Landing hollow typhoon identification method and device based on wind field and tropical cyclone path

Abstract

The invention relates to a landing hollow typhoon identification method and device based on a wind field and a tropical cyclone path, and the method comprises the steps: determining the typhoon center position corresponding to the hourly time of all typhoons in a landing typhoon sample set in the landing process, and calculating the inner-ring wind power, the outer-ring wind power and the maximum inner-ring wind measurement when the typhoons land; further distinguishing hollow structure characteristics of the typhoon according to landing typhoon sample set data and parameters such as inner ring wind power, outer ring wind power and inner ring maximum wind measurement, and finding out the typhoon with the hollow structure in the landing process; and finally, all typhoons with hollow structures in the landing typhoon sample set in the landing process are judged as hollow typhoons. According to the invention, the efficiency and accuracy of identifying the landing hollow typhoon in meteorological scientific research and business work can be improved. The construction and application of the method have positive practical significance for improving the typhoon refined wind and rain forecast capability and providing reference basis for typhoon defense work.

Description

Technical Field

[0001] The present invention relates to the technical field related to meteorological intelligent identification, and in particular to a method and device for identifying a landfalling hollow typhoon based on a wind field and a tropical cyclone path. Background Art

[0002] For some weaker typhoons, it is impossible to observe obvious eyewall structures during their development. It is often difficult and inaccurate to locate them using satellite cloud images or radar echo images. During their landing process, the main wind and rain impacts are distributed in the peripheral areas far from the center, while the wind and rain near the landing point are relatively weak or even without wind or rain. This type of typhoon is generally called a "hollow typhoon" in the business.

[0003] Hollow typhoons often cause difficulties in defense when they land. First, excessive defense near the landing point leads to waste of social resources, manpower and material resources. Second, insufficient defense in the peripheral areas easily leads to unexpected losses. Therefore, effective identification of hollow typhoons is of great practical significance for improving the ability of typhoon refined wind and rain forecasts and providing a reference basis for typhoon defense work.

[0004] At present, the identification of hollow typhoons mainly relies on the subjective experience of forecasters. There is no unified objective standard for defining hollow typhoons, and no research has proposed a clear method for identifying hollow typhoons.

[0005] Existing methods for typhoon identification include: (1) Identification and tracking methods for typhoon center and path: using meteorological elements such as vorticity to determine the location of the typhoon center, and then forming the typhoon path by connecting the center points. (2) Methods for identifying the typhoon eye and estimating the eye radius: using deep learning models and infrared cloud images to locate and identify images.

[0006] The existing typhoon center and path identification and tracking methods mainly locate the typhoon position, and do not identify the structural characteristics of the cyclone, which does not involve the structural characteristics of the typhoon itself. The typhoon eye identification and estimation method uses satellite cloud images, which is not applicable to all typhoons. Due to the limitations of observation data, this method can observe the well-developed typical typhoon eye area, but weak typhoons without obvious eye area structural characteristics are difficult to identify in cloud images and radar data. Summary of the invention

[0007] The purpose of the present invention is to solve at least one of the deficiencies of the prior art and to provide a method and device for identifying a landfalling hollow typhoon based on a wind field and a tropical cyclone path.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] Specifically, a landfall hollow typhoon identification method based on wind field and tropical cyclone path is proposed, including the following:

[0010] Obtain a sample set of landfalling typhoons;

[0011] Based on the landing typhoon sample set, the typhoon landing intensity and the maximum average wind force near the center when landing are obtained;

[0012] Based on the landfalling typhoon sample set, determining the hourly times of all typhoons landing in the sample set;

[0013] Based on the landfalling typhoon sample set, calculating the typhoon center position corresponding to the hourly times of all typhoons landing in the sample set;

[0014] Based on the landfalling typhoon sample set, combined with the hourly time and the typhoon center position, the inner circle wind force, the outer circle wind force and the inner circle maximum wind force of all typhoons at the time of landing are calculated;

[0015] Based on the typhoon landing intensity, the maximum average wind force near the center at landing, the inner circle wind force, the outer circle wind force and the maximum measured wind force in the inner circle at landing, the typhoon hollow structure conditions are judged for any typhoon in the landing typhoon sample set, and the typhoon with hollow structure during the landing process is found;

[0016] All typhoons with hollow structures during the landing process in the landfalling typhoon sample set are judged as hollow typhoons.

[0017] Further, specifically, a sample set of landfalling typhoons is obtained, including:

[0018] All typhoon cases that made landfall in the target area within a pre-selected time period were collected, and the landing information of all typhoons was counted, including the typhoon number, typhoon name, landing time, landing intensity, maximum average wind speed near the center at the time of landing, and the longitude and latitude of the typhoon center at the time of landing. The tropical cyclone best path dataset was downloaded, which included the longitude and latitude of the typhoon center. The above information was summarized to obtain a sample set of landing typhoons.

[0019] Further, specifically, based on the landfalling typhoon sample set, the hourly times of all typhoons landing in the sample set are determined, including:

[0020] For any typhoon in the landing typhoon sample set, when the landing time of the typhoon is before 30 minutes past a certain hour, this hour and the previous hour are selected as the hourly times of the typhoon landing process; if the landing time is 30 minutes past a certain hour and later, this hour and the next hour are selected as the hourly times of the typhoon landing process;

[0021] By using the above method, the landfalling typhoon sample set is traversed to obtain the hourly times of all typhoons landing therein.

[0022] Further, specifically, based on the landing typhoon sample set, the typhoon center positions corresponding to the hourly times of all typhoon landing processes are calculated, including:

[0023] For any typhoon in the landing typhoon sample set, the typhoon center position corresponding to the hourly time of the typhoon during landing is obtained by linear interpolation using the hourly time of the typhoon during landing and the longitude and latitude of the typhoon center in the tropical cyclone best path data set;

[0024] Repeat the above method to traverse the landfalling typhoon sample set to obtain the typhoon center position corresponding to the hourly time of all typhoon landing processes.

[0025] Further, specifically, the inner circle wind force, outer circle wind force and the maximum measured wind force of the inner circle of all typhoons at the time of landing are calculated, including:

[0026] Download the 2-minute average wind real-time observation data of all stations corresponding to the hourly time during the typhoon landing process. The stations include national ground meteorological observation stations and regional automatic stations, with a time resolution of 1 hour;

[0027] According to the typhoon center position at a certain hour, the area 80km away from the typhoon center is selected as the typhoon inner circle. The 2-minute average wind data of all stations within the typhoon inner circle at a certain hour are obtained. The top 5 largest wind speeds are taken and the average value is calculated as the inner circle wind force of the typhoon at this hour.

[0028] The calculation method of the outer ring wind force of a typhoon is the same as that of the inner ring wind force, but the outer ring range of the typhoon is selected from the area between 80km and 300km away from the typhoon center;

[0029] From the determination process of the hourly times, we know that the number of hourly times corresponding to each typhoon landing process is 2, so the inner circle wind force and outer circle wind force corresponding to the two hourly times are averaged respectively, and the average values ​​are used as the inner circle wind force and outer circle wind force of the typhoon landing;

[0030] During the typhoon landing process, the maximum 2-minute average wind observed in the inner circle corresponding to the hourly time is marked as the maximum measured wind in the inner circle when the typhoon landed.

[0031] Further, specifically, the typhoon hollow structure condition judgment is carried out, including:

[0032] When a typhoon satisfies the following three constraints at the same time, it is judged that the typhoon has a hollow structure during the landing process:

[0033] Condition 1: The wind level corresponding to the maximum wind measurement in the inner circle when the typhoon lands must be less than the typhoon landing intensity. When the typhoon landing intensity is less than or equal to level 8, the wind level corresponding to the maximum wind measurement in the inner circle when the typhoon lands must be 1 level or more less than the typhoon landing intensity. When the typhoon landing intensity is above level 8, the wind level corresponding to the maximum wind measurement in the inner circle when the typhoon lands must be 2 levels or more less than the typhoon landing intensity.

[0034] Condition 2: The inner circle wind force at the time of landing of the typhoon must have a certain difference from the maximum average wind force near the center at the time of landing. Specifically, the difference between the maximum average wind force near the center at the time of landing and the inner circle wind force of all typhoons in the landing typhoon sample set is calculated, and then the regression fitting value of the typhoon landing intensity and the wind speed difference is calculated. The fitting value is taken as the center-inner circle wind speed difference threshold of typhoons with different landing intensities. The wind speed difference corresponding to typhoons with different landing intensities must be greater than or equal to the center-inner circle wind speed difference threshold corresponding to the intensity;

[0035] Condition 3: The inner circle wind speed when the typhoon lands must be smaller than the outer circle wind speed.

[0036] Furthermore, the method further comprises:

[0037] After completing the determination of hollow typhoons in the landfalling typhoon sample set, the typhoons determined to be hollow typhoons are made into a hollow typhoon sample set, and the remaining typhoons are made into a non-hollow typhoon sample set for subsequent analysis.

[0038] The present invention also proposes a device for identifying a landfalling hollow typhoon based on a wind field and a tropical cyclone path, comprising the following:

[0039] Data acquisition module, used to obtain landfalling typhoon sample set;

[0040] An hourly time determination module, used to determine the hourly time of all typhoons during their landing process based on the landing typhoon sample set;

[0041] A typhoon center position calculation module is used to calculate the typhoon center position corresponding to the hourly time of all typhoon landing processes based on the landing typhoon sample set;

[0042] A key parameter calculation module is used to calculate the inner circle wind force, outer circle wind force and inner circle maximum wind force of all typhoons at the time of landing based on the landfall typhoon sample set, combined with the hourly time and the typhoon center position;

[0043] A key parameter extraction module, used to obtain the typhoon landing intensity and the maximum average wind force near the center when landing based on the landing typhoon sample set;

[0044] The hollow structure judgment module is used to judge the hollow structure conditions of any typhoon in the landing typhoon sample set based on the typhoon landing intensity, the maximum average wind force near the center at landing, the inner circle wind force, the outer circle wind force and the maximum measured wind force of the inner circle at landing, and find out the typhoon with a hollow structure during the landing process;

[0045] The hollow typhoon determination module is used to determine the typhoons with hollow structures during the landing process in the landing typhoon sample set as hollow typhoons.

[0046] The beneficial effects of the present invention are:

[0047] The present invention proposes a method and device for identifying a hollow typhoon at landfall based on a wind field and a tropical cyclone path. The method determines the typhoon center position corresponding to the hourly time of all typhoon landing processes in a landfall typhoon sample set, calculates the inner circle wind force, outer circle wind force and the maximum measured wind force of the inner circle when the typhoon lands, and further distinguishes the hollow structure characteristics of the typhoon based on the landfall typhoon sample set data and parameters such as the inner circle wind force, outer circle wind force and the maximum measured wind force of the inner circle, thereby improving the efficiency and accuracy of identifying hollow typhoons at landfall in meteorological scientific research and business work. The construction and application of this method has positive practical significance for improving the ability of typhoon refined wind and rain forecasting and providing a reference basis for typhoon defense work. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The above and other features of the present disclosure will become more apparent by describing in detail the embodiments shown in the accompanying drawings. The same reference numerals in the accompanying drawings of the present disclosure represent the same or similar elements. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure. For those skilled in the art, other accompanying drawings can be obtained based on these accompanying drawings without creative work. In the accompanying drawings:

[0049] Figure 1 Shown is a schematic diagram of a method for identifying a landfalling hollow typhoon based on a wind field and a tropical cyclone path according to the present invention;

[0050] Figure 2 It is a flow chart of calculating the inner circle wind force, outer circle wind force and the maximum wind measurement of the inner circle when a typhoon lands in the present invention;

[0051] Figure 3 Shown is a flow chart of the typhoon hollow structure condition judgment in the present invention;

[0052] Figure 4 The figure shows the inner and outer circle wind force schematic diagram of typhoons of different intensities landing in Guangdong from 2008 to 2022 in one embodiment of the present invention;

[0053] Figure 5The figure shows the wind field distribution diagram of the ground measuring station corresponding to the landing process of Typhoon “Nida” No. 1604 involved in the example verification of the present invention;

[0054] Figure 6 The figure shows the wind field distribution diagram of the ground measuring station corresponding to the landing process of Typhoon “Mulan” No. 2207 involved in the example verification of the present invention. DETAILED DESCRIPTION

[0055] The following will be combined with the embodiments and drawings to clearly and completely describe the concept, specific structure and technical effects of the present invention, so as to fully understand the purpose, scheme and effect of the present invention. It should be noted that the embodiments in this application and the features in the embodiments can be combined with each other without conflict. The same reference numerals used throughout the drawings indicate the same or similar parts.

[0056] Based on the above theoretical basis, Example 1, referring to Figure 1 The present invention proposes a method for identifying a landfalling hollow typhoon based on a wind field and a tropical cyclone path, comprising the following steps:

[0057] Obtain a sample set of landfalling typhoons;

[0058] Based on the landing typhoon sample set, the typhoon landing intensity and the maximum average wind force near the center when landing are obtained;

[0059] Based on the landfalling typhoon sample set, determining the hourly times of all typhoons landing in the sample set;

[0060] Based on the landfalling typhoon sample set, calculating the typhoon center position corresponding to the hourly times of all typhoons landing in the sample set;

[0061] Based on the landfalling typhoon sample set, combined with the hourly time and the typhoon center position, the inner circle wind force, the outer circle wind force and the inner circle maximum wind force of all typhoons at the time of landing are calculated;

[0062] Based on the typhoon landing intensity, the maximum average wind force near the center at landing, the inner circle wind force, the outer circle wind force and the maximum measured wind force of the inner circle at landing, the typhoon hollow structure conditions of any typhoon in the landing typhoon sample set are judged, and the typhoon with a hollow structure during the landing process is found;

[0063] Typhoons with hollow structures during the landing process in the landfalling typhoon sample set are judged as hollow typhoons.

[0064] In this embodiment 1, the typhoon center position corresponding to the hourly time of the typhoon landing process in the landing typhoon sample set is determined, and then the inner circle wind force, outer circle wind force and inner circle maximum wind force of all typhoons at the time of landing are further calculated. Finally, the hollow structure characteristics of the typhoon are distinguished based on the landing typhoon sample set data and parameters such as the inner circle wind force, outer circle wind force and inner circle maximum wind force.

[0065] As a preferred embodiment of the present invention, specifically, obtaining a landfall typhoon sample set includes:

[0066] All typhoon cases that made landfall in the target area within a pre-selected time period were collected, and the landing information of all typhoons was counted, including the typhoon number, typhoon name, landing time, landing intensity, maximum average wind speed near the center at the time of landing, and the longitude and latitude of the typhoon center at the time of landing. The tropical cyclone best path dataset was downloaded, which included the longitude and latitude of the typhoon center. The above information was summarized to obtain a sample set of landing typhoons.

[0067] As a preferred embodiment of the present invention, specifically, based on the landing typhoon sample set, the hourly times of all typhoon landing processes are determined, including:

[0068] For any typhoon in the landing typhoon sample set, when the landing time of the typhoon is before 30 minutes past a certain hour, this hour and the previous hour are selected as the hourly times of the typhoon landing process; if the landing time is 30 minutes past a certain hour and later, this hour and the next hour are selected as the hourly times of the typhoon landing process;

[0069] By using the above method, the landfalling typhoon sample set is traversed to obtain the hourly times of all typhoons landing therein.

[0070] As a preferred embodiment of the present invention, specifically, based on the landing typhoon sample set, the typhoon center position corresponding to the hourly time of all typhoon landing processes is calculated, including:

[0071] For any typhoon in the landing typhoon sample set, the typhoon center position corresponding to the hourly time of the typhoon during landing is obtained by linear interpolation using the hourly time of the typhoon during landing and the longitude and latitude of the typhoon center in the tropical cyclone best path data set;

[0072] The above method is repeated to traverse the landfalling typhoon sample set, and the typhoon center positions corresponding to the hourly times of all typhoon landing processes are obtained.

[0073] Reference Figure 2 As a preferred embodiment of the present invention, specifically, the inner circle wind force, outer circle wind force and the maximum measured wind force of the inner circle of all typhoons when they land are calculated, including:

[0074] Download the 2-minute average wind real-time observation data of all stations corresponding to the hourly time during the typhoon landing process. The stations include national ground meteorological observation stations and regional automatic stations, with a time resolution of 1 hour;

[0075] According to the typhoon center position at a certain hour, the area 80km away from the typhoon center is selected as the typhoon inner circle. The 2-minute average wind data of all stations within the typhoon inner circle at a certain hour are obtained. The top 5 largest wind speeds are taken and the average value is calculated as the inner circle wind force of the typhoon at this hour.

[0076] The calculation method of the outer ring wind force of a typhoon is the same as that of the inner ring wind force, but the outer ring range of the typhoon is selected from the area between 80km and 300km away from the typhoon center;

[0077] From the determination process of the hourly times, we know that the number of hourly times corresponding to each typhoon landing process is 2, so the inner circle wind force and outer circle wind force corresponding to the two hourly times are averaged respectively, and the average values ​​are used as the inner circle wind force and outer circle wind force of the typhoon landing;

[0078] During the typhoon landing process, the maximum 2-minute average wind observed in the inner circle corresponding to the hourly time is marked as the maximum measured wind in the inner circle when the typhoon landed.

[0079] Reference Figure 3 As a preferred embodiment of the present invention, specifically, the typhoon hollow structure condition judgment includes:

[0080] When a typhoon satisfies the following three constraints at the same time, it is judged that the typhoon has a hollow structure during the landing process:

[0081] Condition 1: The wind level corresponding to the maximum wind measurement in the inner circle when the typhoon lands must be less than the typhoon landing intensity. When the typhoon landing intensity is less than or equal to level 8, the wind level corresponding to the maximum wind measurement in the inner circle when the typhoon lands must be 1 level or more less than the typhoon landing intensity. When the typhoon landing intensity is above level 8, the wind level corresponding to the maximum wind measurement in the inner circle when the typhoon lands must be 2 levels or more less than the typhoon landing intensity.

[0082] Condition 2: The inner circle wind force at the time of landing of the typhoon must have a certain difference from the maximum average wind force near the center at the time of landing. Specifically, the difference between the maximum average wind force near the center at the time of landing and the inner circle wind force of all typhoons in the landing typhoon sample set is calculated, and then the regression fitting value of the typhoon landing intensity and the wind speed difference is calculated. The fitting value is taken as the center-inner circle wind speed difference threshold of typhoons with different landing intensities. The wind speed difference corresponding to typhoons with different landing intensities must be greater than or equal to the center-inner circle wind speed difference threshold corresponding to the intensity;

[0083] Condition 3: The inner circle wind speed when the typhoon lands must be smaller than the outer circle wind speed.

[0084] In this preferred embodiment, it should be noted that the number of landfalling typhoon samples selected within the specified time period in the specified area should be as small as possible, so as to obtain an effective threshold result when performing center-inner circle wind speed difference regression fitting. If the number of landfalling typhoon samples in a certain implementation process is small, the fitting value corresponding to the historical landfalling typhoon multi-sample set in the area can be used as the wind speed difference threshold for this judgment.

[0085] As a preferred embodiment of the present invention, the method further comprises:

[0086] After completing the determination of hollow typhoons in the landfalling typhoon sample set, the typhoons determined to be hollow typhoons are made into a hollow typhoon sample set, and the remaining typhoons are made into a non-hollow typhoon sample set for subsequent analysis.

[0087] Among them, in combination with various preferred embodiments of the present invention, specific applications are as follows:

[0088] The objective identification method of hollow-landing typhoons in the present invention is used to determine the hollow structures of all typhoons that landed in Guangdong from 2008 to 2022.

[0089] Step 1:

[0090] Using the "Tropical Cyclone Yearbook" of the Shanghai Typhoon Institute from 2008 to 2022, all typhoons that landed in Guangdong in the past 15 years and related landing information (including typhoon number, typhoon naming, landing time, landing intensity, maximum average wind force near the center at landing, and longitude and latitude position of the typhoon center at landing) were sorted out, and the data format is CSV format. Then, the CMA tropical cyclone best path data (including the longitude and latitude position of the typhoon center) from 2008 to 2022 was downloaded from the website of the Tropical Cyclone Data Center of the China Meteorological Administration. The data format is TXT format, the time resolution is 6 hours, and the above data is a sample data set of typhoons that landed in Guangdong from 2008 to 2022. There is no specific institutional source requirement for the tropical cyclone best path data set in the present invention. The selected time period is also not fixed, and the selected landing area can also be dynamically adjusted according to the study area.

[0091] Step 2:

[0092] Traverse the typhoon samples that landed in Guangdong from 2008 to 2022, select the hourly time of each typhoon sample during the landing process, and then use the hourly time and the longitude and latitude data of the typhoon center in the path data to obtain the longitude and latitude data of the typhoon center corresponding to the hourly time of all typhoon landing processes through linear interpolation. Each typhoon corresponds to 2 hourly times, with a time interval of 1h.

[0093] Step 3:

[0094] The meteorological big data platform "Tianqing" downloads the 2-minute average wind real-time observation data of the national ground meteorological observation stations and regional automatic stations corresponding to the hourly time of all typhoon landing processes, including Guangdong, Hainan and Fujian, with a time resolution of 1h and a data format of CSV. The corresponding area of ​​the average wind data downloaded in the present invention is not fixed and can be adjusted according to the landing area selected in step 1.

[0095] Step 5:

[0096] Traversing the samples of typhoons that landed in Guangdong from 2008 to 2022, for a certain hourly time during the landing process of a certain typhoon, the 2-minute average wind data of all stations within 80km away from the center of the typhoon at that time were selected, and the top 5 wind speed values ​​were taken to calculate the average after sorting the wind speed from large to small, and the average value was used as the inner circle wind force of the typhoon at that hourly time. In addition, the largest station wind speed value after sorting was taken as the maximum measured wind of the inner circle of the typhoon at that hourly time. The 2-minute average wind data of all stations within the range of 80km to 300km away from the center of the typhoon at that time were selected again, and the top 5 wind speed values ​​were taken to calculate the average after sorting the wind speed from large to small, and the average value was used as the outer circle wind force of the typhoon at that hourly time.

[0097] Step 6:

[0098] From the above steps, it can be seen that each typhoon corresponds to 2 hourly times, and each hourly time corresponds to an inner circle wind force, an outer circle wind force, and an inner circle maximum wind force. Take the average value of the inner circle wind force corresponding to the 2 hourly times as the inner circle wind force when the typhoon lands, take the average value of the outer circle wind force corresponding to the 2 hourly times as the outer circle wind force when the typhoon lands, and take the maximum value of the inner circle maximum wind force corresponding to the 2 hourly times as the inner circle maximum wind force when the typhoon lands. Traverse the samples of typhoons that landed in Guangdong from 2008 to 2022, obtain the inner circle wind force, outer circle wind force, and inner circle maximum wind force of each typhoon when it lands, and store the data in CSV format.

[0099] Step 7:

[0100] The difference between the maximum average wind speed near the center and the inner circle wind speed at the time of landing of the typhoon samples from 2008 to 2022 is calculated, and then the regression fitting value of the typhoon landing intensity and wind speed difference is calculated. The fitting value is taken as the center-inner circle wind speed difference threshold for typhoons with different landing intensities. The threshold is shown in Table 1.

[0101] Table 1 Center-inner circle wind speed difference thresholds corresponding to typhoons of different landfall intensities

[0102]

[0103] Step 8:

[0104] For each typhoon that makes landfall, when the typhoon's landing intensity is less than or equal to level 8, if the corresponding wind level of the maximum wind measured in the inner circle at the time of the typhoon's landing is less than the landing intensity by 1 level or more, the typhoon is considered to meet constraint condition 1. If the typhoon's landing intensity is greater than level 8, then when the corresponding wind level of the maximum wind measured in the inner circle at the time of the typhoon's landing is less than the landing intensity by 2 levels or more, the typhoon is considered to meet hollow constraint condition 1.

[0105] It can be seen from step 7 that each typhoon sample has a corresponding difference between the maximum average wind speed near the center and the inner circle wind speed at the time of landing. The wind speed difference and landing intensity of a typhoon are compared with the thresholds in Table 1. If the wind speed difference of the typhoon is greater than or equal to the threshold corresponding to its landing intensity, the typhoon is considered to meet the hollow constraint condition 2.

[0106] For each typhoon that makes landfall, when the inner circle wind force at the time of landing is less than the outer circle wind force, the typhoon is considered to meet the hollow constraint condition 3.

[0107] When a typhoon satisfies the above three conditions at the same time, the hollow typhoon identification method proposed in the present invention considers that the typhoon has a hollow structure during the landing process, and the typhoon is identified as a hollow typhoon.

[0108] Traverse the typhoon samples that landed in Guangdong from 2008 to 2022, and divide them into hollow typhoons and non-hollow typhoons through the above steps.

[0109] In order to verify the rationality of the method, the wind distribution of the inner and outer circles of all typhoons at landfall is plotted ( Figure 4 ). The red dots are all hollow typhoon samples identified by the method of the present invention, and the blue, yellow and light blue dots are non-hollow typhoon samples. It is believed in business forecasts that the main wind and rain impacts of hollow typhoons are distributed in the peripheral areas, and the wind and rain impacts near the center are relatively weak. Figure 4 It can be seen that all hollow typhoons (red dots) identified by the method of the present invention meet the characteristic that the outer circle wind force is greater than the inner circle wind force when making landfall, which is consistent with general cognition. Figure 4Middle red dot: hollow typhoon, blue dot, yellow dot and light blue dot: non-hollow typhoon, black dotted line is the situation where the wind force of inner and outer circles is equal. In addition, when some typhoons land, the wind force of the outer circle is greater than the wind force of the inner circle, but they are identified as non-hollow typhoons (yellow dot, light blue dot) by the method of the present invention. Among them, the yellow dot represents a non-hollow typhoon that meets constraint condition 3 but does not meet constraint condition 1, that is, the corresponding wind level of the maximum wind measurement of the inner circle when they land is not much different from the landing intensity, which is higher than the defined threshold of condition 1. This type of non-hollow typhoon includes Typhoon "Xiamba" No. 2203. Huazhou and Dianbai in Maoming City, where "Xiamba" landed, and the neighboring Zhanjiang City and Yangjiang City were all severely affected. It is an obvious non-hollow typhoon. The light blue dots represent non-hollow typhoons that meet constraints 1 and 3 but do not meet constraint 2. The difference between the maximum average wind force near the center and the inner circle wind force when these typhoons landed is less than the fitting threshold in condition 2. Such non-hollow typhoons include TD1601 and Typhoon Mangkhut No. 1822. Typhoon Mangkhut No. 1822 landed in Taishan, Jiangmen. It has the characteristics of strong intensity, large range of strong winds, severe wind and rain impact, and strong extreme strong winds. It has caused serious impacts on South China. The Typhoon Committee removed it from the list at the 51st Typhoon Committee Annual Meeting. This typhoon also does not meet the general perception of hollow typhoons. The above examples show that the setting of constraints 1 and 2 further ensures that the average wind force of the inner circle of the hollow typhoon is small and weaker than the typhoon's own landing intensity. The joint constraints of the three conditions can improve the accuracy of the identification results.

[0110] In order to further verify the reliability of the identification results of the present invention, the wind field distribution corresponding to the hollow typhoon identified by the method of the present invention is checked. Two actual identification cases are given here for reference.

[0111] Draw the time at 04:00 on August 2, 2016 ( Figure 5 ) and 11:00 on August 10, 2022 ( Figure 6 ) wind field distribution map. To make the wind field display clearer, wind measurements below level 5 have been filtered, and the red dot is the location of the typhoon center at this time. The red dotted circles are the inner and outer circles of the typhoon, which are 80km and 300km away from the typhoon center respectively. The wind force levels drawn are: light purple level 5, light green level 6, green level 7, blue level 8, orange level 9, and red level 10 or above.

[0112] Figure 5It shows that during the landing process of Typhoon No. 1604 "Nida", strong winds were mainly distributed in the outer circle, and the wind force in the inner circle was basically less than or equal to level 6-7, and it was judged as a hollow typhoon by the method of the present invention. However, it was difficult to identify its hollow structure based on the subjective business forecast at that time. Before "Nida" landed, Shenzhen, as its predicted landing point, carried out key deployment of typhoon defense. The Shenzhen Evening News "A Full Record of Typhoon "Nida" Attack on Shenzhen" reported that the entire city of Shenzhen implemented the "four stops" defense measures, but during its landing, Shenzhen did not experience strong winds and heavy rains. This shows that for hollow typhoons that are difficult to judge subjectively, the method of the present invention can effectively identify them and provide a reference for serving typhoon defense work. Typhoon No. 2207 "Mulan" has a very obvious hollow structure. Figure 6 , it is identified as a typical hollow typhoon in the subjective business forecast, and the method of the present invention determines it as a hollow typhoon, which is consistent with the subjective result.

[0113] From the above cases, it can be seen that the recognition results of the method described in the present invention are consistent with the general cognition of hollow typhoons in the corresponding wind field distribution. For the generally recognized hollow typhoons, this method can identify them, and for the hollow typhoons that are difficult to judge subjectively, this method can make effective supplementary judgments. Therefore, the hollow typhoon results obtained by the recognition method described in the present invention are accurate, reasonable and reliable.

[0114] The present invention also proposes a device for identifying a landfalling hollow typhoon based on a wind field and a tropical cyclone path, comprising the following:

[0115] Data acquisition module, used to obtain landfalling typhoon sample set;

[0116] An hourly time determination module, used to determine the hourly time of all typhoons during their landing process based on the landing typhoon sample set;

[0117] A typhoon center position calculation module is used to calculate the typhoon center position corresponding to the hourly time of all typhoon landing processes based on the landing typhoon sample set;

[0118] A key parameter calculation module is used to calculate the inner circle wind force, outer circle wind force and inner circle maximum wind force of all typhoons at the time of landing based on the landfall typhoon sample set, combined with the hourly time and the typhoon center position;

[0119] A key parameter extraction module, used to obtain the typhoon landing intensity and the maximum average wind force near the center when landing based on the landing typhoon sample set;

[0120] The hollow structure judgment module is used to judge the hollow structure conditions of any typhoon in the landing typhoon sample set based on the typhoon landing intensity, the maximum average wind force near the center at landing, the inner circle wind force, the outer circle wind force and the maximum measured wind force of the inner circle at landing, and find out the typhoon with a hollow structure during the landing process;

[0121] The hollow typhoon determination module is used to determine the typhoons with hollow structures during the landing process in the landing typhoon sample set as hollow typhoons.

[0122] In addition, each functional module in each embodiment of the present invention may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of software functional modules.

[0123] If the integrated module is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or system that can carry the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electrical carrier signal, telecommunication signal and software distribution medium, etc.

[0124] Although the description of the present invention has been quite detailed and specifically describes several described embodiments, it is not intended to be limited to any of these details or embodiments or any particular embodiment, but should be regarded as providing a broad possible interpretation of these claims in view of the prior art by reference to the appended claims, thereby effectively covering the intended scope of the present invention. In addition, the above description of the present invention is based on the embodiments foreseeable by the inventor, and its purpose is to provide a useful description, and those non-substantial changes to the present invention that have not yet been foreseen may still represent equivalent changes to the present invention.

[0125] The above is only a preferred embodiment of the present invention. The present invention is not limited to the above implementation. As long as the technical effect of the present invention is achieved by the same means, it should belong to the protection scope of the present invention. Within the protection scope of the present invention, its technical scheme and / or implementation method can have various modifications and changes.

Claims

1. A method for identifying landfalling hollow typhoons based on wind fields and tropical cyclone paths, characterized in that: Includes the following: Obtain a sample set of landfalling typhoons; Based on the landing typhoon sample set, the typhoon landing intensity and the maximum average wind force near the center when landing are obtained; Based on the landfalling typhoon sample set, determining the hourly times of all typhoons landing in the sample set; Based on the landfalling typhoon sample set, calculating the typhoon center position corresponding to the hourly times of all typhoons landing in the sample set; Based on the landfalling typhoon sample set, combined with the hourly time and the typhoon center position, the inner circle wind force, the outer circle wind force and the inner circle maximum wind force of all typhoons at the time of landing are calculated; Based on the typhoon landing intensity, the maximum average wind force near the center at landing, the inner circle wind force, the outer circle wind force and the maximum measured wind force in the inner circle at landing, the typhoon hollow structure conditions are judged for any typhoon in the landing typhoon sample set, and the typhoon with hollow structure during the landing process is found; All typhoons with hollow structures during the landing process in the landfalling typhoon sample set are judged as hollow typhoons.

2. The method for identifying a landfalling hollow typhoon based on wind field and tropical cyclone path according to claim 1, characterized in that: Specifically, a sample set of landfalling typhoons is obtained, including: All typhoon cases that made landfall in the target area within a pre-selected time period were collected, and the landing information of all typhoons was counted, including the typhoon number, typhoon name, landing time, landing intensity, maximum average wind speed near the center at the time of landing, and the longitude and latitude of the typhoon center at the time of landing. The tropical cyclone best path dataset was downloaded, which included the longitude and latitude of the typhoon center. The above information was summarized to obtain a sample set of landing typhoons.

3. The method for identifying a landfalling hollow typhoon based on wind field and tropical cyclone path according to claim 1, characterized in that: Specifically, based on the landfall typhoon sample set, the hourly times of all typhoons landing in the sample set are determined, including: For any typhoon in the landing typhoon sample set, when the landing time of the typhoon is before 30 minutes past a certain hour, this hour and the previous hour are selected as the hourly times of the typhoon landing process; if the landing time is 30 minutes past a certain hour and later, this hour and the next hour are selected as the hourly times of the typhoon landing process; By using the above method, the landfalling typhoon sample set is traversed to obtain the hourly times of all typhoons landing therein.

4. The method for identifying a landfalling hollow typhoon based on wind field and tropical cyclone path according to claim 2, characterized in that: Specifically, based on the landing typhoon sample set, the typhoon center positions corresponding to the hourly times of all typhoon landing processes are calculated, including: For any typhoon in the landing typhoon sample set, the typhoon center position corresponding to the hourly time of the typhoon during landing is obtained by linear interpolation using the hourly time of the typhoon during landing and the longitude and latitude of the typhoon center in the tropical cyclone best path data set; The above method is repeated to traverse the landfalling typhoon sample set, and the typhoon center positions corresponding to the hourly times of all typhoon landing processes are obtained.

5. The method for identifying a landfalling hollow typhoon based on wind field and tropical cyclone path according to claim 3, characterized in that: Specifically, the inner circle wind force, outer circle wind force and the maximum wind force of the inner circle of all typhoons at landfall are calculated, including: Download the 2-minute average wind real-time observation data of all stations corresponding to the hourly time during the typhoon landing process. The stations include national ground meteorological observation stations and regional automatic stations, with a time resolution of 1 hour; According to the typhoon center position at a certain hour, the area 80km away from the typhoon center is selected as the typhoon inner circle. The 2-minute average wind data of all stations within the typhoon inner circle at a certain hour are obtained. The top 5 largest wind speeds are taken and the average value is calculated as the inner circle wind force of the typhoon at this hour. The calculation method of the outer ring wind force of a typhoon is the same as that of the inner ring wind force, but the outer ring range of the typhoon is selected from the area between 80km and 300km away from the typhoon center; From the determination process of the hourly times, we know that the number of hourly times corresponding to each typhoon landing process is 2, so the inner circle wind force and outer circle wind force corresponding to the two hourly times are averaged respectively, and the average values ​​are used as the inner circle wind force and outer circle wind force of the typhoon landing; During the typhoon landing process, the maximum 2-minute average wind observed in the inner circle corresponding to the hourly time is marked as the maximum measured wind in the inner circle when the typhoon landed.

6. The method for identifying a landfalling hollow typhoon based on wind field and tropical cyclone path according to claim 5, characterized in that: Specifically, the typhoon hollow structure condition judgment includes: When a typhoon satisfies the following three constraints at the same time, it is judged that the typhoon has a hollow structure during the landing process: Condition 1: The wind level corresponding to the maximum wind measurement in the inner circle when the typhoon lands must be less than the typhoon landing intensity. When the typhoon landing intensity is less than or equal to level 8, the wind level corresponding to the maximum wind measurement in the inner circle when the typhoon lands must be 1 level or more less than the typhoon landing intensity. When the typhoon landing intensity is above level 8, the wind level corresponding to the maximum wind measurement in the inner circle when the typhoon lands must be 2 levels or more less than the typhoon landing intensity. Condition 2: The inner circle wind force at the time of landing of the typhoon must have a certain difference from the maximum average wind force near the center at the time of landing. Specifically, the difference between the maximum average wind force near the center at the time of landing and the inner circle wind force of all typhoons in the landing typhoon sample set is calculated, and then the regression fitting value of the typhoon landing intensity and the wind speed difference is calculated. The fitting value is taken as the center-inner circle wind speed difference threshold of typhoons with different landing intensities. The wind speed difference corresponding to typhoons with different landing intensities must be greater than or equal to the center-inner circle wind speed difference threshold corresponding to the intensity; Condition 3: The inner circle wind speed when the typhoon makes landfall must be smaller than the outer circle wind speed.

7. The method for identifying a landfalling hollow typhoon based on wind field and tropical cyclone path according to claim 1, characterized in that: The method further comprises, After completing the determination of hollow typhoons in the landfalling typhoon sample set, the typhoons determined to be hollow typhoons are made into a hollow typhoon sample set, and the remaining typhoons are made into a non-hollow typhoon sample set for subsequent analysis.

8. A device for identifying landfalling hollow typhoons based on wind fields and tropical cyclone paths, characterized in that: Includes the following: Data acquisition module, used to obtain landfalling typhoon sample set; An hourly time determination module is used to determine the hourly time of all typhoons during their landing process based on the landing typhoon sample set; A typhoon center position calculation module, used to calculate the typhoon center position corresponding to the hourly time of all typhoon landing processes based on the landing typhoon sample set; A key parameter calculation module is used to calculate the inner circle wind force, outer circle wind force and inner circle maximum wind force of all typhoons at the time of landing based on the landfall typhoon sample set, combined with the hourly time and the typhoon center position; A key parameter extraction module, used to obtain the typhoon landing intensity and the maximum average wind force near the center when landing based on the landing typhoon sample set; The hollow structure judgment module is used to judge the hollow structure conditions of any typhoon in the landing typhoon sample set based on the typhoon landing intensity, the maximum average wind force near the center at landing, the inner circle wind force, the outer circle wind force and the maximum measured wind force of the inner circle at landing, and find out the typhoon with a hollow structure during the landing process; The hollow typhoon determination module is used to determine the typhoons with hollow structures during the landing process in the landing typhoon sample set as hollow typhoons.

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