., the changes in groundwater storage, can be calculated.

[0052] Surface environmental loads include the load effects of the atmosphere, surface water, and sea level, and can be represented by equivalent water height. Equivalent water height can be calculated and converted into equivalent geodetic height changes. Surface environmental load change datasets can specifically include the equivalent geodetic height changes corresponding to the effects of the atmosphere, surface water, and sea level. These datasets can be obtained from environmental monitoring stations monitoring the atmosphere, surface water, and sea level in various locations.

[0053] Based on data from multiple CORS stations in the monitoring area, and combined with the location information of each CORS station, the geodetic height changes at the location of each CORS station and the geodetic height changes between CORS stations can be obtained, thus achieving the goal of extracting a geodetic height change dataset. This dataset can be presented in grid form, reflecting the total geodetic height change at each location point in the monitoring area. Similarly, the ground environmental load change dataset can also be presented in grid form, reflecting the geodetic height change at each location point in the monitoring area caused by the influence of ground environmental load.

[0054] The change caused by the ground environment load is subtracted from the geodetic height change dataset. Specifically, the total geodetic height change at the corresponding location point in the monitoring area is subtracted from the geodetic height change caused by the ground environment load to obtain the geodetic height residual value at that location point. The geodetic height residual values ​​of each location point in the grid constitute the geodetic height residual grid data, i.e., the deformation residual dataset.

[0055] Based on the deformation residual dataset, deformation residual observation equations can be constructed for each location point in the grid. The deformation residual observation equations corresponding to each location point in the grid constitute a deformation residual observation square group. In some embodiments of this invention, the deformation residual observation equations are specifically as follows:

[0056]

[0057] Where: Δr t This represents the deformation residual (geodetic height residual value). λ is the geocentric latitude of the calculation point on the ground; G is the gravitational constant; ρ is the geocentric longitude of the calculation point on the ground. w The density of water; λ is the geocentric latitude of the point of integration on the ground; ′ L is the geocentric longitude of the ground integration flow point; L is the spatial distance from the ground integration flow point to the ground calculation point; Δh w1 G represents the high variation value of groundwater equivalent water. r (ψ) is the radial Green's function; ψ is the spherical angular distance; S is the computational domain.

[0058] In the deformation residual observation equation, the change value Δh of the equivalent groundwater height is... w1 Since the variable is unknown, the equivalent groundwater height change value Δh can be obtained by inverting the deformation residual observation equation based on the deformation residual dataset. w1 As a value reflecting changes in groundwater storage, the groundwater storage change values ​​at each location point in the entire grid constitute a groundwater storage change dataset, which can reflect changes in groundwater storage in the monitoring area.

[0059] Based on the deformation residual dataset obtained from the geodetic height change dataset and the surface environmental load change dataset, the groundwater storage change dataset can be obtained by establishing the deformation residual observation equation and performing inversion calculation on the deformation residual observation equation. However, in the inversion calculation process, the equivalent groundwater height change value includes the influence of groundwater load vertical deformation and the influence of equilibrium vertical deformation.

[0060] The vertical deformation effect of groundwater load refers to the ground uplift or subsidence caused by the rise or fall of groundwater level under the action of groundwater load. The vertical deformation of groundwater load is related to the transient changes in groundwater level.

[0061] The effect of isostatic vertical deformation of groundwater refers to the volume change of soil or rock mass under the action of groundwater, which leads to ground uplift or subsidence. Isostatic vertical deformation of groundwater is usually a slow process that requires a long time to evolve.

[0062] Vertical deformation caused by groundwater load affects the gravitational field. When the vertical deformation changes, the density distribution of the surrounding geological medium also changes, leading to changes in the gravitational field. Isostatic vertical deformation of groundwater directly affects the ground surface (geodetic height) but has no direct impact on the gravitational field; it is only a localized deformation with minimal influence on the surrounding area. Therefore, the effects of groundwater load-induced vertical deformation and isostatic vertical deformation on the ground surface and gravity differ.

[0063] The influence of groundwater load vertical deformation can more accurately reflect the transient changes in groundwater level. In order to meet the application requirements of higher accuracy and further improve the accuracy of the obtained groundwater storage change dataset, it is necessary to separate the groundwater load vertical deformation from the equilibrium vertical deformation.

[0064] To achieve the effect of separating the vertical deformation caused by groundwater load from the equilibrium vertical deformation, refer to Figure 2 and Figure 3 In some embodiments of the present invention, S4 includes:

[0065] S41: Obtain the gravity residual observation equation set, which reflects the relationship between groundwater changes and gravity changes;

[0066] S42: Based on the deformation residual observation equation set and the gravity residual observation equation set, the vertical deformation of groundwater load and the equilibrium vertical deformation are separated to obtain the groundwater storage change dataset.

[0067] Based on the difference in the impact of groundwater load vertical deformation and equilibrium vertical deformation on the ground and gravity, the deformation residual observation equation and gravity residual observation equation are inverted and calculated. This can separate the groundwater load vertical deformation from the equilibrium vertical deformation, which is beneficial to improving the accuracy of the final groundwater storage change dataset.

[0068] refer to Figure 3 In some embodiments of the present invention, S41 includes:

[0069] S411: Acquire gravity satellite data and / or ground gravity observation station data, and extract gravity change dataset based on the gravity satellite data and / or the ground gravity observation station data;

[0070] S412: Based on the above-ground environmental load change dataset, subtract the gravity change data caused by the above-ground environmental load from the gravity change dataset, and construct a gravity residual observation equation set based on the gravity residual data.

[0071] Obtaining a gravity change dataset can reflect the gravity changes at various locations in the monitoring area. Based on the ground environmental load change dataset, the gravity changes caused by ground environmental loads such as the atmosphere, surface water, and sea level are subtracted from the gravity change dataset. The remaining gravity changes caused by groundwater are the gravity residual data, and the gravity residual observation equation is constructed accordingly.

[0072] The surface environmental load includes the load effects of the atmosphere, surface water, and sea level, which can be represented by the equivalent water height. The equivalent water height can be calculated and converted into the equivalent gravity change. The surface environmental load change dataset can include the equivalent gravity changes corresponding to the effects caused by the atmosphere, surface water, and sea level. The gravity change dataset can reflect the total gravity change at each location point in the form of a grid. Subtracting the change caused by the surface environmental load from the gravity change dataset—specifically, subtracting the gravity change caused by the surface environmental load from the total gravity change at the corresponding location point in the monitoring area—results in the gravity residual value for that location point. The gravity residual values ​​at each location point in the monitoring area constitute the gravity residual grid data, i.e., the gravity residual data.

[0073] Based on gravity residual data, gravity residual observation equations can be constructed for locations within the monitoring area, and the gravity residual observation equations corresponding to each location constitute a set of gravity residual observation equations. In some embodiments of the present invention, the gravity residual observation equations are specifically as follows:

[0074]

[0075] Where: Δg t This represents the gravity residual value; λ is the geocentric latitude of the calculation point on the ground; G is the gravitational constant; ρ is the geocentric longitude of the calculation point on the ground. w The density of water; λ is the geocentric latitude of the point of integration on the ground; ′ L is the geocentric longitude of the ground integration flow point; L is the spatial distance from the ground integration flow point to the ground calculation point; Δh w2 G represents the high variation value of groundwater equivalent water. g (ψ) is the gravitational Green's function; ψ is the spherical angular distance; S is the computational domain.

[0076] The equivalent groundwater height variation value Δh is obtained from the inversion calculation based on the deformation residual observation equation. w1 And the equivalent water height variation value Δh of groundwater obtained by inversion calculation of gravity residual observation equation. w2 Combining the differences in the effects of groundwater load vertical deformation and equilibrium vertical deformation on the ground surface and gravity, specifically, the change value Δh of the equivalent groundwater height. w1 This includes the effects of groundwater load on vertical deformation and the change in equivalent groundwater height Δh. w2 The vertical deformation effect of the load, including groundwater, will thus affect the Δh at the same location. w1 Subtract Δh w2 This allows us to obtain the equivalent water height change value corresponding to the effect of equilibrium vertical deformation, thus achieving the effect of separating the vertical deformation of groundwater load from the equilibrium vertical deformation.

[0077] It should be noted that gravity variation datasets obtained from gravity satellites and / or ground-based gravity observation stations may have relatively lower temporal resolution compared to geodetic height variation datasets obtained from continuously operating CORS stations. Therefore, the equivalent groundwater height variation value Δh obtained based on the gravity variation dataset may have a lower temporal resolution. w2 While it can directly reflect the vertical deformation of groundwater load, its temporal resolution is relatively low. In contrast, the equivalent groundwater height variation value Δh obtained based on the geodetic height variation dataset... w1 Although it has high temporal resolution, it includes both the vertical deformation due to groundwater load and the equilibrium vertical deformation. To obtain groundwater equivalent height variation values ​​with high temporal resolution that accurately reflect transient groundwater level changes, reference... Figure 4 In some embodiments of the present invention, S42 includes:

[0078] S421: Invert the deformation residual observation equation set to obtain the first groundwater change dataset. The first groundwater change dataset reflects the equivalent water height change of the comprehensive vertical deformation of groundwater. There are multiple sets of the first groundwater change dataset within a preset time interval.

[0079] S422: Invert the gravity residual observation equation set to obtain the second groundwater change dataset. The second groundwater change dataset reflects the equivalent water height change of the vertical deformation of the groundwater load. There is one set of the second groundwater change dataset within a preset time interval.

[0080] S423: Subtract the second groundwater change dataset from one of the first groundwater change datasets within a preset time interval to obtain a third groundwater change dataset within a preset time interval. The third groundwater change dataset reflects the equivalent water height change of the groundwater equilibrium vertical deformation.

[0081] S424: Subtract the third groundwater change dataset from multiple sets of the first groundwater change datasets within a preset time interval to obtain the groundwater storage change dataset within the preset time interval.

[0082] For ease of distinction and description, the change value Δh of the equivalent groundwater height will be used. w1 This is called the first groundwater change value, and the equivalent groundwater height change value Δh is used to calculate the change value. w2 This is referred to as the second groundwater change value. The first groundwater change value Δh corresponds to each location point within the monitoring area. w1 The first groundwater change dataset is constructed, and the second groundwater change value Δh is corresponding to each location point within the monitoring area. w2 This constitutes a second groundwater change dataset. It includes the Δh values ​​corresponding to the same location and time point. w1 Subtract Δh w2 It can remove Δh w1 The portion including the load vertical deformation influence is used to obtain the third groundwater change value Δh, which reflects the influence of the equilibrium vertical deformation at the corresponding location point. w1 -Δh w2 The change value Δh of the third groundwater at each location point in the monitoring area w1 -Δh w2 This constitutes the third groundwater change dataset.

[0083] Based on the characteristic that the vertical deformation of groundwater equilibrium requires a long time to evolve, that is, the change is small in a short time, the change value Δh of the third groundwater at a certain time point t0 within the preset time interval t1~t2 can be used. w1 (t0)-Δh w2 (t0) is taken as the equivalent water height change value corresponding to the balanced vertical deformation within the preset time interval t1~t2, and Δh within the preset time interval t1-t2 is used. w1 (tx) minus Δh w1 (t0)-Δh w2 (t0) can obtain a high-resolution and accurate fourth groundwater change value Δh that reflects transient groundwater level changes. w1(tx)-Δh w1 (t0)-Δh w2 (t0), the fourth groundwater change value Δh corresponding to each location point in the monitoring area. w1 (tx)-Δh w1 (t0)-Δh w2 (t0) constitutes a dataset of groundwater storage changes within a preset time interval.

[0084] Based on the difference between groundwater load vertical deformation and equilibrium vertical deformation, deformation residual observation equations and gravity residual observation equations are constructed using geodetic height variation datasets, gravity variation datasets, and surface environmental load variation datasets. The influence of groundwater load vertical deformation and equilibrium vertical deformation is then calculated and separated, ultimately obtaining a high-resolution groundwater storage change dataset that accurately reflects transient groundwater level changes.

[0085] To make it easier to understand, let's take a concrete example. Gravity change datasets might be monitored on a monthly basis, such as the gravity change at a certain location: "January 1st: g1; February 1st: g2; ...". The second groundwater change value Δh is obtained by constructing a gravity residual observation equation based on the gravity change dataset and calculating it. w2 Also measured in months, such as the change in groundwater level Δh at the corresponding location point. w2 For: "January 1st: Δh" w2 (t1); February 1: Δh w2 (t2); ……. The geodetic height variation dataset has a higher time resolution, possibly in weekly units. For example, the geodetic height variation at a certain location might be: “January 1st: r11; January 8th: r12; ... February 5th: r21; February 12th: r22; ……”. The first groundwater change value Δh is obtained by inverting the deformation residual observation equation based on the geodetic height variation dataset. w1 It is also expressed in weeks, such as the change in groundwater at the corresponding location point, Δh. w2 For: "January 1st: Δh" w1 (t11); January 8: Δh w1 (t12); ... February 5th: Δh w1 (t21); February 12: Δh w1 (t22); ……. In this case, the preset time interval is 1 month, which can be used to determine the first groundwater change value Δh at the same location on January 1st. w1 (t11) minus the second groundwater change value Δh w2 (t1), the third groundwater change value Δh is obtained as the effect of the equilibrium vertical deformation during the preset time interval from January 1 to January 31. w1 (t11)-Δhw2 (t1), and the changes in the fourth groundwater level from January 1st to January 31st are as follows: "January 1st: Δh w2 (t1); January 8: Δh w1 (t12)-Δh w1 (t11)+Δh w2 (t1); January 15: Δh w1 (t13)-Δh w1 (t11)+Δh w2 (t1); ……. Compared to using gravity to obtain groundwater changes on a monthly basis, the above process can accurately reflect the transient changes in groundwater levels on a weekly basis, i.e., a higher time resolution. The fourth groundwater change value at each location point constitutes a groundwater storage change dataset. It should be noted that the above example is only for ease of understanding. In actual applications, the time resolution of gravity change datasets may not be on a monthly basis, and the time resolution of geodetic height change datasets may not be on a weekly basis. The preset time interval is generally determined based on the time resolution of gravity change datasets.

[0086] refer to Figure 5 In some embodiments of the present invention, prior to S42, the following step is further included:

[0087] S413: Obtain hydrogeological data;

[0088] S414: Based on the hydrogeological data, remove the unknowns of the equivalent groundwater height corresponding to the area without groundwater from the deformation residual observation equation set and the gravity residual observation equation set.

[0089] By acquiring existing hydrogeological data, including existing groundwater observation data and groundwater detection data, it is possible to identify areas with and without groundwater within the monitoring region. For areas without groundwater, there is no need to perform inversion calculations on the deformation residual equations and gravity residual equations corresponding to those areas. Therefore, by removing the unknowns of the equivalent groundwater height corresponding to areas without groundwater from the deformation residual observation equations and gravity residual observation equations based on the hydrogeological data, the number of unknowns can be reduced before inversion calculations, which is beneficial to improving the efficiency of inversion calculations.

[0090] refer to Figure 5 In some embodiments of the present invention, prior to S42, the following step is further included:

[0091] S415: Regularize the set of deformation residual observation equations and the set of gravity residual observation equations.

[0092] Since the inversion calculation involves many parameters, the results are not easy to converge. Therefore, regularizing the residual observation equations and gravity residual observation equations can prevent overfitting during the inversion calculation, making the results easier to converge and more stable.

[0093] For specific regularization processing, commonly used regularization methods can be adopted, such as L1 norm regularization, L2 norm regularization, Tikhonov regularization, etc.

[0094] refer to Figure 6 In some embodiments of the present invention, S2 includes:

[0095] S21: Obtain regional and global surface environmental load data;

[0096] S22: Normalize the spherical harmonic expansion of the above-ground environmental load data of the area to obtain the first spherical harmonic function;

[0097] S23: Normalize the global surface environmental load data using spherical harmonic expansion to obtain the second spherical harmonic function;

[0098] S24: Remove the spherical harmonic coefficient set of the second spherical harmonic function from the spherical harmonic coefficient set of the first spherical harmonic function to form the third spherical harmonic function;

[0099] S25: Solve the third spherical harmonic function in reverse to obtain the dataset of changes in the aboveground environmental load.

[0100] When analyzing the monitoring area, the regional ground environmental load data corresponding to changes in the ground environmental load within the monitoring area includes the impact of global ground environmental load changes. The long-distance effect of global ground environmental load on the monitoring area increases the complexity of the inversion calculation process, while in reality, the impact of global ground environmental load on the monitoring area is almost negligible. Therefore, by performing normalized spherical harmonic expansion on the regional and global ground environmental load data respectively, a first spherical harmonic function and a second spherical harmonic function are obtained. The spherical harmonic coefficients of the second spherical harmonic function are removed from the spherical harmonic coefficient set of the first spherical harmonic function to form a third spherical harmonic function. In this way, the impact of global ground environmental load changes can be removed from the regional ground environmental load changes. The ground environmental load change dataset is obtained by inversely solving the third spherical harmonic function. Therefore, by using spherical harmonic expansion, the influence of global ground environmental load can be removed from regional ground environmental load data, thus eliminating the influence of far-field load. Then, the influence of near-field load can be recovered by inversely solving the spherical harmonic function, obtaining the required ground environmental load change dataset. This transforms the subsequent unknown inversion calculation problem involving large-scale ground environmental load into an unknown inversion calculation problem within a local effective distance, which helps to reduce the unknowns involved in subsequent inversion calculations and lower the complexity of the inversion calculation.

[0101] Regional surface environmental load data can be measured data from monitoring stations in the monitored area, while global surface environmental load data can be derived from satellite measurement data or existing model data.

[0102] It should be noted that the surface environmental load includes the atmosphere, surface water, and sea level, and each needs to undergo the aforementioned normalized spherical harmonic expansion, removal, and inverse solution processes separately. All surface environmental loads can be represented by equivalent water height. Normalized spherical harmonic expansion is performed based on the equivalent water height. In some embodiments of this invention, the equivalent water height Δh... w The expansion is as follows:

[0103]

[0104] After removing the corresponding spherical harmonic coefficients, during the inverse solution, the changes in geodetic height and gravity caused by the equivalent water height can be calculated separately. In some embodiments of the present invention, the change in geodetic height Δr is calculated using the following formula:

[0105]

[0106] In some embodiments of the present invention, the change in gravity Δg is calculated using the following formula:

[0107]

[0108] In the above formula: λ represents the geocentric latitude of the ground calculation point; λ represents the geocentric longitude of the ground calculation point. The normalized load spherical harmonic coefficients are of order n and order m. h′ is the nth-order m-th normalized association Legendre function; n k′ is the Love number for the nth order radial load. n ρ is the Love number for n-order positional loads. w ρ is the density of water. e γ is the Earth's average density; G is the gravitational constant; M is the Earth's total mass; R is the Earth's average radius; and γ is the average gravity at the Earth's surface.

[0109] In some embodiments of the present invention, before S24, the method further includes: removing spherical harmonic coefficients with frequencies lower than a preset threshold from the first spherical harmonic function.

[0110] Since the above-ground environmental load includes the influence of ultra-shortwave loads—that is, load influences caused by accidental factors with very short durations—these should be separated. After performing spherical harmonic expansion on the regional above-ground load data, different spherical harmonic coefficients correspond to basis functions of different frequencies. Removing spherical harmonic coefficients with frequencies below a preset threshold can eliminate the influence of ultra-shortwave loads in the above-ground environmental load, which is beneficial for subsequent inversion calculations to be more stable, improve accuracy, and reduce interference from accidental factors.

[0111] All measurement data, observation data and parameters involved in the calculation should strictly adopt unified numerical standards and geophysical models, and remove solid tides, ocean tide loads, atmospheric tide loads, polar motion effects and geocentric motion effects through appropriate algorithms, and reduce the changes to a suitable reference epoch, and unify the time reference for deformation monitoring.

[0112] The following describes a device provided by the present invention. The device described below can be referred to in correspondence with the method for monitoring changes in regional groundwater storage described above.

[0113] This invention also provides a device including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the above-described method for monitoring changes in regional groundwater storage.

[0114] The device can be a computer, mobile phone, etc. The processor in it executes the computer program in the memory, which can obtain a geodetic height change dataset with high spatial and temporal resolution from the CORS station. By removing the influence of the surface environmental load, a set of deformation observation equations is constructed, and the groundwater storage change dataset is obtained by inversion calculation. This makes the groundwater storage change dataset have the advantages of high spatial and temporal resolution, which is conducive to more accurately reflecting the groundwater changes in the region.

[0115] This invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the aforementioned method for monitoring changes in regional groundwater storage.

[0116] The computer program stored in the storage medium is executed, which can obtain a geodetic height change dataset with high spatial and temporal resolution from the CORS station. By removing the influence of the surface environmental load, a set of deformation observation equations is constructed, and the groundwater storage change dataset is obtained through inversion calculation. This makes the groundwater storage change dataset have the advantages of high spatial and temporal resolution, which is conducive to more accurately reflecting the groundwater changes in the region.

[0117] This invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute each of the above-described methods for monitoring changes in regional groundwater storage. It can obtain geodetic height change datasets with high spatial and temporal resolution from CORS stations, construct a set of deformation observation equations by removing the influence of surface environmental loads, and inversely calculate and obtain groundwater storage change datasets. This gives the groundwater storage change datasets the advantages of high spatial and temporal resolution, which is beneficial for more accurately reflecting the changes in regional groundwater.

[0118] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0119] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for monitoring changes in regional groundwater storage, characterized in that, include: Acquire CORS station data, and extract geodetic height variation dataset based on the CORS station data; Obtain a dataset of changes in surface environmental load; Based on the above-ground environmental load change dataset, the earth height change data caused by the above-ground environmental load is subtracted from the earth height change dataset to obtain the deformation residual dataset. The deformation residual dataset is used to reflect the earth height change caused by groundwater. Based on the deformation residual dataset, a set of deformation residual observation equations is constructed. The deformation residual observation equations are inverted and calculated to obtain a dataset of groundwater storage changes. The inversion calculation of the deformation residual observation equation set yields a groundwater storage change dataset, including: Acquire gravity satellite data and / or ground gravity observation station data, and extract gravity change dataset based on the gravity satellite data and / or the ground gravity observation station data; Based on the above-ground environmental load change dataset, the gravity change data caused by the above-ground environmental load is subtracted from the gravity change dataset to obtain gravity residual data. Based on the gravity residual data, a set of gravity residual observation equations is constructed, which reflects the relationship between groundwater changes and gravity changes. Based on the deformation residual observation equation set and the gravity residual observation equation set inversion calculation, the vertical deformation of groundwater load and the equilibrium vertical deformation are separated to obtain the groundwater storage change dataset. The process involves inverting and calculating based on the deformation residual observation equations and the gravity residual observation equations to separate the vertical deformation of groundwater load and the equilibrium vertical deformation, thereby obtaining the groundwater storage change dataset, including: The deformation residual observation equation set is inverted and calculated to obtain the first groundwater change dataset. The first groundwater change dataset reflects the equivalent water height change of the comprehensive vertical deformation of groundwater. There are multiple sets of the first groundwater change dataset within a preset time interval. The gravity residual observation equations are inverted to obtain a second groundwater change dataset. The second groundwater change dataset reflects the equivalent water height change of the vertical deformation of the groundwater load. There is one set of the second groundwater change dataset within a preset time interval. Subtract the second groundwater change dataset from one of the first groundwater change datasets within a preset time interval to obtain a third groundwater change dataset within the preset time interval. The third groundwater change dataset reflects the equivalent water height change of the equilibrium vertical deformation of groundwater. The third groundwater change dataset is subtracted from each of the multiple sets of the first groundwater change datasets within a preset time interval to obtain the groundwater storage change dataset within the preset time interval.

2. The method for monitoring changes in regional groundwater storage according to claim 1, characterized in that, Before obtaining the groundwater storage change dataset by separating the vertical deformation of groundwater load and the equilibrium vertical deformation based on the inversion calculation of the deformation residual observation equation set and the gravity residual observation equation set, the method further includes: Obtain hydrogeological data; Based on the hydrogeological data, the unknowns of the equivalent groundwater height corresponding to the area without groundwater are removed from the deformation residual observation equation set and the gravity residual observation equation set.

3. The method for monitoring changes in regional groundwater storage according to claim 1, characterized in that, Before obtaining the groundwater storage change dataset by separating the vertical deformation of groundwater load and the equilibrium vertical deformation based on the inversion calculation of the deformation residual observation equation set and the gravity residual observation equation set, the method further includes: The deformation residual observation equation set and the gravity residual observation equation set are regularized.

4. The method for monitoring changes in regional groundwater storage according to claim 1, characterized in that, The acquisition of the above-ground environmental load change dataset includes: Acquire regional and global surface environmental load data; The above-ground environmental load data of the region are expanded using normalized spherical harmonic expansion to obtain the first spherical harmonic function; The global surface environmental load data are expanded using normalized spherical harmonics to obtain a second spherical harmonic function. Remove the spherical harmonic coefficients of the second spherical harmonic function from the spherical harmonic coefficients of the first spherical harmonic function to form the third spherical harmonic function; The third spherical harmonic function is solved inversely to obtain the dataset of changes in the above-ground environmental load.

5. The method for monitoring changes in regional groundwater storage according to claim 4, characterized in that, Before removing the spherical harmonic coefficient set of the second spherical harmonic function from the spherical harmonic coefficient set of the first spherical harmonic function to form the third spherical harmonic function, the process further includes: Remove spherical harmonic coefficients with frequencies below a preset threshold from the first spherical harmonic function.

6. An apparatus comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements a method for monitoring changes in regional groundwater storage as described in any one of claims 1 to 5.

7. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements a method for monitoring changes in regional groundwater storage as described in any one of claims 1 to 5.

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