Method and device for constructing radial rainfall model of tropical cyclone, storage medium and terminal

Abstract

This invention discloses a method, apparatus, storage medium, and terminal for constructing a tropical cyclone radial precipitation model. The method includes acquiring historical tropical cyclone precipitation rate data for an observation area and constructing historical radial precipitation rate curves; obtaining various curve structure characteristic parameter sets based on the historical radial precipitation rate curves; fitting expressions for radial precipitation peak value, radial precipitation peak radius, tropical cyclone precipitation center precipitation rate, and radial precipitation attenuation radius based on the parameter sets; constructing a radial precipitation attenuation factor based on the above expressions; and finally, introducing the parameter expressions and the radial precipitation attenuation factor into an R-CLIPER model to form a tropical cyclone radial precipitation model. This invention incorporates attenuation distance and precipitation attenuation into the construction process of the tropical cyclone radial precipitation model by constructing a radial precipitation attenuation factor, thereby significantly improving the ability of the constructed tropical cyclone radial precipitation model to characterize radial precipitation attenuation.

Description

Technical Field

[0001] This invention relates to the field of tropical cyclone precipitation modeling technology, and in particular to a method, apparatus, storage medium, and terminal for constructing a tropical cyclone radial precipitation model. Background Technology

[0002] Tropical cyclone precipitation has a complex structure. Generally, it is considered that, from the center outwards, typical tropical cyclone precipitation can be divided into three parts: the almost dry tropical cyclone center, the eyewall region, and the spiral rainbands. These rainbands can be further subdivided into inner and outer rainbands based on their distance from the cyclone center. Due to the complex structure and location of tropical cyclone rainbands, the radial precipitation curves of each tropical cyclone have their own characteristics. However, overall, the changes in the radial precipitation curves still follow a pattern, exhibiting a two-stage variation of first increasing and then decreasing radially.

[0003] Constructing a radial precipitation model for a tropical cyclone involves building its radial precipitation curve. This process addresses three key issues: first, determining the radial precipitation peak and its radius; second, characterizing the periphery of the tropical cyclone's precipitation, i.e., the radial precipitation attenuation radius; and third, the precipitation variation pattern on both sides of the radial precipitation peak, specifically the increasing pattern from the cyclone center to the peak and the attenuation pattern from that point to the radial precipitation attenuation radius. Characterizing the attenuation pattern of radial precipitation is the most challenging and crucial issue. From the radial precipitation peak radius outwards, the precipitation magnitude gradually decreases radially. The rate of attenuation depends on the radial precipitation attenuation distance and the difference in precipitation between the radial precipitation peak and the attenuation radius. The smaller the radial precipitation attenuation distance and the more significant the difference in precipitation, meaning a greater decrease in precipitation per unit distance, the faster the radial precipitation attenuation. In other words, the radial attenuation rate of a tropical cyclone is influenced by both the radial precipitation attenuation distance and the amount of precipitation attenuation.

[0004] However, existing parametric precipitation models do not fully consider the above factors when characterizing precipitation attenuation. For example, the HuRRDE (Hurricane Rainfall Rate and Distribution Estimator) model developed by FEMA in the United States considers the peak precipitation radius but ignores the precipitation attenuation radius when characterizing precipitation attenuation; the CAPRA (Central America Probabilistic Risk Assessment Program) model in Central America does not consider the radial precipitation attenuation distance at all; and the R-CLIPER (Tropical Cyclone Rainfall Climatology and Persistence Model) model developed by NOAA only describes the radial precipitation attenuation rate as an expression related to the radial precipitation attenuation radius. When simulating the radial precipitation curve of tropical cyclones in the Northwest Pacific, its characterization of radial precipitation attenuation from the peak precipitation radius of the tropical cyclone is not ideal. Summary of the Invention

[0005] The technical problem to be solved by the present invention is that the existing methods for constructing radial precipitation models of tropical cyclones do not fully consider the radial precipitation attenuation distance and precipitation attenuation amount, resulting in the constructed radial precipitation models of tropical cyclones being unsatisfactory in characterizing radial precipitation attenuation.

[0006] To address the aforementioned technical problems, this invention provides a method for constructing a tropical cyclone radial precipitation model, comprising:

[0007] Historical tropical cyclone precipitation rate data and historical maximum wind speed data within a preset time period are obtained in the observation area, and historical radial precipitation rate curves for multiple time points are constructed based on the historical tropical cyclone precipitation rate data;

[0008] For each historical radial precipitation rate curve, acquire the historical radial precipitation peak data, historical radial precipitation peak radius data, historical tropical cyclone precipitation center precipitation rate data, and historical radial precipitation attenuation radius data to form the historical radial precipitation peak data set, historical radial precipitation peak radius data set, historical tropical cyclone precipitation center precipitation rate data set, and historical radial precipitation attenuation radius data set, respectively.

[0009] Based on the historical maximum wind speed data and the historical radial precipitation peak data set, a radial precipitation peak value expression is fitted; based on the historical radial precipitation peak value data set and the historical radial precipitation peak radius data set, a radial precipitation peak radius expression is fitted; based on the historical radial precipitation peak value data set and the historical tropical cyclone precipitation center precipitation rate data set, a tropical cyclone precipitation center precipitation rate expression is fitted; and based on the historical radial precipitation peak value data set and the historical radial precipitation attenuation radius data set, a radial precipitation attenuation radius expression is fitted.

[0010] A radial precipitation attenuation factor is constructed based on the radial precipitation peak value expression, the radial precipitation peak radius expression, the tropical cyclone precipitation center precipitation rate expression, and the radial precipitation attenuation radius expression.

[0011] The radial precipitation peak expression, the radial precipitation peak radius expression, the tropical cyclone precipitation center precipitation rate expression, and the radial precipitation attenuation factor are introduced into the R-CLIPER model to form a tropical cyclone radial precipitation model.

[0012] Preferably, obtaining the historical radial precipitation attenuation radius data on the historical radial precipitation rate curve includes:

[0013] Obtain all the concave points on the historical radial precipitation rate curve, and select the concave points whose radial precipitation rate is less than a preset radial precipitation rate threshold from all the concave points as pre-concave points;

[0014] Obtain the precipitation difference ratio on both sides of all the prepared concave points, and select the first prepared concave point that meets the preset condition from all the prepared concave points in the order from the center of the tropical cyclone outward as the radial precipitation attenuation point. The distance of the radial precipitation attenuation point from the center of the corresponding tropical cyclone is the historical radial precipitation attenuation radius. The preset condition is that the precipitation difference ratio on both sides is less than the preset precipitation difference ratio threshold.

[0015] Preferably, if the radial precipitation peak value in the historical radial precipitation rate curve is greater than 10 mm / h, then the preset radial precipitation rate threshold is 1 mm / h; if the radial precipitation peak value in the historical radial precipitation rate curve is in the range of 2.5-10 mm / h, then the preset radial precipitation rate threshold is 0.5 mm / h; if the radial precipitation peak value in the historical radial precipitation rate curve is less than 2.5 mm / h, then the preset radial precipitation rate threshold is 0.3 mm / h.

[0016] If the radial precipitation peak value in the historical radial precipitation rate curve is greater than 2.5 mm / h, the preset precipitation difference ratio threshold is 5; if the radial precipitation peak value in the historical radial precipitation rate curve is less than 2.5 mm / h, the preset precipitation difference ratio threshold is 3.

[0017] Preferably, both the expression for the radial precipitation peak value and the expression for the radial precipitation peak radius are exponential relationships.

[0018] Preferably, both the expression for the precipitation rate at the center of the tropical cyclone and the expression for the radial precipitation attenuation radius are linear relationships.

[0019] Preferably, the radial precipitation attenuation factor is expressed as follows:

[0020]

[0021] Where RDF is the radial precipitation attenuation factor, A is a constant parameter, r is the distance from the center of the tropical cyclone, RMR is the radial precipitation peak radius, MRR is the radial precipitation peak, and RE is the radial precipitation attenuation radius.

[0022] Preferably, the expression for the tropical cyclone radial precipitation model is:

[0023]

[0024] Among them, RR sym The simulated radial precipitation rate curve is defined by RDF, where RDF is the radial precipitation attenuation factor, r is the distance from the center of the tropical cyclone, RMR is the radial precipitation peak radius, MRR is the radial precipitation peak value, and RE is the radial precipitation attenuation radius.

[0025] To address the aforementioned technical problems, this invention also provides a device for constructing a tropical cyclone radial precipitation model, comprising a historical data acquisition module, a historical parameter acquisition module, an expression fitting module, a radial precipitation attenuation factor construction module, and a model construction module.

[0026] The historical data acquisition module is used to acquire historical tropical cyclone precipitation rate data and historical maximum wind speed data within a preset time period in the observation area, and to construct historical radial precipitation rate curves for multiple time points based on the historical tropical cyclone precipitation rate data.

[0027] The historical parameter acquisition module is used to acquire the historical radial precipitation peak data, historical radial precipitation peak radius data, historical tropical cyclone precipitation center precipitation rate data, and historical radial precipitation attenuation radius data for each of the historical radial precipitation rate curves, respectively forming a historical radial precipitation peak data set, a historical radial precipitation peak radius data set, a historical tropical cyclone precipitation center precipitation rate data set, and a historical radial precipitation attenuation radius data set;

[0028] The expression fitting module is used to fit a radial precipitation peak expression based on the historical maximum wind speed data and the historical radial precipitation peak data set, to fit a radial precipitation peak radius expression based on the historical radial precipitation peak data set and the historical radial precipitation peak radius data set, to fit a tropical cyclone precipitation center precipitation rate expression based on the historical radial precipitation peak data set and the historical tropical cyclone precipitation center precipitation rate data set, and to fit a radial precipitation attenuation radius expression based on the historical radial precipitation peak data set and the historical radial precipitation attenuation radius data set.

[0029] The radial precipitation attenuation factor construction module is used to construct a radial precipitation attenuation factor based on the radial precipitation peak expression, the radial precipitation peak radius expression, the tropical cyclone precipitation center precipitation rate expression, and the radial precipitation attenuation radius expression.

[0030] The model building module is used to introduce the radial precipitation peak expression, the radial precipitation peak radius expression, the tropical cyclone precipitation center precipitation rate expression, and the radial precipitation attenuation factor into the R-CLIPER model to form a tropical cyclone radial precipitation model.

[0031] To address the aforementioned technical problems, the present invention also provides a storage medium storing a computer program that, when executed by a processor, implements the method for constructing a tropical cyclone radial precipitation model.

[0032] To address the aforementioned technical problems, the present invention also provides a terminal, comprising: a processor and a memory, wherein the memory and the processor are communicatively connected;

[0033] The memory is used to store computer programs, and the processor is used to execute the computer programs stored in the memory, so that the terminal executes the tropical cyclone radial precipitation model construction method.

[0034] Compared with the prior art, one or more embodiments of the above solutions may have the following advantages or beneficial effects:

[0035] The method for constructing a radial precipitation model of a tropical cyclone provided in this invention obtains a radial precipitation rate curve based on historical tropical cyclone precipitation rate data, and extracts multiple curve structure characteristic parameters from the radial precipitation rate curve. Then, based on the data of each curve structure characteristic parameter, expressions for each parameter are established / fitted. In the form of constructing a radial precipitation attenuation factor, the attenuation distance and precipitation attenuation are integrated into the construction process of the tropical cyclone radial precipitation model, so that the constructed tropical cyclone radial precipitation model has a significant improvement in characterizing the radial precipitation attenuation effect.

[0036] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, and drawings. Attached Figure Description

[0037] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0038] Figure 1 A flowchart illustrating the method for constructing a tropical cyclone radial precipitation model according to Embodiment 1 of the present invention is shown.

[0039] Figure 2 This diagram shows the radial precipitation rate curves obtained by simulating precipitation of tropical cyclones at six intensity levels in the Northwest Pacific using a tropical cyclone radial precipitation model in Embodiment 1 of the present invention.

[0040] Figure 3 This diagram illustrates the radial precipitation rate curves obtained by using the R-CLIPER model to simulate precipitation of tropical cyclones at six intensity levels in the Northwest Pacific in Embodiment 1 of the present invention.

[0041] Figure 4 A schematic diagram of the structure of the tropical cyclone radial precipitation model construction device according to Embodiment 2 of the present invention is shown;

[0042] Figure 5 A schematic diagram of the terminal structure of Embodiment 4 of the present invention is shown. Detailed Implementation

[0043] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings and examples, so that the process of how the present invention uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly. It should be noted that, as long as there is no conflict, the various embodiments and features in the various embodiments of the present invention can be combined with each other, and the resulting technical solutions are all within the protection scope of the present invention.

[0044] Maximum wind speed (MWS) refers to the "maximum average wind speed near the center of a tropical cyclone" in the national standard for tropical cyclone classification (GB / T 19201-2006). It is the indicator used in my country to classify the six intensity levels of tropical cyclones. The MWS data used in this article was downloaded from the "WND" indicator in the "CMA Tropical Cyclone Optimal Path Dataset" from the China Meteorological Administration's Tropical Cyclone Data Center. The tropical cyclone center refers to the latitude and longitude of the tropical cyclone center, and its source is the same as the MWS, namely the indicators "LAT" (latitude) and "LONG" (longitude) from the "CMA Tropical Cyclone Optimal Path Dataset" from the China Meteorological Administration's Tropical Cyclone Data Center.

[0045] The Tropical Cyclone Rainfall Climatology and Persistence Model (R-CLIPER) is a circularly symmetric precipitation structure parameter model for hurricane precipitation forecasting, jointly developed by NOAA's Hurricane Research Division and Geophysical Fluid Dynamics Laboratory. Based on station-observed precipitation data and TRMM satellite precipitation inversion products, the R-CLIPER model statistically analyzes the radial structure characteristics of precipitation and establishes a piecewise radial precipitation structure parameter model.

[0046] Example 1

[0047] To address the shortcomings of existing technologies, this invention provides a method for constructing a radial precipitation model for tropical cyclones.

[0048] Figure 1 This diagram illustrates the flowchart of the tropical cyclone radial precipitation model construction method according to Embodiment 1 of the present invention; see reference. Figure 1 The method for constructing a tropical cyclone radial precipitation model according to an embodiment of the present invention includes the following steps.

[0049] Step S101: Obtain historical tropical cyclone precipitation rate data and historical maximum wind speed data within a preset time period in the observation area, and construct historical radial precipitation rate curves for multiple time points based on the historical tropical cyclone precipitation rate data.

[0050] Specifically, historical tropical cyclone precipitation rate data and corresponding maximum wind speed data for a preset time period in the observation area are obtained through downloading or other reasonable methods. The historical tropical cyclone precipitation rate data is gridded, which can be precipitation data obtained through satellite inversion or gridded data interpolated from precipitation data obtained from weather stations. The grid size can be set to 25 km × 25 km or other reasonable values; there are no strict restrictions on this. Since the tropical cyclone precipitation rate data typically covers a wide range, to improve the accuracy of constructing a radial precipitation model for tropical cyclones, this embodiment uses the center of the tropical cyclone as the center and a radius of 1000 km or other reasonable values ​​for interception.

[0051] It should be noted that the maximum wind speed data corresponds to the data at the same time as the tropical cyclone precipitation rate data. There are many ways to obtain maximum wind speed data, which will not be elaborated on here. Furthermore, the preset time period can be set based on actual needs and circumstances; this embodiment does not impose excessive restrictions on it.

[0052] The acquired tropical cyclone precipitation rate data for the preset time period then needs to be processed to obtain historical radial precipitation rate curves corresponding to historical tropical cyclone precipitation rate data at multiple time points. The method of processing tropical cyclone precipitation rate data to obtain radial precipitation rate curves is a conventional method in this field and will not be elaborated on further here.

[0053] Step S102: Obtain the historical radial precipitation peak data, historical radial precipitation peak radius data, historical tropical cyclone precipitation center precipitation rate data, and historical radial precipitation attenuation radius data for each historical radial precipitation rate curve, respectively forming the historical radial precipitation peak data set, historical radial precipitation peak radius data set, historical tropical cyclone precipitation center precipitation rate data set, and historical radial precipitation attenuation radius data set.

[0054] Specifically, historical radial precipitation peak data, historical radial precipitation peak radius data, historical tropical cyclone precipitation center precipitation rate data, and historical radial precipitation attenuation radius data are obtained for each historical radial precipitation rate curve. The set of all historical radial precipitation peak data obtained based on the historical radial precipitation rate curve is called the historical radial precipitation peak data set. Similarly, the set of all historical radial precipitation peak radius data obtained based on the historical radial precipitation rate curve is called the historical radial precipitation peak radius data set. The set of all historical tropical cyclone precipitation center precipitation rate data obtained based on the historical radial precipitation rate curve is called the historical tropical cyclone precipitation center precipitation rate data set. The set of all historical radial precipitation attenuation radius data obtained based on the historical radial precipitation rate curve is called the historical radial precipitation attenuation radius data set.

[0055] In acquiring historical radial precipitation peak data, historical radial precipitation peak radius data, historical tropical cyclone precipitation center precipitation rate data, and historical radial precipitation attenuation radius data from the historical radial precipitation rate curve, the maximum precipitation rate of the radial precipitation rate curve is directly obtained as the historical radial precipitation peak data (in cases where multiple maximum precipitation rates exist, the maximum precipitation rate closer to the tropical cyclone center is selected as the historical radial precipitation peak data). The radius corresponding to the historical radial precipitation peak data is used as the historical radial precipitation peak radius data, and the precipitation rate at the tropical cyclone precipitation center location in the historical radial precipitation rate curve is used as the historical tropical cyclone precipitation center precipitation rate data. The historical radial precipitation attenuation radius data is obtained using the following method.

[0056] Obtaining historical radial precipitation attenuation radius data from historical radial precipitation rate curves includes: acquiring all concave points in the historical radial precipitation rate curves; selecting a preset radial precipitation rate threshold and filtering out all concave points whose radial precipitation rate is less than the preset threshold, using these filtered concave points as reserve concave points; then calculating the precipitation difference ratio on both sides of each reserve concave point, selecting a preset precipitation difference ratio threshold, and filtering out reserve concave points whose precipitation difference ratio is less than the preset threshold; the first reserve concave point whose precipitation difference ratio is less than the preset threshold, selected in order from the center of the tropical cyclone outwards, is taken as the radial precipitation attenuation point, and the distance from the radial precipitation attenuation point to the center of the corresponding tropical cyclone is the historical radial precipitation attenuation radius. This embodiment's radial precipitation attenuation radius determination method can effectively capture the location of the radial precipitation periphery, providing sufficient support for subsequent calculation of radial precipitation attenuation distance and further construction of the radial attenuation factor.

[0057] The preset radial precipitation rate threshold was discovered after observing a large number of samples and adjusting parameters. The selection criterion for the preset radial precipitation rate threshold is determined based on the peak precipitation rate on the radial precipitation curve. Specifically, the preset radial precipitation rate threshold is selected as follows: if the radial precipitation peak in the historical radial precipitation rate curve is greater than 10 mm / h, then the preset radial precipitation rate threshold is set to 1 mm / h; if the radial precipitation peak in the historical radial precipitation rate curve is in the range of 2.5-10 mm / h, then the preset radial precipitation rate threshold is set to 0.5 mm / h; if the radial precipitation peak in the historical radial precipitation rate curve is less than 2.5 mm / h, then the preset radial precipitation rate threshold is 0.3 mm / h.

[0058] The preset precipitation difference ratio threshold is also obtained by summarizing the patterns of a large number of historical samples. The preset precipitation difference ratio threshold is selected as follows: if the radial precipitation peak in the historical radial precipitation rate curve is greater than 2.5 mm / h, the preset precipitation difference ratio threshold is 5; if the radial precipitation peak in the historical radial precipitation rate curve is less than 2.5 mm / h, the preset precipitation difference ratio threshold is 3.

[0059] Furthermore, the ratio of precipitation difference between the left and right sides of the preparatory concave point is as follows: take the absolute value of the difference between the preparatory concave point and the maximum precipitation value on the left as A, and take the absolute value of the precipitation difference between the preparatory concave point and the adjacent convex point on the right as B. The ratio of A to B is the precipitation difference ratio between the left and right sides of the preparatory concave point.

[0060] Step S103: Fit the radial precipitation peak value expression based on the historical maximum wind speed data and the historical radial precipitation peak value data set; fit the radial precipitation peak radius expression based on the historical radial precipitation peak value data set and the historical radial precipitation peak radius data set; fit the tropical cyclone precipitation center precipitation rate expression based on the historical radial precipitation peak value data set and the historical tropical cyclone precipitation center precipitation rate data set; fit the radial precipitation attenuation radius expression based on the historical radial precipitation peak value data set and the historical radial precipitation attenuation radius data set.

[0061] Specifically, in this embodiment, the maximum wind speed of a tropical cyclone can be divided into equal intervals of 1 m / s. Regional statistics on the radial precipitation peak value within each wind speed interval are performed. A quantitative experiment is conducted based on historical maximum wind speed data and historical radial precipitation peak value data sets to express the relationship between the two. Finally, an exponential relationship is used to express the relationship between the maximum wind speed and the radial precipitation peak value. An optimization algorithm is used to search for the optimal fitting parameters. The fitted expression for the relationship between the maximum wind speed and the radial precipitation peak value (i.e., the radial precipitation peak value expression) is as follows:

[0062]

[0063] Where MRR is the radial precipitation peak, MWS is the maximum wind speed corresponding to the radial precipitation peak, and M1, M2, M3 and M4 are all parameters in the radial precipitation peak relationship expression.

[0064] Similarly, a quantitative experiment was conducted to assess the relationship between historical radial precipitation peak data sets and historical radial precipitation peak radius data sets. The relationship between radial precipitation peak and radial precipitation peak radius was also expressed using an exponential relationship. An optimization algorithm was used to search for the optimal fitting parameters. The fitted expression for the relationship between radial precipitation peak and radial precipitation peak radius (i.e., the radial precipitation peak radius expression) is as follows:

[0065]

[0066] Where RMR is the radial precipitation peak radius, MRR is the radial precipitation peak value corresponding to the radial precipitation peak radius, and N1, N2, N3 and N4 are all parameters in the radial precipitation peak radius relationship expression.

[0067] A quantitative experiment was conducted to investigate the relationship between historical radial precipitation peak data and historical tropical cyclone precipitation center rate data. The relationship was expressed as a linear function, and the least squares method was used to fit the linear function. The resulting expression for the relationship between historical radial precipitation peak data and historical tropical cyclone precipitation center rate (i.e., the expression for tropical cyclone precipitation center rate) is as follows:

[0068] RR0 = a1MRR + a2

[0069] Where RR0 is the precipitation rate at the center of a tropical cyclone, MRR is the radial precipitation peak corresponding to the precipitation rate at the center of a tropical cyclone, and a1 and a2 are parameters in the expression relating the precipitation rate at the center of a tropical cyclone.

[0070] A quantitative experiment was conducted to investigate the relationship between historical radial precipitation peak data and historical radial precipitation attenuation radius data. The relationship was also expressed linearly, and the fitted expression for the relationship between historical radial precipitation peak data and historical radial precipitation attenuation radius (i.e., the radial precipitation attenuation radius expression) is as follows:

[0071] RE=b1MRR+b2

[0072] Where RE is the radial precipitation attenuation radius, MRR is the radial precipitation peak corresponding to the radial precipitation attenuation radius, and b1 and b2 are parameters in the expression for the precipitation rate relationship of the tropical cyclone precipitation center.

[0073] Step S104: Construct the radial precipitation attenuation factor based on the radial precipitation peak expression, the radial precipitation peak radius expression, the tropical cyclone precipitation center precipitation rate expression, and the radial precipitation attenuation radius expression.

[0074] Specifically, the distance between the radial precipitation peak radius and the radial precipitation attenuation radius is the attenuation distance, while the difference in precipitation at the radial precipitation peak and the radial precipitation attenuation radius is the precipitation attenuation amount. Both the attenuation distance and the precipitation attenuation amount jointly determine the attenuation rate of radial precipitation per unit radius. Since the attenuation radius can be considered the outer periphery of tropical cyclone precipitation, the precipitation value at the attenuation radius is small and negligible. Therefore, the larger the radial precipitation peak and the smaller the attenuation distance, the greater the radial attenuation rate. Therefore, this application expresses the radial precipitation attenuation factor as a relationship between the precipitation rate at the tropical cyclone center, the radial precipitation peak, the radial precipitation peak radius, and the radial precipitation attenuation radius. The expression for the radial precipitation attenuation factor is as follows:

[0075]

[0076] Where RDF is the radial precipitation attenuation factor, A is a constant parameter, r is the distance from the center of the tropical cyclone, RMR is the radial precipitation peak radius, MRR is the radial precipitation peak value, and RE is the radial precipitation attenuation radius. Substituting the fitted expressions for radial precipitation peak value, radial precipitation peak radius, tropical cyclone precipitation center precipitation rate, and radial precipitation attenuation radius into the above equation yields the complete expression for the radial precipitation attenuation factor.

[0077] The constant parameter A is used to distinguish the different radial precipitation attenuation rates of different tropical cyclone intensities. For example, in the Northwest Pacific (my country), tropical cyclones can be divided into 6 intensity levels, denoted as CAT1 to CAT6, corresponding to tropical depression, tropical storm, severe tropical storm, typhoon, severe typhoon, and super typhoon, respectively. In this embodiment, the constant parameter A for the 6 intensity levels can be set to 25, 30, 35, 40, 47, and 52, respectively, and when the intensity is lower than CAT1, the constant parameter A can be set to 22.

[0078] Step S105: Based on the radial precipitation peak expression, the radial precipitation peak radius expression, the tropical cyclone precipitation center precipitation rate expression, and the radial precipitation attenuation factor, the radial precipitation radial precipitation model is formed by introducing them into the R-CLIPER model.

[0079] Specifically, the radial precipitation rate curve is characterized in two main parts: precipitation from the center of the tropical cyclone to the radial precipitation peak radius exhibits a linear variation, while precipitation outward from the radial precipitation peak radius shows an exponential decay. A precipitation decay factor is used to characterize the rate of exponential decay. This is achieved by incorporating the radial precipitation peak expression, the radial precipitation peak radius expression, the tropical cyclone precipitation center precipitation rate expression, and the radial precipitation decay factor into the R-CLIPER model to obtain a tropical cyclone radial precipitation model. The specific tropical cyclone radial precipitation model obtained is as follows:

[0080]

[0081] Among them, RR sym The simulated radial precipitation rate curve is given by RDF, where RDF is the radial precipitation attenuation factor, r is the distance from the tropical cyclone center, RMR is the radial precipitation peak radius, MRR is the radial precipitation peak value, and RE is the radial precipitation attenuation radius. The complete expression for the tropical cyclone radial precipitation model can be obtained by fitting the expressions for the radial precipitation peak value, radial precipitation peak radius, tropical cyclone precipitation center precipitation rate, and radial precipitation attenuation factor.

[0082] To illustrate the radial precipitation attenuation characterization effect of the tropical cyclone radial precipitation model constructed in this embodiment of the invention, this embodiment uses the tropical cyclone radial precipitation model constructed by the method disclosed in this embodiment of the invention and the existing R-CLIPER model. It extracts 3-hour precipitation rate data from the TRMM satellite with the tropical cyclone center as the center and a radius of 1000 kilometers; radial precipitation rate curves are set at 25-kilometer intervals; and precipitation simulations are performed for tropical cyclones of six intensity levels in the Northwest Pacific based on this data. Figure 2 This diagram shows the radial precipitation rate curves obtained by simulating precipitation of tropical cyclones at six intensity levels in the Northwest Pacific using a tropical cyclone radial precipitation model in Embodiment 1 of the present invention. Figure 3 This diagram illustrates the radial precipitation rate curves obtained by simulating precipitation from tropical cyclones of six intensity levels in the Northwest Pacific using the R-CLIPER model in Embodiment 1 of the present invention; the dashed line represents the actual radial precipitation rate curve, and the solid line represents the simulated radial precipitation rate curve. (Reference) Figure 2 and Figure 3 As can be seen, the tropical cyclone radial precipitation model constructed in this embodiment of the invention has significantly improved the characterization of radial precipitation attenuation after integrating the radial precipitation attenuation factor.

[0083] The method for constructing a radial precipitation model for tropical cyclones provided in this invention obtains a radial precipitation rate curve based on historical tropical cyclone precipitation rate data, and extracts multiple curve structure characteristic parameters from the radial precipitation rate curve. Then, based on the data of each curve structure characteristic parameter, an expression for each parameter is established / fitted. In the form of constructing a radial precipitation attenuation factor, the attenuation distance and precipitation attenuation are integrated into the construction process of the tropical cyclone radial precipitation model, so that the constructed tropical cyclone radial precipitation model has a significant improvement in characterizing the radial precipitation attenuation effect.

[0084] Example 2

[0085] To address the shortcomings of existing technologies, this invention provides a device for constructing a tropical cyclone radial precipitation model.

[0086] Figure 4 A schematic diagram of the structure of the tropical cyclone radial precipitation model construction device according to Embodiment 2 of the present invention is shown; Reference Figure 4 As shown, the tropical cyclone radial precipitation model construction device of this invention includes a historical data acquisition module, a historical parameter acquisition module, an expression fitting module, a radial precipitation attenuation factor construction module, and a model construction module.

[0087] The historical data acquisition module is used to acquire historical tropical cyclone precipitation rate data and historical maximum wind speed data within a preset time period in the observation area, and to construct historical radial precipitation rate curves for multiple time points based on the historical tropical cyclone precipitation rate data.

[0088] The historical parameter acquisition module is used to acquire the historical radial precipitation peak data, historical radial precipitation peak radius data, historical tropical cyclone precipitation center precipitation rate data, and historical radial precipitation attenuation radius data for each historical radial precipitation rate curve, respectively forming the historical radial precipitation peak data set, historical radial precipitation peak radius data set, historical tropical cyclone precipitation center precipitation rate data set, and historical radial precipitation attenuation radius data set.

[0089] The expression fitting module is used to fit the radial precipitation peak expression based on historical maximum wind speed data and historical radial precipitation peak data set, to fit the radial precipitation peak radius expression based on historical radial precipitation peak data set and historical radial precipitation peak radius data set, to fit the tropical cyclone precipitation center precipitation rate expression based on historical radial precipitation peak data set and historical tropical cyclone precipitation center precipitation rate data set, and to fit the radial precipitation attenuation radius expression based on historical radial precipitation peak data set and historical radial precipitation attenuation radius data set.

[0090] The radial precipitation attenuation factor construction module is used to construct the radial precipitation attenuation factor based on the radial precipitation peak expression, the radial precipitation peak radius expression, the tropical cyclone precipitation center precipitation rate expression, and the radial precipitation attenuation radius expression.

[0091] The model building module is used to introduce the radial precipitation peak expression, the radial precipitation peak radius expression, the tropical cyclone precipitation center precipitation rate expression, and the radial precipitation attenuation factor into the R-CLIPER model to form a tropical cyclone radial precipitation model.

[0092] The tropical cyclone radial precipitation model construction device provided in this invention obtains a radial precipitation rate curve based on historical tropical cyclone precipitation rate data, and obtains multiple curve structure feature parameters from the radial precipitation rate curve. Then, based on the data of each curve structure feature parameter, it establishes / fits the expression of each parameter, and integrates the attenuation distance and precipitation attenuation into the construction process of the tropical cyclone radial precipitation model in the form of constructing a radial precipitation attenuation factor. This significantly improves the ability of the constructed tropical cyclone radial precipitation model to characterize the radial precipitation attenuation effect.

[0093] Example 3

[0094] To address the aforementioned technical problems in the prior art, this embodiment of the invention also provides a storage medium storing a computer program that, when executed by a processor, can implement all the steps in the tropical cyclone radial precipitation model construction method of Embodiment 1.

[0095] The specific steps of the method for constructing the radial precipitation model of tropical cyclones and the beneficial effects obtained by applying the readable storage medium provided in the embodiments of the present invention are the same as those in Embodiment 1, and will not be repeated here.

[0096] It should be noted that storage media include various media that can store program code, such as ROM, RAM, magnetic disks, or optical disks.

[0097] Example 4

[0098] To address the aforementioned technical problems in the prior art, embodiments of the present invention also provide a terminal.

[0099] Figure 5 A schematic diagram of the terminal structure of Embodiment 4 of the present invention is shown, with reference to... Figure 5 In this embodiment, the terminal includes a processor and a memory that are interconnected. The memory is used to store computer programs, and the processor is used to execute the computer programs stored in the memory, so that when the terminal is executed, it can implement all the steps in the tropical cyclone radial precipitation model construction method described in Embodiment 1.

[0100] The specific steps of the method for constructing the radial precipitation model of tropical cyclones and the beneficial effects obtained by applying the terminal provided in this embodiment of the invention are the same as in Embodiment 1, and will not be repeated here.

[0101] It should be noted that the memory may include random access memory (RAM) and may also include non-volatile memory, such as at least one disk storage device. Similarly, the processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0102] While the embodiments disclosed in this invention are as described above, the content is merely for the purpose of facilitating understanding of the invention and is not intended to limit the invention. Any person skilled in the art to which this invention pertains may make any modifications and changes in form and detail of the implementation without departing from the spirit and scope disclosed herein; however, the scope of protection of this invention shall still be determined by the scope defined in the appended claims.

Claims

1. A method for constructing a radial precipitation model for tropical cyclones, comprising: Historical tropical cyclone precipitation rate data and historical maximum wind speed data within a preset time period are obtained in the observation area, and historical radial precipitation rate curves for multiple time points are constructed based on the historical tropical cyclone precipitation rate data; For each historical radial precipitation rate curve, acquire the historical radial precipitation peak data, historical radial precipitation peak radius data, historical tropical cyclone precipitation center precipitation rate data, and historical radial precipitation attenuation radius data to form the historical radial precipitation peak data set, historical radial precipitation peak radius data set, historical tropical cyclone precipitation center precipitation rate data set, and historical radial precipitation attenuation radius data set, respectively. Based on the historical maximum wind speed data and the historical radial precipitation peak data set, a radial precipitation peak value expression is fitted; based on the historical radial precipitation peak value data set and the historical radial precipitation peak radius data set, a radial precipitation peak radius expression is fitted; based on the historical radial precipitation peak value data set and the historical tropical cyclone precipitation center precipitation rate data set, a tropical cyclone precipitation center precipitation rate expression is fitted; and based on the historical radial precipitation peak value data set and the historical radial precipitation attenuation radius data set, a radial precipitation attenuation radius expression is fitted. A radial precipitation attenuation factor is constructed based on the radial precipitation peak value expression, the radial precipitation peak radius expression, the tropical cyclone precipitation center precipitation rate expression, and the radial precipitation attenuation radius expression; the radial precipitation attenuation factor expression is: ； Where RDF is the radial precipitation attenuation factor, A is a constant parameter, r is the distance from the center of the tropical cyclone, RMR is the radial precipitation peak radius, MRR is the radial precipitation peak, and RE is the radial precipitation attenuation radius. The radial precipitation peak value expression, the radial precipitation peak radius expression, the tropical cyclone precipitation center precipitation rate expression, and the radial precipitation attenuation factor are introduced into the R-CLIPER model to form a tropical cyclone radial precipitation model; the expression for the tropical cyclone radial precipitation model is as follows: ； where RR0 is the precipitation rate at the center of the tropical cyclone precipitation, where RR0 is the precipitation rate at the center of the tropical cyclone precipitation, RDF is the radial precipitation decay factor, r is the distance from the center of the tropical cyclone, RMR is the radial precipitation peak radius, MRR is the radial precipitation peak, and RE is the radial precipitation decay radius.

2. The method of claim 1, wherein, Obtain the historical radial precipitation attenuation radius data of the historical radial precipitation rate curve, including: Obtain all the concave points on the historical radial precipitation rate curve, and select the concave points whose radial precipitation rate is less than a preset radial precipitation rate threshold from all the concave points as pre-concave points; Obtain the precipitation difference ratio on both sides of all the prepared concave points, and select the first prepared concave point that meets the preset condition from all the prepared concave points in the order from the center of the tropical cyclone outward as the radial precipitation attenuation point. The distance of the radial precipitation attenuation point from the center of the corresponding tropical cyclone is the historical radial precipitation attenuation radius. The preset condition is that the precipitation difference ratio on both sides is less than the preset precipitation difference ratio threshold.

3. The method according to claim 2, characterized in that, If the radial precipitation peak value in the historical radial precipitation rate curve is greater than 10 mm / h, then the preset radial precipitation rate threshold is 1 mm / h; if the radial precipitation peak value in the historical radial precipitation rate curve is in the range of 2.5-10 mm / h, then the preset radial precipitation rate threshold is 0.5 mm / h; if the radial precipitation peak value in the historical radial precipitation rate curve is less than 2.5 mm / h, then the preset radial precipitation rate threshold is 0.3 mm / h. If the radial precipitation peak value in the historical radial precipitation rate curve is greater than 2.5 mm / h, the preset precipitation difference ratio threshold is 5; if the radial precipitation peak value in the historical radial precipitation rate curve is less than 2.5 mm / h, the preset precipitation difference ratio threshold is 3.

4. The method according to claim 1, characterized in that, Both the expression for the radial precipitation peak value and the expression for the radial precipitation peak radius are exponential relationships.

5. The method according to claim 1, characterized in that, Both the expression for the precipitation rate at the center of the tropical cyclone and the expression for the radial precipitation attenuation radius are linear relationships.

6. A device for constructing a radial precipitation model for a tropical cyclone, characterized in that, It includes a historical data acquisition module, a historical parameter acquisition module, an expression fitting module, a radial precipitation attenuation factor construction module, and a model construction module; The historical data acquisition module is used to acquire historical tropical cyclone precipitation rate data and historical maximum wind speed data within a preset time period in the observation area, and to construct historical radial precipitation rate curves for multiple time points based on the historical tropical cyclone precipitation rate data. The historical parameter acquisition module is used to acquire the historical radial precipitation peak data, historical radial precipitation peak radius data, historical tropical cyclone precipitation center precipitation rate data, and historical radial precipitation attenuation radius data for each of the historical radial precipitation rate curves, respectively forming a historical radial precipitation peak data set, a historical radial precipitation peak radius data set, a historical tropical cyclone precipitation center precipitation rate data set, and a historical radial precipitation attenuation radius data set; The expression fitting module is used to fit a radial precipitation peak expression based on the historical maximum wind speed data and the historical radial precipitation peak data set, to fit a radial precipitation peak radius expression based on the historical radial precipitation peak data set and the historical radial precipitation peak radius data set, to fit a tropical cyclone precipitation center precipitation rate expression based on the historical radial precipitation peak data set and the historical tropical cyclone precipitation center precipitation rate data set, and to fit a radial precipitation attenuation radius expression based on the historical radial precipitation peak data set and the historical radial precipitation attenuation radius data set. The radial precipitation attenuation factor construction module is used to construct a radial precipitation attenuation factor based on the radial precipitation peak value expression, the radial precipitation peak radius expression, the tropical cyclone precipitation center precipitation rate expression, and the radial precipitation attenuation radius expression; the radial precipitation attenuation factor expression is: ； Where RDF is the radial precipitation attenuation factor, A is a constant parameter, r is the distance from the center of the tropical cyclone, RMR is the radial precipitation peak radius, MRR is the radial precipitation peak, and RE is the radial precipitation attenuation radius. The model building module is used to incorporate the radial precipitation peak value expression, the radial precipitation peak radius expression, the tropical cyclone precipitation center precipitation rate expression, and the radial precipitation attenuation factor into the R-CLIPER model to form a tropical cyclone radial precipitation model; the expression for the tropical cyclone radial precipitation model is: ； Where RR0 is the precipitation rate at the center of a tropical cyclone. The simulated radial precipitation rate curve is defined by RDF, where RDF is the radial precipitation attenuation factor, r is the distance from the center of the tropical cyclone, RMR is the radial precipitation peak radius, MRR is the radial precipitation peak value, and RE is the radial precipitation attenuation radius.

7. A storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method for constructing a tropical cyclone radial precipitation model as described in any one of claims 1 to 5.

8. A terminal, characterized in that, include: A processor and a memory, wherein the memory and the processor are communicatively connected; The memory is used to store computer programs, and the processor is used to execute the computer programs stored in the memory so that the terminal performs the tropical cyclone radial precipitation model construction method as described in any one of claims 1 to 5.

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