A method, system and device for detecting effective precipitation of a tropical cyclone and a storage medium

Abstract

This invention discloses a method, system, device, and storage medium for detecting effective precipitation in tropical cyclones, belonging to the field of tropical cyclone precipitation detection technology. The method includes: acquiring the center location, time information, and total daily precipitation of a tropical cyclone; dividing a buffer zone around the center location into a preset range, marking the grid within the buffer zone, and converting the buffer zone into a raster mask document; calculating the distance from the center point of the grid to the center location of each tropical cyclone, selecting the time information corresponding to the tropical cyclone with the smallest distance as the center time of that tropical cyclone passing through the grid; accumulating the total daily precipitation for a preset number of days before and after the center time to obtain the total precipitation caused by the tropical cyclone in the grid, and identifying grids with a total precipitation greater than a preset threshold as valid grids; calculating the cumulative area and cumulative precipitation of all valid grids as the total effective precipitation area and total effective precipitation of the tropical cyclone, thus completing the effective precipitation detection.

Description

Technical Field

[0001] This invention relates to a method, system, device, and storage medium for effective precipitation detection in tropical cyclones, belonging to the field of tropical cyclone precipitation detection technology. Background Technology

[0002] The heavy rainfall brought by cyclone rainbands often causes floods in the surrounding areas, greatly endangering people's lives and property. With the development of satellite observation technology, current satellite products can monitor the movement trajectory of tropical cyclones. At the same time, several global precipitation grid datasets have basically covered cyclone activity and precipitation areas. Against the backdrop of climate change, the intensity of tropical cyclones is likely to increase further, and the risk of tropical cyclones to people is also rising. Therefore, studying the effective precipitation of global tropical cyclones and the detection methods of precipitation areas is of positive significance for understanding the physical laws and future trends of tropical cyclone precipitation.

[0003] Traditional research methods mainly rely on ground-based observations of tropical cyclone precipitation in the areas through which they pass. While ground-based observations offer high precision, this traditional approach also has some drawbacks. First, the research scope is limited to land and constrained by instrument deployment, making it impossible to reconstruct the full picture of precipitation throughout the tropical cyclone's life cycle. Second, it does not clearly separate the precipitation area of ​​tropical cyclones from the precipitation influenced by surrounding non-tropical cyclones, making it difficult to standardize and quantify the precipitation processes of multiple tropical cyclones, which is not conducive to trend analysis. Summary of the Invention

[0004] The purpose of this invention is to provide an effective method, system, device, and storage medium for detecting precipitation in tropical cyclones, thereby solving the problems of limited ground instrument deployment and difficulty in standardizing and quantifying multiple tropical cyclone precipitation events in the prior art.

[0005] To achieve the above objectives, the present invention employs the following technical solution:

[0006] In a first aspect, the present invention provides a method for detecting effective precipitation in tropical cyclones, comprising:

[0007] Obtain the center location, time information, and total daily precipitation of tropical cyclones;

[0008] Divide the buffer area around the center position into a preset range, mark the grid within the buffer area, and convert the buffer area into a raster mask document;

[0009] Calculate the distance from the center point of the grid in the raster mask document to the center of each tropical cyclone, and select the time information corresponding to the tropical cyclone with the smallest distance as the time when the tropical cyclone passes through the center of the grid.

[0010] The total daily precipitation of the tropical cyclone in the grid is obtained by summing the daily total precipitation of the preset number of days before and after the center time. Grids with total precipitation greater than the preset threshold are considered as valid grids.

[0011] The cumulative area and cumulative precipitation of all effective grids are calculated as the total effective precipitation area and total effective precipitation of the tropical cyclone, thus completing the effective precipitation detection.

[0012] In conjunction with the first aspect, the center location of the tropical cyclone further includes the latitude and longitude of the tropical cyclone center.

[0013] In conjunction with the first aspect, further, a buffer area of ​​a preset range is defined around the center position, and the buffer area is converted into a raster mask document, including:

[0014] In Python packages or ArcMap software, based on the WGS1984 geographic coordinate system, the area around the center location within a preset range is divided into buffer areas, and the buffer areas are converted into raster mask documents.

[0015] In conjunction with the first aspect, the distance from the center point of the grid in the raster mask document to the center of the tropical cyclone is calculated using the following formula:

[0016]

[0017] in, R is the distance from the center point A of the grid in the raster mask document to the center point B of the tropical cyclone, where R is the Earth's radius, and A is the distance from the center point A of the grid in the raster mask document to the center point B of the tropical cyclone. j and A ω Let A represent the longitude and latitude of point B respectively. j and B ω These represent the longitude and latitude of point B, respectively.

[0018] In conjunction with the first aspect, the preset threshold for the total precipitation is 10 mm.

[0019] In conjunction with the first aspect, further, the cumulative area of ​​all effective grids is the sum of the areas of all effective grids, and the area of ​​the effective grids is calculated using the following formula:

[0020]

[0021] Where S is the area of ​​the effective grid, R is the Earth's radius, and λ1 and λ2 represent the longitudes of the left and right ends of the effective grid, respectively. and These represent the latitudes at the top and bottom of the effective grid, respectively.

[0022] In conjunction with the first aspect, the cumulative precipitation of all effective grids is further calculated by the following method: calculating the product of the total precipitation and the area of ​​each effective grid, and then summing the products of each effective grid to obtain the cumulative precipitation of all effective grids.

[0023] Secondly, the present invention also provides an effective precipitation detection system for tropical cyclones, comprising:

[0024] Data acquisition module: used to acquire the center location, time information, and total daily precipitation of tropical cyclones;

[0025] Buffer area division module: used to divide a buffer area around a preset range of the center position, mark the grid within the buffer area, and convert the buffer area into a raster mask document;

[0026] Center Time Calculation Module: Used to calculate the distance from the center point of the grid in the raster mask document to the center position of each tropical cyclone, and select the time information corresponding to the tropical cyclone with the smallest distance as the center time of the tropical cyclone passing through the grid;

[0027] Effective grid selection module: It is used to accumulate the total daily precipitation of the tropical cyclone in the grid by adding up the total precipitation of the preset number of days before and after the center time, and select the grid with the total precipitation greater than the preset threshold as the effective grid.

[0028] Effective precipitation calculation module: used to calculate the cumulative area and cumulative precipitation of all effective grids as the total effective precipitation area and total effective precipitation of the tropical cyclone, and to complete the effective precipitation detection.

[0029] Thirdly, the present invention also provides an effective precipitation detection device for tropical cyclones, including a processor and a storage medium;

[0030] The storage medium is used to store instructions;

[0031] The processor is configured to operate according to the instructions to perform the steps of the method according to any one of the first aspects.

[0032] Fourthly, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in any of the first aspects.

[0033] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0034] This invention provides a method, system, device, and storage medium for detecting effective precipitation in tropical cyclones. By dividing the buffer zone, it further detects effective precipitation based on the buffer zone, clearly separating tropical cyclone precipitation from precipitation caused by surrounding non-tropical cyclones. It can calculate the total effective precipitation and total effective precipitation area (precipitation influence range) over the entire development cycle of a tropical cyclone, including land and ocean surfaces. This is beneficial for comprehensively, accurately, and uniformly quantifying the precipitation process of multiple tropical cyclones, while avoiding many limitations of ground-based rain measuring instruments. Attached Figure Description

[0035] Figure 1 This is one of the flowcharts of an effective precipitation detection method for tropical cyclones provided in an embodiment of the present invention;

[0036] Figure 2 This is the second flowchart of a method for detecting effective precipitation in tropical cyclones provided in an embodiment of the present invention;

[0037] Figure 3 This is a schematic diagram of the path and affected area of ​​a tropical cyclone provided in an embodiment of the present invention. Detailed Implementation

[0038] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to illustrate the technical solution of the present invention more clearly, and should not be used to limit the scope of protection of the present invention.

[0039] Example 1

[0040] This example uses IBTRAS (International Best Track Archive for Climate Stewardship) global best track archive and ERA5-Total Precipitation reanalysis global grid precipitation data to analyze a large cyclone, Katya (ID: IBTRAS-SID-2011240N10341), in 2011.

[0041] like Figure 1 As shown in the figure, an embodiment of the present invention provides a method for detecting effective precipitation in tropical cyclones, comprising the following steps:

[0042] S1. Obtain the center location, time information, and total daily precipitation of the tropical cyclone.

[0043] Extract the corresponding IBTRACS-lat, IBTRACS-lon, and IBTRACS-time records for this tropical cyclone from the archive. The records are updated every 3 hours and contain the latitude and longitude of the tropical cyclone center, as well as the corresponding time information. Download the necessary ERA5-Total Precipitation data (including daily total precipitation) based on the time information range, with an accuracy of 0.5°×0.5° / day.

[0044] S2. Divide the buffer area around the center position into a preset range, mark the grid within the buffer area, and convert the buffer area into a raster mask document.

[0045] Commercial software or Python packages can be used to perform buffer zone analysis and calculations in geospatial coordinate systems.

[0046] In this embodiment, ArcMap software is used to perform calculations in the WGS1984 geographic coordinate system. The latitude and longitude points formed by the IBTACS-lat and IBTACS-lon records extracted in step S1 are connected by the shortest path to obtain a path line. A 500km buffer zone is then calculated around the path line to obtain the buffer area. The result of the buffer area (affected area) division is as follows: Figure 3 As shown, the grid within the buffer area is marked in a raster mask document with the same precision as the precipitation data in step S1, and finally the divided buffer area is converted into a raster mask document.

[0047] S3. Calculate the distance from the center point of the grid in the raster mask document to the center of each tropical cyclone, and select the time information corresponding to the tropical cyclone with the smallest distance as the center time of the tropical cyclone passing through the grid.

[0048] For each grid marked in step S2, calculate the distance from the center point of the grid to the center of each tropical cyclone using the following formula:

[0049]

[0050] in, R is the distance from the center point A of the grid in the raster mask document to the center point B of the tropical cyclone, where R is the Earth's radius, and A is the distance from the center point A of the grid in the raster mask document to the center point B of the tropical cyclone. j and A ω Let A represent the longitude and latitude of point B respectively. j and B ω These represent the longitude and latitude of point B, respectively.

[0051] Search for the center location of the tropical cyclone closest to the grid center point, and use the time information corresponding to that tropical cyclone as the center time of the tropical cyclone passing through the grid.

[0052] S4. The total daily precipitation of the tropical cyclone in the grid is obtained by summing the daily total precipitation of the preset number of days before and after the center time. Grids with total precipitation greater than the preset threshold are considered as valid grids.

[0053] For each grid with a center time calculated in step S3 (in this embodiment, the center time is a specific date), the total daily precipitation for the center date and the two days before and after the center date (a total of 5 days) is extracted and summed. The summed result is the total precipitation caused by the tropical cyclone in the grid.

[0054] Grids with a total precipitation greater than 10 mm are considered valid grids.

[0055] S5. Calculate the cumulative area and cumulative precipitation of all effective grids as the total effective precipitation area and total effective precipitation of the tropical cyclone, and complete the effective precipitation detection.

[0056] The area of ​​each effective grid cell is calculated based on the latitude and longitude of the grid, using the following formula:

[0057]

[0058] Where S is the area of ​​the effective grid, R is the Earth's radius, and λ1 and λ2 represent the longitudes of the left and right ends of the effective grid, respectively. and These represent the latitudes at the top and bottom of the effective grid, respectively.

[0059] The cumulative area of ​​all valid grids is the sum of the areas of all valid grids.

[0060] The cumulative precipitation for all effective grids is calculated as follows: the total precipitation for each effective grid is multiplied by its area, and then the products for each effective grid are summed to obtain the cumulative precipitation for all effective grids.

[0061] Example 2

[0062] This example uses IBTRAS (International Best Track Archive for Climate Stewardship) global best track archive and ERA5-Total Precipitation reanalysis global grid precipitation data to analyze a large cyclone, Katya (ID: IBTRAS-SID-2011240N10341), in 2011.

[0063] like Figure 2 As shown in the figure, an embodiment of the present invention provides a method for detecting effective precipitation in tropical cyclones, comprising the following steps:

[0064] S1. Obtain the required tropical cyclone track data and gridded precipitation data.

[0065] The path data includes the location and time information of the tropical cyclone center, and the grid precipitation data includes the total daily precipitation.

[0066] Extract the corresponding IBTRACS-lat, IBTRACS-lon, and IBTRACS-time records for this cyclone from the archive. The records are updated every 3 hours and contain the cyclone center latitude, cyclone center longitude, and the corresponding time information. Download the required ERA5-Total Precipitation precipitation data based on the time information range, with an accuracy of 0.5°×0.5° / day.

[0067] S2. Calculate the area within 500km around the tropical cyclone path data, mark the grid within the area, and generate grid mask data.

[0068] The area surrounding the center location obtained in step S1 is divided into a 500km buffer zone. The result of the buffer zone (affected area) division is as follows: Figure 3 As shown, the grid within the buffer area is marked in a raster mask document with the same precision as the precipitation data in step S1, and finally the divided buffer area is converted into a raster mask document.

[0069] S3. For each grid marked in step S2, calculate the nearest path information point (the point corresponding to the center position) to each grid within the range, and obtain the center time of each grid.

[0070] For each grid marked in step S2, calculate the distance from the center point of the grid to the center of each tropical cyclone using the following formula:

[0071]

[0072] in, R is the distance from the center point A of the grid in the raster mask document to the center point B of the tropical cyclone, where R is the Earth's radius, and A is the distance from the center point A of the grid in the raster mask document to the center point B of the tropical cyclone. j and A ω Let A represent the longitude and latitude of point B respectively. j and B ω These represent the longitude and latitude of point B, respectively.

[0073] Search for the center location of the tropical cyclone closest to the grid center point, and use the time information corresponding to that tropical cyclone as the center time of the tropical cyclone passing through the grid.

[0074] S4. For each grid, based on the grid's center time, extract precipitation data (total daily precipitation) for 2 days before and after that time (a total of 5 days, including the date of that time). The cumulative value is the total precipitation caused by the tropical cyclone in that grid.

[0075] S5. Search all grids with a total precipitation greater than 10 mm (effective grids), and record their total area as the total effective precipitation area of ​​the tropical cyclone in this event.

[0076] The area of ​​each effective grid cell is calculated based on the latitude and longitude of the grid, using the following formula:

[0077]

[0078] Where S is the area of ​​the effective grid, R is the Earth's radius, and λ1 and λ2 represent the longitudes of the left and right ends of the effective grid, respectively. and These represent the latitudes at the top and bottom of the effective grid, respectively.

[0079] The cumulative area of ​​all valid grids is the sum of the areas of all valid grids.

[0080] S6. Search all grids with a total precipitation greater than 10 mm (effective grids), and record their total precipitation as the total effective precipitation of this tropical cyclone.

[0081] The cumulative precipitation for all effective grids is calculated as follows: the total precipitation for each effective grid is multiplied by its area, and then the products for each effective grid are summed to obtain the cumulative precipitation for all effective grids.

[0082] In this embodiment, the total effective precipitation area was calculated to be 1.1142 × 10⁻⁶. 7 km 2 The total effective precipitation was 5.2200 × 10⁻⁶. 11 m 3 .

[0083] Example 3

[0084] An embodiment of the present invention provides an effective precipitation detection system for tropical cyclones, comprising:

[0085] Data acquisition module: used to acquire the center location, time information, and total daily precipitation of tropical cyclones;

[0086] Buffer area division module: used to divide a buffer area around a preset range of the center position, mark the grid within the buffer area, and convert the buffer area into a raster mask document;

[0087] Center Time Calculation Module: Used to calculate the distance from the center point of the grid in the raster mask document to the center position of each tropical cyclone, and select the time information corresponding to the tropical cyclone with the smallest distance as the center time of the tropical cyclone passing through the grid;

[0088] Effective grid selection module: It is used to accumulate the total daily precipitation of the tropical cyclone in the grid by adding up the total precipitation of the preset number of days before and after the center time, and select the grid with the total precipitation greater than the preset threshold as the effective grid.

[0089] Effective precipitation calculation module: used to calculate the cumulative area and cumulative precipitation of all effective grids as the total effective precipitation area and total effective precipitation of the tropical cyclone, and to complete the effective precipitation detection.

[0090] Example 4

[0091] An embodiment of the present invention provides an effective precipitation detection device for tropical cyclones, comprising a processor and a storage medium;

[0092] The storage medium is used to store instructions;

[0093] The processor is configured to operate according to the instructions to perform steps according to the following method:

[0094] Obtain the center location, time information, and total daily precipitation of tropical cyclones;

[0095] Divide the buffer area around the center position into a preset range, mark the grid within the buffer area, and convert the buffer area into a raster mask document;

[0096] Calculate the distance from the center point of the grid in the raster mask document to the center of each tropical cyclone, and select the time information corresponding to the tropical cyclone with the smallest distance as the time when the tropical cyclone passes through the center of the grid.

[0097] The total daily precipitation of the tropical cyclone in the grid is obtained by summing the daily total precipitation of the preset number of days before and after the center time. Grids with total precipitation greater than the preset threshold are considered as valid grids.

[0098] The cumulative area and cumulative precipitation of all effective grids are calculated as the total effective precipitation area and total effective precipitation of the tropical cyclone, thus completing the effective precipitation detection.

[0099] Example 5

[0100] The computer-readable storage medium provided in this embodiment of the invention stores a computer program thereon, which, when executed by a processor, implements the steps of the following method:

[0101] Obtain the center location, time information, and total daily precipitation of tropical cyclones;

[0102] Divide the buffer area around the center position into a preset range, mark the grid within the buffer area, and convert the buffer area into a raster mask document;

[0103] Calculate the distance from the center point of the grid in the raster mask document to the center of each tropical cyclone, and select the time information corresponding to the tropical cyclone with the smallest distance as the time when the tropical cyclone passes through the center of the grid.

[0104] The total daily precipitation of the tropical cyclone in the grid is obtained by summing the daily total precipitation of the preset number of days before and after the center time. Grids with total precipitation greater than the preset threshold are considered as valid grids.

[0105] The cumulative area and cumulative precipitation of all effective grids are calculated as the total effective precipitation area and total effective precipitation of the tropical cyclone, thus completing the effective precipitation detection.

[0106] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0107] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0108] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0109] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0110] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for detecting effective precipitation from a tropical cyclone, the method comprising: The method comprises the following steps: obtaining the center position, time information and daily total precipitation of a tropical cyclone; dividing a buffer area with a preset range around the center position, marking the grids in the buffer area, and converting the buffer area into a grid mask document; calculating the distance from the center point of the grid in the grid mask document to the center position of each tropical cyclone, and selecting the time information corresponding to the tropical cyclone with the minimum distance as the center time of the tropical cyclone passing through the grid; accumulating the daily total precipitation in the preset number of days before and after the center time to obtain the total precipitation caused by the tropical cyclone in the grid, and taking the grid with a total precipitation greater than a preset threshold as an effective grid; calculating the cumulative area and cumulative precipitation of all effective grids as the total effective precipitation area and total effective precipitation of the tropical cyclone, and completing the effective precipitation detection; dividing a buffer area with a preset range around the center position, and converting the buffer area into a grid mask document, which comprises: in a python package or ArcMap software, based on the WGS1984 geographic coordinate system, dividing the area with a preset range around the center position into a buffer area, and converting the buffer area into a grid mask document.

2. The method of claim 1, wherein, The center position of the tropical cyclone comprises the latitude and longitude of the center of the tropical cyclone.

3. The method of claim 1, wherein, The distance from the center point of the grid in the grid mask document to the center position of the tropical cyclone is calculated by the following formula: ； wherein, is the center point of the grid in the grid mask document A to the center position of the tropical cyclone B , is the radius of the earth, and denote A the longitude and latitude of the point, and denote B the longitude and latitude of the point.

4. The method of claim 1, wherein, The preset threshold of the total precipitation is 10 mm.

5. The method of claim 1, wherein, The cumulative area of all effective grids is the sum of the areas of all effective grids, and the area of an effective grid is calculated by the following formula: ； wherein, is the area of the effective grid, is the radius of the earth, and denote the longitude of the left and right ends of the effective grid, respectively, and denote the latitude of the upper and lower ends of the effective grid, respectively.

6. The method of claim 5, wherein, The cumulative precipitation of all effective grids is calculated by the following method: calculating the product of the total precipitation and the area of each effective grid, and then accumulating the product of each effective grid to obtain the cumulative precipitation of all effective grids.

7. A tropical cyclone effective precipitation detection system characterized by, The method comprises the following steps: a data acquisition module for obtaining the center position, time information and daily total precipitation of a tropical cyclone; a buffer area division module for dividing a buffer area with a preset range around the center position, marking the grids in the buffer area, and converting the buffer area into a grid mask document; a center time calculation module for calculating the distance from the center point of the grid in the grid mask document to the center position of each tropical cyclone, and selecting the time information corresponding to the tropical cyclone with the minimum distance as the center time of the tropical cyclone passing through the grid; an effective grid selection module for accumulating the daily total precipitation in the preset number of days before and after the center time to obtain the total precipitation caused by the tropical cyclone in the grid, and taking the grid with a total precipitation greater than a preset threshold as an effective grid; an effective precipitation calculation module for calculating the cumulative area and cumulative precipitation of all effective grids as the total effective precipitation area and total effective precipitation of the tropical cyclone, and completing the effective precipitation detection; dividing a buffer area with a preset range around the center position, and converting the buffer area into a grid mask document, which comprises: in a python package or ArcMap software, based on the WGS1984 geographic coordinate system, dividing the area with a preset range around the center position into a buffer area, and converting the buffer area into a grid mask document.

8. A tropical cyclone effective precipitation detection apparatus characterized by, The method comprises a processor and a storage medium. The storage medium is used to store instructions. The processor is configured to operate on the instructions to perform the steps of the method according to any one of claims 1 to 6.

9. A computer readable storage medium having stored thereon a computer program, characterized in that The program, which when executed by the processor, implements the steps of the method according to any one of claims 1 to 6.

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