Quantitative analysis method for frozen soil ice-melt water runoff based on distributed hydrological model

Abstract

The invention relates to a frozen soil ice-melt water runoff quantitative analysis method based on a distributed hydrological model. The method comprises the following steps: dividing soil in a target area into at least one soil layer, and constructing a solid ice quality parameter corresponding to each soil layer; for any soil layer, determining a water migration path corresponding to the soil layer according to the position of the soil layer, and constructing a molten water mass parameter migration function corresponding to each water migration path according to a conversion relation between solid ice and molten water in the soil layer and the solid ice mass parameter corresponding to the soil layer; constructing a target distributed hydrological model corresponding to the target area based on the mass parameter migration functions of the molten water; and performing simulation processing on the water circulation process of the target area through the target distributed hydrological model, and determining the frozen soil ice melt water runoff volume of the target area according to the output value of the melt water quality parameter migration function corresponding to the runoff water migration path in the simulation result. By adopting the method, the cost of calculating the frozen soil ice-melt water runoff can be reduced.

Description

Technical Field

[0001] The present application relates to the field of distributed hydrological models, and in particular to a method for quantitative analysis of permafrost meltwater runoff based on a distributed hydrological model. Background Art

[0002] Cryosphere elements such as glaciers and permafrost play an important role in the hydrological cycle of watersheds and changes in river runoff. Accurately assessing the contribution of permafrost meltwater to runoff in high-altitude watersheds is crucial for predicting hydrological changes in high-altitude watersheds and adaptive management of water resources under climate change.

[0003] Related technologies typically use isotope labeling or synthetic aperture radar data to invert ground subsidence in permafrost areas, and empirical formulas to infer permafrost ice loss and its contribution to runoff. However, these methods are difficult to apply to larger watersheds and are relatively expensive. Summary of the Invention

[0004] Based on this, it is necessary to provide a quantitative analysis method for permafrost meltwater runoff based on a distributed hydrological model to address the above technical issues.

[0005] In a first aspect, the present application provides a method for quantitatively analyzing permafrost meltwater runoff based on a distributed hydrological model. The method comprises:

[0006] Dividing the soil in the target area into at least one soil layer, and constructing a solid ice mass parameter corresponding to each soil layer;

[0007] For any of the soil layers, a water migration path corresponding to the soil layer is determined based on the location of the soil layer, and a meltwater mass parameter migration function corresponding to each of the water migration paths is constructed based on the conversion relationship between solid ice and meltwater in the soil layer and the solid ice mass parameter corresponding to the soil layer; the water migration path includes at least a runoff water migration path;

[0008] Constructing a target distributed hydrological model corresponding to the target area based on each meltwater quality parameter migration function;

[0009] The water cycle process of the target area is simulated by the target distributed hydrological model to obtain a simulation result, and the permafrost meltwater runoff of the target area is determined based on the output value of the meltwater quality parameter migration function corresponding to the runoff moisture migration path in the simulation result.

[0010] In one embodiment, constructing the solid ice mass parameter corresponding to each soil layer includes:

[0011] For any of the soil layers, an ice content correlation parameter corresponding to the soil layer is determined, a soil ice mass of the soil layer is constructed based on the ice content correlation parameter, and the soil ice mass corresponding to the soil layer at a target time is used as a solid ice mass parameter corresponding to the soil layer.

[0012] In one embodiment, taking the soil ice mass corresponding to the soil layer at the target time as the solid ice mass parameter corresponding to the soil layer includes:

[0013] In the case where the soil layer includes permafrost, the soil ice mass corresponding to a first target time is used as the solid ice mass parameter, where the first target time is the time at which the soil thawing depth is the deepest among all times of the year;

[0014] In the case where the soil layer includes seasonal frozen soil, the soil ice mass at a second target time is used as the solid ice mass parameter, where the second target time is the time at which the soil freezing depth is the deepest among various times of the year.

[0015] In one embodiment, the method further comprises:

[0016] During the process of simulating the water cycle process of the target area by the target distributed hydrological model, obtaining the surface soil temperature from the current simulation result of the target distributed hydrological model;

[0017] When the surface soil temperature indicates that the soil begins to melt, it is determined that the second target time has been reached. When the surface soil temperature indicates that the soil begins to freeze, it is determined that the first target time has been reached.

[0018] In one embodiment, constructing a meltwater quality parameter migration function corresponding to the runoff water migration path includes:

[0019] Determining all water migration paths corresponding to the soil layer, and constructing a water migration function corresponding to each of the water migration paths;

[0020] According to the relationship between the melt water quality parameter and the water migrated in each water migration path of the soil layer, and the water migration function corresponding to each water migration path, a melt water quality parameter migration function corresponding to each water migration path is constructed.

[0021] In one embodiment, the water migration path includes a surface migration path and a soil migration path, and the method further includes:

[0022] constructing a relationship between the meltwater quality parameter and the water migrated in the surface migration path based on the thickness of the surface water;

[0023] Based on the soil moisture content and the thickness of the soil layer, a relationship between the meltwater quality parameter and the water migrated in the soil migration path is constructed.

[0024] In one embodiment, the surface migration path includes a surface runoff migration path and an infiltration migration path, and the soil migration path includes at least one of a soil runoff migration path, an evapotranspiration migration path, a soil longitudinal migration path, and a phase change migration path.

[0025] In a second aspect, the present application also provides a device for quantitatively analyzing permafrost meltwater runoff based on a distributed hydrological model. The device comprises:

[0026] A first construction module is used to divide the soil in the target area into at least one soil layer and construct a solid ice mass parameter corresponding to each soil layer;

[0027] a second construction module for determining, for any of the soil layers, a water migration path corresponding to the soil layer based on the location of the soil layer, and constructing a meltwater mass parameter migration function corresponding to each of the water migration paths based on a conversion relationship between solid ice and meltwater in the soil layer and a mass parameter of the solid ice corresponding to the soil layer; the water migration path includes at least a runoff water migration path;

[0028] A third construction module is configured to construct a target distributed hydrological model corresponding to the target area based on each meltwater quality parameter migration function;

[0029] A simulation module is used to simulate the water cycle process of the target area through the target distributed hydrological model to obtain a simulation result, and determine the permafrost meltwater runoff in the target area based on the output value of the meltwater quality parameter migration function corresponding to the runoff moisture migration path in the simulation result.

[0030] In one embodiment, the first building block is further configured to:

[0031] For any of the soil layers, an ice content correlation parameter corresponding to the soil layer is determined, a soil ice mass of the soil layer is constructed based on the ice content correlation parameter, and the soil ice mass corresponding to the soil layer at a target time is used as a solid ice mass parameter corresponding to the soil layer.

[0032] In one embodiment, the first building block is further configured to:

[0033] In the case where the soil layer includes permafrost, the soil ice mass corresponding to a first target time is used as the solid ice mass parameter, where the first target time is the time at which the soil thawing depth is the deepest among all times of the year;

[0034] In the case where the soil layer includes seasonal frozen soil, the soil ice mass at a second target time is used as the solid ice mass parameter, where the second target time is the time at which the soil freezing depth is the deepest among various times of the year.

[0035] In one embodiment, the apparatus further comprises:

[0036] An acquisition module is configured to acquire the surface soil temperature from a current simulation result of the target distributed hydrological model during the process of the target distributed hydrological model simulating the water cycle process of the target area;

[0037] The determination module is configured to determine that the second target time has been reached when the surface soil temperature indicates that the soil has begun to melt, and to determine that the first target time has been reached when the surface soil temperature indicates that the soil has begun to freeze.

[0038] In one embodiment, the second building block is further configured to:

[0039] Determining all water migration paths corresponding to the soil layer, and constructing a water migration function corresponding to each of the water migration paths;

[0040] According to the relationship between the melt water quality parameter and the water migrated in each water migration path of the soil layer, and the water migration function corresponding to each water migration path, a melt water quality parameter migration function corresponding to each water migration path is constructed.

[0041] In one embodiment, the water migration path includes a surface migration path and a soil migration path, and the device further includes:

[0042] a fourth building block for building a relationship between the meltwater quality parameter and the water migrating in the surface migration path based on the thickness of the surface water;

[0043] The fifth construction module is used to construct a relationship between the meltwater quality parameter and the water migrated in the soil migration path based on the soil moisture content and the thickness of the soil layer.

[0044] In one embodiment, the surface migration path includes a surface runoff migration path and an infiltration migration path, and the soil migration path includes at least one of a soil runoff migration path, an evapotranspiration migration path, a soil longitudinal migration path, and a phase change migration path.

[0045] In a third aspect, the present application further provides a computer device, wherein the computer device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements any of the above methods when executing the computer program.

[0046] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements any of the above methods when executed by a processor.

[0047] In a fifth aspect, the present application further provides a computer program product, comprising a computer program, which implements any of the above methods when executed by a processor.

[0048] The above-mentioned method and device for quantitative analysis of permafrost meltwater runoff based on a distributed hydrological model constructs solid ice mass parameters to describe the solid ice in the soil layer, and then determines the water migration path of the soil layer and the conversion relationship between the solid ice mass parameter and the meltwater quality parameter for each soil layer, and constructs a meltwater quality parameter migration function corresponding to each water migration path to describe the loss of the solid ice quality parameter during the water cycle. Then, based on each of the meltwater quality parameter migration functions, a target distributed hydrological model corresponding to the target area is constructed, and the water cycle process is simulated by the target distributed hydrological model. Based on the output value calculated by the meltwater quality parameter migration function for the runoff water migration path of the target distributed hydrological model, the contribution of the solid ice in the permafrost in the target area to the runoff in the target area after melting is determined. The embodiment of the present application calculates the permafrost meltwater runoff through model simulation, which can adapt to various watershed ranges and reduce the calculation cost of the permafrost meltwater runoff. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 1 is a flow chart of a method for quantitatively analyzing frozen soil ice meltwater runoff based on a distributed hydrological model in one embodiment;

[0050] Figure 2 Schematic diagram of a process for quantitative analysis of permafrost meltwater runoff based on a distributed hydrological model in another embodiment;

[0051] Figure 3 A schematic diagram of the contribution of permafrost meltwater runoff to runoff volume for permafrost and seasonally frozen soil in one embodiment;

[0052] Figure 4 1 is a structural block diagram of a device for quantitatively analyzing frozen soil ice meltwater runoff based on a distributed hydrological model in one embodiment;

[0053] Figure 5 FIG. 1 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0055] In one embodiment, Figure 1 As shown, a method for quantitative analysis of permafrost meltwater runoff based on a distributed hydrological model is provided. This embodiment uses the method applied to a server as an example. It is understood that the method can also be applied to a terminal, or to a system including a terminal and a server, and implemented through interaction between the terminal and the server. In this embodiment, the method includes the following steps:

[0056] Step 102: Divide the soil in the target area into at least one soil layer, and construct solid ice mass parameters corresponding to each soil layer.

[0057] In the embodiment of the present application, the target area is the area where the permafrost meltwater runoff needs to be simulated. The soil in the target area can be divided into multiple layers according to the properties of the soil, so that the properties of the soil in each layer are similar to improve the calculation accuracy. The thickness of each soil layer can be different. For example, because the water cycle process in the surface soil is more complex than that in the deeper soil, the depth of the soil layer closer to the surface soil can be made shallower when dividing the soil layers to more accurately simulate the water cycle process in the surface soil.

[0058] The solid ice mass parameter can be any parameter used to describe the mass of solid ice in the soil layer to be studied. The solid ice mass parameter can be set based on the relationship between the solid ice and soil ice mass to be studied.

[0059] For example, if one wants to study the contribution of soil ice on a specific date to runoff during the subsequent water cycle, the mass of soil ice on that specific date can be used as the solid ice mass parameter. Furthermore, during the operation of the target distributed hydrological model, the contribution of the meltwater mass parameter to runoff can be determined by converting the solid ice mass parameter to the meltwater mass parameter.

[0060] Soil ice mass can be estimated by sampling the soil in the target area, or by obtaining ice content-related parameters related to soil ice mass and constructing a mathematical model to describe the relationship between these parameters and soil ice mass. For example, ice content-related parameters may include the target area's temperature, soil moisture, and radiation conditions.

[0061] The embodiments of the present application do not limit the parameters selected as ice content-related parameters. The parameters can be specifically determined based on which input parameters of the target distributed hydrological model can be collected for the target area, and which parameters can be calculated by the target distributed hydrological model based on the input parameters. For example, if the target area's average daily precipitation, average daily temperature, downward shortwave and longwave solar radiation, and multi-year average ground temperature can be collected as input parameters for the target distributed hydrological model, and the target distributed hydrological model can further calculate soil ice mass based on these input parameters using a thermodynamic model, the target area's average daily precipitation, average daily temperature, downward shortwave and longwave solar radiation, and multi-year average ground temperature can be used as ice content-related parameters.

[0062] The embodiments of the present application also do not specifically limit how to calculate the soil ice mass based on the ice content correlation parameter. For example, the soil in the target area can be sampled to obtain the distribution of solid ice in the soil layer, and then the specific value of the ice content correlation parameter in the target area can be collected. The correlation relationship between the ice content correlation parameter and the soil ice mass can be obtained through methods such as function fitting, and the soil ice mass can be constructed through this correlation relationship.

[0063] In one embodiment, constructing solid ice mass parameters corresponding to each soil layer includes:

[0064] For any of the soil layers, an ice content correlation parameter corresponding to the soil layer is determined, a soil ice mass of the soil layer is constructed based on the ice content correlation parameter, and the soil ice mass corresponding to the soil layer at a target time is used as a solid ice mass parameter corresponding to the soil layer.

[0065] In the embodiment of the present application, the ice content-related parameters corresponding to each soil layer can be the same or different. For example, for shallower soil layers, it may be determined that surface temperature and radiation conditions are more strongly correlated with soil ice mass, and therefore surface temperature and radiation conditions can be used as ice content-related parameters. For deeper soil layers, it may be determined that the daily average ground temperature is more strongly correlated with the solid ice mass parameter, and therefore the daily average low temperature can be used as the ice content-related parameter.

[0066] After determining the ice content correlation parameters for each soil layer, the soil ice mass of the soil layer can be constructed based on the ice content correlation parameters. The soil ice mass at the target time can then be set as the solid ice mass parameter. The target time refers to the time of day to be studied. If there are multiple target times, there will also be multiple solid ice mass parameters. The permafrost meltwater runoff calculated based on each solid ice mass parameter can reflect the contribution of solid ice to the runoff at each target time.

[0067] It should be further explained that in order to make the solid ice mass parameter have length units in the dimension, which is convenient for the subsequent runoff calculation, the ice content correlation parameter can also be used to first construct the volume ratio of ice in the soil layer, and then the soil ice mass can be further constructed using the following formula (1):

[0068] Formula (1)

[0069] in, refers to the soil ice mass of the i-th soil layer at the target time t, is the volume ratio of ice in the i-th soil layer at the target time t (hereinafter referred to as soil ice content), is the thickness of the i-th soil layer, is the density of ice.

[0070] In one embodiment, the soil ice mass corresponding to the soil layer at the target time is used as the solid ice mass parameter corresponding to the soil layer, including:

[0071] In the case where the soil layer includes permafrost, the soil ice mass corresponding to the first target time is used as the solid ice mass parameter, and the first target time is the time at which the soil thawing depth is the deepest among all times of the year;

[0072] In the case where the soil layer includes seasonal frozen soil, the soil ice mass at a second target time is used as the solid ice mass parameter. The second target time is the time at which the corresponding soil freezing depth is the deepest among various times of the year.

[0073] In an embodiment of the present application, solid ice mass parameters corresponding to permafrost and seasonal frozen soil in the soil layer can be constructed respectively, so that a meltwater quality parameter migration function can be subsequently constructed based on the solid ice mass parameters. After obtaining the output value of the meltwater quality parameter migration function through the simulation results of the target distributed hydrological model, the portion of the permafrost and the portion of the seasonal frozen soil in the output value can be calculated using the solid ice mass parameters corresponding to the permafrost and seasonal frozen soil respectively, so as to respectively determine the contribution of permafrost and seasonal frozen soil to the permafrost ice meltwater runoff.

[0074] The soil ice mass at the moment when the soil melting depth is the deepest (the first target moment) at each time of the year can be used as the solid ice mass parameter of permafrost. At this moment, almost all the ice in the seasonally frozen soil has melted, and almost all the solid ice in the soil comes from permafrost.

[0075] The soil ice mass at the moment when the soil freezing depth is deepest (the second target moment) at each moment of the year can also be used as the solid ice mass parameter of seasonal frozen soil. At this moment, the seasonal frozen soil is almost completely frozen and the ice content in the seasonal frozen soil reaches the maximum.

[0076] If a soil layer contains both permafrost and seasonally frozen soil, two solid ice mass parameters can be constructed based on the soil ice mass at the first target time and the soil ice mass at the second target time, respectively. Considering that the ice content in permafrost generally remains stable throughout the year, the permafrost ice meltwater runoff calculated based on the solid ice mass parameter constructed based on the soil ice mass at the second target time and the permafrost ice meltwater runoff calculated based on the solid ice mass parameter constructed based on the soil ice mass at the first target time can be used as the contribution of seasonal frozen soil to the permafrost ice meltwater runoff.

[0077] The first target time and the second target time can be pre-set, or can be determined in real time during the simulation of the target distributed hydrological model. For example, September 1st can be pre-set as the first target time and May 1st as the second target time. When the first target time and the second target time are determined in real time during the simulation of the target distributed hydrological model, the determination method is as follows:

[0078] In the process of simulating the water cycle process of the target area by the target distributed hydrological model, the surface soil temperature is obtained from the current simulation result of the target distributed hydrological model;

[0079] When the surface soil temperature indicates that the soil is beginning to melt, the second target time is determined to have been reached, and when the surface soil temperature indicates that the soil is beginning to freeze, the first target time is determined to have been reached.

[0080] In the embodiments of the present application, the target distributed hydrological model typically simulates the water cycle using a predetermined simulation step length. After each simulation step, the target distributed hydrological model can determine the surface soil temperature in the simulation results of that simulation. Based on the surface soil temperature, it can be determined whether the soil has begun to melt or freeze, thereby determining whether the first target time or the second target time has been reached.

[0081] The present embodiment does not limit how to determine whether the soil has begun to melt or freeze based on the surface soil temperature. For example, soil melting can be determined when the surface soil temperature in multiple consecutive simulation results is greater than 0. This is the time at which the soil freezing depth is deepest at any time of the year. Therefore, the time simulated by the target distributed hydrological model at this time can be used as the second target time, and the specific value of the soil ice mass in the simulation results can be obtained. The specific value of the solid ice mass parameter can then be calculated based on the specific soil ice mass value. The water cycle process can then be simulated based on this value to obtain the permafrost ice meltwater runoff contributed by seasonal frozen soil.

[0082] Similarly, when the surface soil temperature in multiple consecutive simulation results is less than or equal to 0, it can be determined that the soil has begun to freeze. This is the time when the soil melting depth is the deepest at various times of the year. The time simulated by the target distributed hydrological model at this time can be used as the first target time to simulate the permafrost ice meltwater runoff contributed by permafrost.

[0083] Step 104: For any soil layer, determine the water migration path corresponding to the soil layer based on its location, and construct a meltwater mass parameter migration function corresponding to each water migration path based on the conversion relationship between solid ice and meltwater in the soil layer and the solid ice mass parameter corresponding to the soil layer; the water migration path includes at least the runoff water migration path.

[0084] In an embodiment of the present application, the moisture migration path of the soil layer can be determined based on the location of the soil layer. For example, when the soil layer is located in the surface soil, it can be determined that the moisture in the soil layer will be lost through runoff, vegetation transpiration, evaporation, and water exchange with the next soil layer, and will be replenished through water exchange with adjacent soil layers or surface water. Therefore, it can be determined that the moisture migration path corresponding to the soil layer at least includes runoff, vegetation transpiration, evaporation, and water exchange with adjacent soil layers or surface water. For other soil layers, a similar method can also be used to determine the moisture migration paths of other soil layers. Among these moisture migration paths, the path that guides runoff is the runoff moisture migration path. The runoff moisture migration path may include a surface runoff migration path, a soil runoff migration path, an underground runoff migration path, and the like.

[0085] The conversion relationship between solid ice and melted water can be determined based on heat conduction models and other methods. For example, for each soil layer, the amount of heat that the soil layer can receive can be determined based on its location. The phase change can then be calculated based on the heat received by the soil layer to obtain the conversion relationship between solid ice and melted water.

[0086] Based on the conversion relationship between solid ice and meltwater and the solid ice mass parameters, the meltwater mass parameters corresponding to the soil layer can be calculated. Based on the specific water migration paths through which all the water in the soil layer migrates and the proportion of meltwater in the water that migrates through each water migration path, a meltwater mass parameter migration function corresponding to each water migration path can be constructed. The specific steps are as follows:

[0087] Determine all water migration paths corresponding to the soil layer and construct the water migration function corresponding to each water migration path;

[0088] According to the relationship between meltwater quality parameters and the water migrated in the soil layer in each water migration path, as well as the water migration function corresponding to each water migration path, the meltwater quality parameter migration function corresponding to each water migration path is constructed.

[0089] In an embodiment of the present application, the moisture migration function corresponding to each moisture migration path can be constructed through a corresponding mathematical model. For example, for vegetation transpiration, the relationship between meteorological parameters such as temperature, light, wind speed, humidity, and vegetation characteristic parameters such as leaf area index and biomass and vegetation transpiration can be determined through the existing empirical model of vegetation transpiration, and then the moisture migration function can be constructed through this relationship.

[0090] The relationship between the meltwater quality parameter and the amount of water migrated by the soil layer along each water migration path can be characterized by the ratio between the meltwater quality parameter and the corresponding water quality parameter of the soil layer along that water migration path. The dimensions of the water quality parameter should be the same as those of the solid ice quality parameter and the meltwater quality parameter, so that the ratio between the meltwater quality parameter and the corresponding water quality parameter of the soil layer can represent the proportion of meltwater in the total water content of the soil layer.

[0091] In one embodiment, the water migration path includes a surface migration path and a soil migration path. The relationship between the meltwater quality parameter and the water content in each migration path can be constructed by referring to the following steps:

[0092] Constructing relationships between meltwater quality parameters and water migrated along surface migration pathways based on surface water thickness;

[0093] Based on soil moisture content and soil layer thickness, the relationship between meltwater quality parameters and water migrated along the soil migration pathway is constructed.

[0094] In the embodiment of the present application, the surface migration path includes the surface runoff migration path and the infiltration migration path. The proportion of melt water in the water migrated through the surface runoff migration path and the infiltration migration path can be determined according to the thickness of the surface water, as shown in Formula (2):

[0095] Formula (2)

[0096] in, Refers to the proportion of meltwater in the total water in the surface runoff migration path. The meltwater quality parameter corresponding to the surface water can be obtained according to the ratio of the surface water to the total water content of the soil layer where it is located and the product of the total amount of the meltwater quality parameter in the soil layer where it is located. is the thickness of surface water, is the density of water.

[0097] The meltwater quality parameter migration function corresponding to the surface runoff migration path can be further constructed using formula (3):

[0098] Formula (3)

[0099] in, is the meltwater quality parameter that migrates through the surface runoff migration path, is the surface runoff.

[0100] Soil migration pathways include at least one of the following: soil runoff migration pathways, evapotranspiration migration pathways, soil longitudinal migration pathways, and phase change migration pathways. The evapotranspiration migration pathway represents water that migrates through transpiration or evaporation from vegetation, the longitudinal soil migration pathway represents water exchanged between the soil layer and the soil layer above or below it, and the phase change migration pathway represents water that migrates through freezing or thawing. The relationship between meltwater quality parameters and total water in the soil migration pathway can be calculated using Formula (IV):

[0101] Formula (4)

[0102] in, It refers to the proportion of melt water in the i-th soil layer to the total water content. is the meltwater quality parameter in the i-th soil layer, is the soil moisture content in the i-th soil layer, is the thickness of the i-th soil layer, is the density of water.

[0103] The meltwater quality parameter migration function corresponding to the soil migration path can be further constructed using formula (5):

[0104] Formula (5)

[0105] in, is the meltwater quality parameter of the i-th soil layer through the soil migration path, is the soil runoff, that is, the water migration function corresponding to the soil runoff migration path, is the water output from the i-th soil layer to the i+1-th soil layer, is the water output from the i-1th soil layer to the i-th soil layer, The moisture migration function corresponding to the soil longitudinal migration path, is the evapotranspiration, that is, the water migration function corresponding to the evapotranspiration migration path, is the moisture migration function corresponding to the phase change migration path.

[0106] It can be further written as formula (6):

[0107] Formula (6)

[0108] in, is the total mass of water that undergoes phase change. When the phase changes to freezing, liquid water turns into solid ice, causing water loss. When the phase changes to melting, solid ice turns into liquid water, causing water gain. It is calculated based on the ratio of the product of the solid ice mass parameter currently remaining in the i-th soil layer (i.e., the solid ice mass parameter not converted into meltwater mass parameter) and the soil ice content, the thickness of the soil layer, and the density of the ice, as shown in Formula (VII):

[0109] Formula (7)

[0110] in, is the current solid ice mass parameter, is the soil ice content of the i-th soil layer, is the thickness of the i-th soil layer, is the density of ice.

[0111] Step 106 : constructing a target distributed hydrological model corresponding to the target area based on the meltwater quality parameter migration function.

[0112] In the embodiment of the present application, based on the principle of conservation of mass, for the entire target area, the sum of the output values ​​of all meltwater quality parameter migration functions of all soil layers and the sum of the meltwater quality parameters and solid ice quality parameters remaining in all soil layers should be equal to the sum of the solid ice quality parameters originally constructed for all soil layers. A target distributed hydrological model for simulating the water cycle process can be constructed based on this constraint and the meltwater quality parameter migration function of each soil layer. Taking the meltwater quality parameter migration function including the contents of formula (2) to formula (7) in the aforementioned embodiment as an example, the process of constructing a target distributed hydrological model for simulating the water cycle process is: first determine which input parameters can be obtained for the target area, and then construct a target distributed hydrological model that can calculate the aforementioned formulas (2) to (7) based on the input parameters. 、 、 、 、 、 、 、 、 A mathematical model that takes into account various unknown quantities and the conservation of energy and mass in the target area is developed to obtain the target distributed hydrological model.

[0113] Alternatively, a distributed hydrological model that has been constructed for the target area can be obtained, and the meltwater quality parameter migration function of each soil layer and the constructed distributed hydrological model can be integrated to obtain the target distributed hydrological model, so that after the target distributed hydrological model is run according to the logic of the original distributed hydrological model to obtain the simulation results, the unknown quantities required in the aforementioned formulas can be obtained from the simulation results, and the output values ​​of each meltwater quality parameter migration function can be calculated.

[0114] Step 108: The water cycle process of the target area is simulated by the target distributed hydrological model to obtain simulation results, and the permafrost meltwater runoff of the target area is determined based on the output value of the meltwater quality parameter migration function corresponding to the runoff water migration path in the simulation results.

[0115] In this embodiment of the present application, the target distributed hydrological model simulates the water cycle in the target region to obtain simulation results. These simulation results refer to various parameters related to the water cycle in the target region and the output values ​​of various meltwater quality parameter transfer functions. The output values ​​of the meltwater quality parameter transfer functions corresponding to the runoff water migration paths (including surface runoff migration paths and soil runoff migration paths) in each soil layer are summed to obtain the permafrost meltwater runoff in the target region.

[0116] The following describes the above process through a practical example. Figure 2 FIG. 1 is a flow chart of a method for quantitatively analyzing frozen ground ice meltwater runoff based on a distributed hydrological model in one embodiment, including:

[0117] S1, construct a distributed hydrological model.

[0118] In the embodiment of the present application, before tracking the solid ice in the permafrost, a distributed hydrological model that can describe the water cycle process in the target area is first constructed. This application selects the source area of ​​the Yangtze River as the target area.

[0119] The parameters required to build a distributed hydrological model can be found in Table 1:

[0120] Table 1

[0121]

[0122] The function of the above parameters is to construct a distributed hydrological model describing the water cycle process based on meteorological data and underlying surface data. The input of the distributed hydrological model is the data with time resolution in the above table, and the output is the various parameters involved in the water cycle process, such as the runoff of each river in the target area, soil moisture content, surface water thickness, etc. The model is then regularly calibrated using verification data. The embodiments of the present application do not limit how to construct a distributed hydrological model. Models that can simulate soil water movement, soil freeze-thaw, evapotranspiration, surface runoff, soil runoff and groundwater runoff or parts of these processes are applicable to the embodiments of the present application.

[0123] In the distributed hydrological model finally constructed in the embodiment of the present application, the target area is divided into multiple grid units, and each grid unit is divided into multiple soil layers for calculation. The model divides the soil from 0 to 49 meters into 39 layers, and the thickness of each layer increases with depth. The energy balance method is adopted in the model, and the net radiation of the surface and the geothermal flux are used as boundary conditions to calculate the soil heat conduction, convection and soil moisture phase change. The initial soil temperature of the model is calculated based on the multi-year average ground temperature obtained based on the measured boreholes in existing studies, combined with the actual observed soil profile temperature. The initial soil ice content of the model is given by the data provided in existing studies.

[0124] S2, calculate the solid ice mass parameters of permafrost and seasonally frozen soil.

[0125] In this embodiment, since permafrost generally exists in deeper soil layers and receives less external replenishment, the solid ice mass parameters for permafrost can be calculated in the first year of the simulation and then no longer updated. The calculation method is to sample the soil ice content in the target area on September 1st, use the soil ice content of each sampled soil layer as the soil ice content of the i-th soil layer at a specific time in the aforementioned formula (1), and then calculate the solid ice mass parameters for permafrost using formula (1).

[0126] For seasonally frozen soil, the solid ice mass parameter must be updated every year of model operation to reflect the external supply of seasonally frozen soil. Before the model begins, the soil ice content in the target area is sampled on January 1st. The soil ice content of each sampled soil layer is used as the soil ice content of the i-th soil layer at a specific time in the aforementioned formula (1). The solid ice mass parameter for seasonally frozen soil is then calculated using formula (1). After the model begins, the solid ice mass parameter is updated on the following day: During the model operation, the average daily surface soil temperature for each grid within the model is calculated. If the average daily temperature reaches above 0°C for two consecutive days throughout the year, indicating that the soil has begun to melt and the freezing depth has reached its maximum, the solid ice mass parameter for all soil layers within the grid is updated using formula (1) on that day. For grids where the temperature is below 0°C year-round, the solid ice mass parameter for all soil layers within the grid is updated using formula (1) on June 1st of each year.

[0127] S3, warm up the model until the solid ice mass parameters of permafrost are stable.

[0128] In the embodiment of the present application, the distributed hydrological model is run, and during the run, the solid ice mass parameter in the permafrost is continuously calculated according to formula (1). When the solid ice mass parameter reaches stability, the model is considered to have completed preheating.

[0129] S4, construct the meltwater quality parameter migration function and integrate the meltwater quality parameter migration function with the distributed hydrological model.

[0130] In an embodiment of the present application, a meltwater quality parameter migration function is constructed with reference to the aforementioned embodiment, and the meltwater quality parameter migration function and the distributed hydrological model are integrated so that the distributed hydrological model can synchronously output the output value of each meltwater quality parameter migration function during operation.

[0131] S5, statistically analyzing the output values ​​of the meltwater quality parameter migration function corresponding to the runoff water migration path to determine the permafrost meltwater runoff in the target area.

[0132] In the embodiment of the present application, the output values ​​of the meltwater quality parameter migration function corresponding to the runoff moisture migration paths of all soil layers in all grids are added together to obtain the permafrost meltwater runoff in the target area.

[0133] Using the above method, the runoff process in the source region of the Yangtze River in 1991 was simulated, and the contribution of solid ice meltwater in permafrost and seasonally frozen soil to runoff in the source region of the Yangtze River in 1991 was calculated. The total runoff in the source region of the Yangtze River in 1991 was 77.9 mm. The contribution of permafrost and seasonally frozen soil to runoff was 1.4 mm and 30.0 mm, respectively. The contribution of solid ice meltwater in permafrost and seasonally frozen soil to runoff was 1.8% and 38.5%, respectively. Its distribution within the year is as follows: Figure 3 As shown in Figure 2, it can be seen that the contribution of meltwater from permafrost and seasonally frozen soil to runoff is mainly distributed from July to October.

[0134] The embodiment of the present application provides a quantitative analysis method for permafrost meltwater runoff based on a distributed hydrological model. The method constructs solid ice mass parameters to describe the solid ice in the soil layer, and then determines the moisture migration path of the soil layer and the conversion relationship between the solid ice mass parameter and the meltwater quality parameter for each soil layer. The meltwater quality parameter migration function corresponding to each moisture migration path is constructed to describe the loss of the solid ice quality parameter during the water cycle. Based on each meltwater quality parameter migration function, a target distributed hydrological model corresponding to the target area is constructed. The water cycle process is simulated using the target distributed hydrological model. Based on the output value calculated by the meltwater quality parameter migration function for the runoff moisture migration path of the target distributed hydrological model, the contribution of the solid ice in the permafrost in the target area to the runoff in the target area after melting is determined. The embodiment of the present application calculates the permafrost meltwater runoff by model simulation, which can be adapted to various watershed ranges and can reduce the calculation cost of the permafrost meltwater runoff.

[0135] It should be understood that, although the various steps in the flowcharts involved in the various embodiments described above are displayed in sequence according to the instructions of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the various embodiments described above can include multiple steps or multiple stages, and these steps or stages are not necessarily executed and completed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0136] Based on the same inventive concept, embodiments of the present application also provide a distributed hydrological model-based permafrost meltwater runoff quantitative analysis device for implementing the aforementioned distributed hydrological model-based permafrost meltwater runoff quantitative analysis method. The solution provided by this device is similar to the solution described in the aforementioned method. Therefore, the specific limitations of one or more embodiments of the distributed hydrological model-based permafrost meltwater runoff quantitative analysis device provided below can be found in the aforementioned definitions of the distributed hydrological model-based permafrost meltwater runoff quantitative analysis method and will not be further elaborated here.

[0137] In one embodiment, Figure 4 As shown, a device 400 for quantitative analysis of permafrost ice meltwater runoff based on a distributed hydrological model is provided, comprising: a first construction module 402, a second construction module 404, a third construction module 406, and a simulation module 408, wherein:

[0138] A first constructing module 402 is configured to divide the soil in the target area into at least one soil layer and construct a solid ice mass parameter corresponding to each soil layer;

[0139] A second construction module 404 is configured to determine, for each soil layer, a water migration path corresponding to the soil layer based on the location of the soil layer, and construct a meltwater mass parameter migration function corresponding to each water migration path based on a conversion relationship between solid ice and meltwater in the soil layer and a mass parameter of the solid ice corresponding to the soil layer; the water migration path includes at least a runoff water migration path;

[0140] A third construction module 406 is configured to construct a target distributed hydrological model corresponding to the target area based on each meltwater quality parameter migration function;

[0141] The simulation module 408 is used to simulate the water cycle process of the target area through the target distributed hydrological model to obtain a simulation result, and determine the permafrost meltwater runoff in the target area based on the output value of the meltwater quality parameter migration function corresponding to the runoff moisture migration path in the simulation result.

[0142] In one embodiment, the first building module 402 is further configured to:

[0143] For any of the soil layers, an ice content correlation parameter corresponding to the soil layer is determined, a soil ice mass of the soil layer is constructed based on the ice content correlation parameter, and the soil ice mass corresponding to the soil layer at a target time is used as a solid ice mass parameter corresponding to the soil layer.

[0144] In one embodiment, the first building module 402 is further configured to:

[0145] In the case where the soil layer includes permafrost, the soil ice mass corresponding to a first target time is used as the solid ice mass parameter, where the first target time is the time at which the soil thawing depth is the deepest among all times of the year;

[0146] In the case where the soil layer includes seasonal frozen soil, the soil ice mass at a second target time is used as the solid ice mass parameter, where the second target time is the time at which the soil freezing depth is the deepest among various times of the year.

[0147] In one embodiment, the apparatus further comprises:

[0148] An acquisition module is configured to acquire the surface soil temperature from a current simulation result of the target distributed hydrological model during the process of the target distributed hydrological model simulating the water cycle process of the target area;

[0149] The determination module is configured to determine that the second target time has been reached when the surface soil temperature indicates that the soil has begun to melt, and to determine that the first target time has been reached when the surface soil temperature indicates that the soil has begun to freeze.

[0150] In one embodiment, the second building module 404 is further configured to:

[0151] Determining all water migration paths corresponding to the soil layer, and constructing a water migration function corresponding to each of the water migration paths;

[0152] According to the relationship between the melt water quality parameter and the water migrated in each water migration path of the soil layer, and the water migration function corresponding to each water migration path, a melt water quality parameter migration function corresponding to each water migration path is constructed.

[0153] In one embodiment, the water migration path includes a surface migration path and a soil migration path, and the device further includes:

[0154] a fourth building block for building a relationship between the meltwater quality parameter and the water migrating in the surface migration path based on the thickness of the surface water;

[0155] The fifth construction module is used to construct a relationship between the meltwater quality parameter and the water migrated in the soil migration path based on the soil moisture content and the thickness of the soil layer.

[0156] In one embodiment, the surface migration path includes a surface runoff migration path and an infiltration migration path, and the soil migration path includes at least one of a soil runoff migration path, an evapotranspiration migration path, a soil longitudinal migration path, and a phase change migration path.

[0157] Each module in the above-mentioned apparatus may be implemented in whole or in part by software, hardware, or a combination thereof. Each module may be embedded in or independent of a processor in a computer device in the form of hardware, or may be stored in a memory in the computer device in the form of software, so that the processor can call and execute the corresponding operations of each module.

[0158] In one embodiment, a computer device is provided. The computer device may be a server, and its internal structure diagram may be as follows: Figure 5 As shown. The computer device includes a processor, memory, and a network interface connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external terminal via a network connection. When executed by the processor, the computer program implements a method for quantitative analysis of permafrost meltwater runoff based on a distributed hydrological model.

[0159] Those skilled in the art will understand that Figure 5 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0160] In one embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program, and the processor implements the steps in the above method embodiments when executing the computer program.

[0161] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0162] In one embodiment, a computer program product is provided, including a computer program, which implements the steps in the above method embodiments when executed by a processor.

[0163] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0164] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the above-mentioned embodiments. In particular, any reference to memory, database, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The databases involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, distributed databases based on blockchains. The processors involved in the various embodiments provided herein may be, but are not limited to, general-purpose processors, central processing units (CPUs), graphics processing units (GPUs), digital signal processors (DSPs), programmable logic devices (PLDs), data processing logic devices based on quantum computing, and the like.

[0165] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0166] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A quantitative analysis method for permafrost meltwater runoff based on a distributed hydrological model, characterized in that: The method comprises: Dividing the soil in the target area into at least one soil layer, and constructing a solid ice mass parameter corresponding to each soil layer; For any of the soil layers, a water migration path corresponding to the soil layer is determined based on the location of the soil layer, and a meltwater mass parameter migration function corresponding to each of the water migration paths is constructed based on the conversion relationship between solid ice and meltwater in the soil layer and the solid ice mass parameter corresponding to the soil layer; the water migration path includes at least a runoff water migration path; Constructing a target distributed hydrological model corresponding to the target area based on each meltwater quality parameter migration function; The water cycle process of the target area is simulated by the target distributed hydrological model to obtain a simulation result, and the permafrost meltwater runoff of the target area is determined based on the output value of the meltwater quality parameter migration function corresponding to the runoff moisture migration path in the simulation result.

2. The method according to claim 1, characterized in that The constructing of the solid ice mass parameters corresponding to each soil layer includes: For any of the soil layers, an ice content correlation parameter corresponding to the soil layer is determined, a soil ice mass of the soil layer is constructed based on the ice content correlation parameter, and the soil ice mass corresponding to the soil layer at a target time is used as a solid ice mass parameter corresponding to the soil layer.

3. The method according to claim 2, characterized in that The method of using the soil ice mass corresponding to the soil layer at the target time as the solid ice mass parameter corresponding to the soil layer includes: In the case where the soil layer includes permafrost, the soil ice mass corresponding to a first target time is used as the solid ice mass parameter, where the first target time is the time at which the soil thawing depth is the deepest among all times of the year; In the case where the soil layer includes seasonal frozen soil, the soil ice mass at a second target time is used as the solid ice mass parameter, where the second target time is the time at which the soil freezing depth is the deepest among various times of the year.

4. The method according to claim 3, characterized in that The method further comprises: During the process of simulating the water cycle process of the target area by the target distributed hydrological model, obtaining the surface soil temperature from the current simulation result of the target distributed hydrological model; When the surface soil temperature indicates that the soil begins to melt, it is determined that the second target time has been reached. When the surface soil temperature indicates that the soil begins to freeze, it is determined that the first target time has been reached.

5. The method according to claim 1, wherein The step of constructing a meltwater quality parameter migration function corresponding to the runoff water migration path includes: Determining all water migration paths corresponding to the soil layer, and constructing a water migration function corresponding to each of the water migration paths; According to the relationship between the melt water quality parameter and the water migrated in each water migration path of the soil layer, and the water migration function corresponding to each water migration path, a melt water quality parameter migration function corresponding to each water migration path is constructed.

6. The method according to claim 5, characterized in that The water migration path includes a surface migration path and a soil migration path, and the method further includes: constructing a relationship between the meltwater quality parameter and the water migrated in the surface migration path based on the thickness of the surface water; Based on the soil moisture content and the thickness of the soil layer, a relationship between the meltwater quality parameter and the water migrated in the soil migration path is constructed.

7. The method according to claim 6, characterized in that The surface migration path includes a surface runoff migration path and an infiltration migration path, and the soil migration path includes at least one of a soil runoff migration path, an evapotranspiration migration path, a soil longitudinal migration path, and a phase change migration path.

8. A device for quantitative analysis of frozen ground ice meltwater runoff based on a distributed hydrological model, characterized in that: The device comprises: A first construction module is used to divide the soil in the target area into at least one soil layer and construct a solid ice mass parameter corresponding to each soil layer; a second construction module for determining, for any of the soil layers, a water migration path corresponding to the soil layer based on the location of the soil layer, and constructing a meltwater mass parameter migration function corresponding to each of the water migration paths based on a conversion relationship between solid ice and meltwater in the soil layer and a mass parameter of the solid ice corresponding to the soil layer; the water migration path includes at least a runoff water migration path; A third construction module is configured to construct a target distributed hydrological model corresponding to the target area based on each meltwater quality parameter migration function; A simulation module is used to simulate the water cycle process of the target area through the target distributed hydrological model to obtain a simulation result, and determine the permafrost meltwater runoff in the target area based on the output value of the meltwater quality parameter migration function corresponding to the runoff moisture migration path in the simulation result.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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