Space-borne and multi-band ground-based radar reflectivity factor joint verification method and system

Abstract

The invention relates to the technical field of meteorological analysis, and more specifically relates to a satellite-borne and multiband ground-based radar reflectivity factor joint verification method and a satellite-borne and multiband ground-based radar reflectivity factor joint verification system. The scheme comprises the following steps: setting data sources of a spaceborne radar and a ground-based weather radar; performing data quality control according to the data sources of the spaceborne radar and the ground-based weather radar to form a corrected data source; matching and comparing the reflectivity factors of the spaceborne radar and the ground-based weather radar according to the corrected data source to form optimal pairing data; establishing a fused networking radar consistency evaluation algorithm to determine an alarm list, and forming a problem level; standard comparison is carried out on the ground-based radar reflectivity factors to form a matching result of the standard database and the novel spaceborne radar FY3-G / PMR; evaluation classification is set, and evaluation results under different classifications of the matching result of the standard database and the novel spaceborne radar FY3-G / PMR are formed and stored.

Description

Technical Field

[0001] The present invention relates to the field of meteorological analysis technology, and more specifically, to a method and system for jointly verifying reflectivity factors of satellite-borne and multi-band ground-based radars. Background Art

[0002] On April 16, 2023, China's first precipitation measurement-dedicated meteorological satellite Fengyun-3G (FY-3G) was successfully launched at the Jiuquan Satellite Launch Center. The precipitation measurement radar (PMR) is the main payload on the precipitation measurement satellite, including two radars in the Ku and Ka bands, which can obtain three-dimensional structural information inside the precipitation system. The secondary products of FY3-G / PMR include bright band detection, precipitation classification, three-dimensional drop spectrum profile, three-dimensional precipitation rate profile, and three-dimensional equivalent radar reflectivity factor profile. There is an urgent need to conduct authenticity verification of FY3-G / PMR secondary products, evaluate and verify the accuracy and applicability of secondary product data, and provide a reference for the improvement and optimization of FY3-G / PMR secondary product algorithms. Among them, the radar reflectivity factor is an important parameter of FY3-G / PMR secondary products.

[0003] Prior to the technology of the present invention, the previous methods for testing the reflectivity factor of the precipitation radar (Dual-Frequency Precipitation Radar, DPR) carried by the Global Precipitation Measurement Mission (Global Precipitation Measurement Mission, GPM) and the precipitation radar (Precipitation Radar, PR) on the Tropical Rainfall Measuring Mission (Tropical Rainfall Measuring Mission, TRMM) were mostly to directly use the S-band ground-based weather radar to carry out satellite-ground radar consistency analysis research, but in fact, China's ground-based weather radars mainly include S-band, C-band, and X-band. The three-band ground-based radars are coordinated for observation, each with its own advantages. The S-band ground-based radar has the smallest attenuation, the widest detection range, the highest data quality, but the lowest resolution, the X-band ground-based radar has the strongest attenuation, the smallest detection range, slightly worse data quality, but the highest resolution, and can observe detailed information on precipitation in a small area more carefully than the S-band ground-based radar, while the C-band ground-based radar attenuation, detection range and resolution are between the S-band and X-band ground-based radars. At present, the ground-based weather radars in central and coastal areas of China are mainly S-band, the northeast, northwest and southwest regions are mainly C-band, and X-band ground-based radars are scattered in various provinces. In order to carry out the authenticity verification and evaluation of the precipitation star reflectivity factor in China, ground-based radars of all three bands must be used to cover the whole of China, and each has its own advantages. In addition, these ground-based radars are widely distributed, with different technical support and maintenance conditions. Due to limited calibration methods, there will be inconsistent observation results in the overlapping areas of radars at each station. The quality of ground-based weather radar data at each station is uneven, which causes errors in the authenticity verification of the precipitation star reflectivity factor. Therefore, it is urgent to carry out a joint calibration of the reflectivity factors of space-borne and multi-band ground-based radars. Summary of the invention

[0004] In view of the above problems, the present invention proposes a method and system for jointly verifying the reflectivity factors of satellite-borne and multi-band ground-based radars, matches and compares the reflectivity factors of multi-band ground-based weather radars (S, C, and X bands) and satellite-borne radar GPM / DPR, establishes algorithms for matching ground-to-ground radar reflectivity factors and satellite-to-ground radar reflectivity factors, thereby establishing a fused networked radar consistency evaluation algorithm, verifies the reflectivity factor data of ground-based weather radars, and generates a standard database and a problem list for ground-based weather radars; based on the standard database of ground-based weather radars, the authenticity verification of the reflectivity factors of the new satellite-borne radar FY3-G / PMR is carried out using the satellite-to-ground radar reflectivity factor matching algorithm, forming a set of joint verification methods and systems for reflectivity factors of satellite-borne and multi-band ground-based radars.

[0005] According to a first aspect of an embodiment of the present invention, a method for jointly verifying reflectivity factors of spaceborne and multi-band ground-based radars is provided.

[0006] In one or more embodiments, preferably, the method for jointly verifying the reflectivity factors of spaceborne and multi-band ground-based radars includes:

[0007] Set up data sources for spaceborne radar and ground-based weather radar;

[0008] Performing data quality control based on the data sources of the spaceborne radar and the ground-based weather radar to form a corrected data source;

[0009] Match and compare the reflectivity factors of the spaceborne radar GPM / DPR and the ground-based weather radar based on the corrected data source to form the optimal pairing data;

[0010] Establish a fusion network radar consistency assessment algorithm to determine the alarm list and form a problem level;

[0011] Conduct standard comparison of ground-based radar reflectivity factors to form matching results between the standard database and the new space-borne radar FY3-G / PMR;

[0012] Set the evaluation categories, form the matching results of the standard database and the new spaceborne radar FY3-G / PMR under different categories and store them.

[0013] In one or more embodiments, preferably, the setting of the data sources of the spaceborne radar and the ground-based weather radar specifically includes:

[0014] The satellite-borne radar GPM / DPR data source is set to use the Global Precipitation Satellite (GPM) Dual-frequency Rainfall Radar (DPR);

[0015] The data source of the satellite-borne radar FY3-G / PMR is set to use the Fengyun-3G precipitation measurement radar;

[0016] The data source for setting up the ground-based weather radar adopts the basic data of a single ground-based weather radar (S, C, X band) that has undergone quality control.

[0017] In one or more embodiments, preferably, performing data quality control according to the data sources of the spaceborne radar and the ground-based weather radar to form a corrected data source specifically includes:

[0018] For spaceborne radar GPM / DPR data, reduce the data source whose quality does not meet the preset level;

[0019] The S-band and C-band data of Doppler weather radar are quality controlled by noise point filtering, fault image recognition, electromagnetic interference echo recognition, ground object / super-refractive echo recognition, wave echo recognition and velocity deblurring. H -K DP The comprehensive correction method is used to correct the echo intensity attenuation and complete the correction of the ground-based weather radar.

[0020] In one or more embodiments, preferably, matching and comparing the reflectivity factors of the spaceborne radar GPM / DPR and the ground-based weather radar according to the corrected data source to form the optimal pairing data specifically includes:

[0021] The reflectivity factor of the spaceborne radar and the reflectivity factor of the ground-based radar are obtained through time matching, space matching and digital matching;

[0022] Calculating the correlation coefficient using the first calculation formula according to the reflectivity factor of the spaceborne radar and the reflectivity factor of the ground-based radar;

[0023] Calculate the average deviation using the second calculation formula;

[0024] Calculate the standard deviation using the third calculation formula;

[0025] After the original pairing of satellite-to-ground radar reflectivity factors is successful, the overlap area between the two scans is screened to find the reflectivity factors greater than 1000 km. 2 The precipitation echo of is considered as a valid pairing event;

[0026] Establish screening and comparison conditions for effective matching events;

[0027] Among them, the screening and comparison conditions include: the first condition: control the quality of satellite-borne radar data products, and the overall quality is excellent; the second condition: eliminate the paired data with clutter interference at the bottom of the satellite-borne radar; the third condition: the average value threshold limit of the satellite-to-ground radar reflectivity factor, dBZ DPR ≥18dBZ,dBZ GR ≥15dBZ; Fourth condition: control the quality of satellite-borne radar data products, that is, the quality of precipitation type products and bright band products are both excellent; Fifth condition: the threshold of echo filling coverage rate of satellite-ground radar pairing space is equal to 100%; Sixth condition: the radial distance of satellite-ground radar pairing space from the center point of ground-based radar is controlled at 25-200km for S band, 25-150km for C band, and 25-100km for X band; Seventh condition: the paired data is stratus precipitation; Eighth condition: select paired data with an altitude below the bright band; Ninth condition: select paired data with no obstruction at the lowest 5 elevation angles (0.5°, 1.5°, 2.4°, 3.4°, 4.3°) of ground-based radar;

[0028] Setting the relationship between the screening conditions, wherein the first, second and third conditions are preprocessing conditions, and the fourth, fifth, sixth, seventh, eighth and ninth conditions are screening comparison conditions. When the fourth, fifth, sixth, seventh, eighth and ninth conditions are met at the same time, the matching point sample data is screened as the optimal pairing data;

[0029] The first calculation formula is:

[0030]

[0031] Where R is the correlation coefficient, dBZ DPR is the matching DPR reflectivity factor value, is the average value of the matched DPR reflectivity factor, N is the number of matched samples, i is the matching sample number, dBZ GR is the matching ground-based radar reflectivity factor value, is the average value of the matched ground-based radar reflectivity factor;

[0032] The second calculation formula is:

[0033]

[0034] Among them, Bias is the average deviation;

[0035] The third calculation formula is:

[0036]

[0037] Where Std_bias is the standard deviation, and x is the difference between the DPR and the ground-based radar reflectivity factor in dB.

[0038] In one or more embodiments, preferably, the establishment of a fused networked radar consistency assessment algorithm determines an alarm list and forms a problem level, specifically including:

[0039] Combined with the actual echo difference of ground-based weather radar, the three indicators of average deviation, standard deviation and correlation of echo intensity data on equidistant lines in the overlapping area of ​​adjacent radars are used to formulate the consistency evaluation standard of ground-based weather radar, wherein the evaluation standard includes: 1) when av≤3, std≤5 and R2≥0.5 are met at the same time, it is considered credible; 2) when 3<av≤5, 5<std≤8 and 0.3≤R2<0.5 are met, it is considered suspicious; 3) when av>5, std>8 and R2<0.3 are met, it is considered suspicious, wherein av is the average deviation, std is the standard deviation and R2 is the correlation coefficient;

[0040] Obtain the correlation coefficient of the optimal pairing data of the single-station spaceborne radar GPM / DPR and ground-based radar reflectivity factor, and determine whether it is less than the preset value. If it is less than, it is considered to be abnormal data and added to the blacklist. Otherwise, it is considered that the station has good consistency between the satellite and the ground;

[0041] Determine whether STD is less than the preset value. If so, the site is stable. Otherwise, it is added to the blacklist and graylist.

[0042] Determine the average deviation of the site. If the deviation is within the threshold, add it to the whitelist; otherwise, add it to the graylist.

[0043] Add blacklist, greylist and blacklist data to the alarm list;

[0044] The specific evaluation criteria are as follows: for S-band ground-based weather radar, the correlation coefficient threshold is 0.6, the standard deviation threshold is 4dB, and the average deviation threshold is [-5.5dB, 2.5dB]; for C-band and X-band ground-based weather radars, the correlation coefficient threshold is 0.5, the standard deviation threshold is 5dB, and the average deviation threshold is determined according to the probability distribution of a single band to ensure that 70% of the sites of a single-band ground-based radar are on the whitelist;

[0045] The alarm analysis table is set up by integrating the results of the ground-based radar networking consistency verification algorithm based on space-borne radar and the results of the adjacent radar echo intensity consistency detection algorithm, combined with the maintenance and upgrade information of the ground-based weather radar.

[0046] For sites on the monthly blacklist or black-graylist, determine the problem level based on the pre-set alarm analysis table;

[0047] For sites on the annual blacklist or black-graylist, determine the problem level based on the pre-set alarm analysis table;

[0048] For grey-listed sites, the problem level is determined based on the pre-set overall average deviation analysis table.

[0049] In one or more embodiments, preferably, the standard comparison of the ground-based radar reflectivity factor to form a matching result of the standard database and the new space-borne radar FY3-G / PMR specifically includes:

[0050] Extracting the standard database of the ground-based radar reflectivity factor and matching it with the data of the space-borne radar FY3-G / PMR;

[0051] Specifically, the standard database of ground-based radar reflectivity factors is a white list and a revised grey list;

[0052] Add matching of bands corresponding to the reflectivity factors of S band, C band and X band, and use the matching results as the matching results of the standard database.

[0053] In one or more embodiments, preferably, the setting of evaluation categories to form and store evaluation results of the matching results of the standard database and the new spaceborne radar FY3-G / PMR under different categories specifically includes:

[0054] Multiple groups were classified by site, province, radar type, month, altitude, precipitation intensity and frequency;

[0055] The evaluation results corresponding to different stations, provinces, radar types, months, altitudes, precipitation intensity and frequency are displayed and stored according to the classification;

[0056] The overall evaluation results of all spaceborne radars and ground-based radars are displayed and stored according to the evaluation indicators.

[0057] According to a second aspect of an embodiment of the present invention, a system for jointly verifying reflectivity factors of spaceborne and multi-band ground-based radars is provided.

[0058] In one or more embodiments, preferably, the satellite-borne and multi-band ground-based radar reflectivity factor joint verification system includes:

[0059] A data source determination module is used to set the data source of the spaceborne radar and the ground-based weather radar;

[0060] A data quality control module, used to perform data quality control according to the data sources of the spaceborne radar and the ground-based weather radar to form a corrected data source;

[0061] The matching and comparison module is used to match and compare the reflectivity factors of the space-borne radar GPM / DPR and the ground-based weather radar according to the corrected data source to form the optimal matching data;

[0062] The consistency fusion module is used to establish a fused network radar consistency assessment algorithm to determine the alarm list and form a problem level;

[0063] Standard comparison module, used to compare the reflectivity factor of ground-based radar and form the matching result between the standard database and the new space-borne radar FY3-G / PMR;

[0064] The authenticity assessment module is used to set the assessment categories, form a standard database and store the assessment results of the new spaceborne radar FY3-G / PMR in different categories.

[0065] According to a third aspect of an embodiment of the present invention, there is provided a computer-readable storage medium on which computer program instructions are stored. When the computer program instructions are executed by a processor, the method as described in any one of the first aspect of the embodiment of the present invention is implemented.

[0066] According to a fourth aspect of an embodiment of the present invention, there is provided an electronic device, comprising a memory and a processor, wherein the memory is used to store one or more computer program instructions, wherein the one or more computer program instructions are executed by the processor to implement any one of the methods described in the first aspect of the embodiment of the present invention.

[0067] The technical solution provided by the embodiments of the present invention may have the following beneficial effects:

[0068] In the solution of the present invention, the two perspectives of satellite-ground comparison and ground-to-ground comparison are integrated to establish a fused Chinese network radar consistency assessment algorithm, classify, grade and correct ground-based weather radar data, and cover the three bands of S, C, and X to generate a ground-based weather radar standard database and problem list.

[0069] In the scheme of the present invention, by establishing a fused networked radar consistency evaluation algorithm, the reflectivity factor data of multi-band ground-based weather radar is quality controlled, classified, graded and corrected, providing a reference for the application of ground-based radar networking data and numerical model assimilation, and establishing a ground-based weather radar standard database to verify the data quality of FY-3G / PMR, reduce the error of ground verification sources, and provide a basis for the improvement of satellite algorithm products.

[0070] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0071] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0073] Figure 1 The present invention is a flowchart of an embodiment of a method for joint verification of reflectivity factors of spaceborne and multi-band ground-based radars.

[0074] Figure 2 It is a flow chart of setting data sources of spaceborne radar and ground-based weather radar in one embodiment of the present invention.

[0075] Figure 3It is a flow chart of performing data quality control according to the data sources of the satellite-borne radar and the ground-based weather radar to form a corrected data source in one embodiment of the present invention.

[0076] Figure 4 It is a flowchart of matching and comparing the reflectivity factors of the spaceborne radar GPM / DPR and the ground-based weather radar according to the corrected data source to form the optimal pairing data in one embodiment of the present invention.

[0077] Figure 5 It is a flowchart of establishing a fused network radar consistency assessment algorithm to determine an alarm list and form a problem level in one embodiment of the present invention.

[0078] Figure 6 It is a flow chart of performing standard comparison on the reflectivity factor of ground-based radar and forming the matching result of the standard database and the new space-borne radar FY3-G / PMR in one embodiment of the present invention.

[0079] Figure 7 It is a flowchart of setting evaluation categories in one embodiment of the present invention, forming a standard database and storing evaluation results of the new spaceborne radar FY3-G / PMR under different categories.

[0080] Figure 8 It is a structural diagram of a joint verification system for satellite-borne and multi-band ground-based radar reflectivity factors according to an embodiment of the present invention.

[0081] Fig. 9 It is the quality identification process of the two methods: star-to-ground comparison and ground-to-ground comparison. DETAILED DESCRIPTION

[0082] In an embodiment of the present invention, a method and system for joint verification of reflectivity factors of satellite-borne and multi-band ground-based radars are provided. The scheme matches and compares the reflectivity factors of multi-band ground-based weather radars (S, C, and X bands) and satellite-borne radars GPM / DPR, establishes algorithms for matching ground-to-ground radar reflectivity factors and satellite-to-ground radar reflectivity factors, thereby establishing a fused networked radar consistency assessment algorithm, and verifies the reflectivity factor data of ground-based weather radars, generating a standard database and a list of problems for ground-based weather radars; based on the standard database of ground-based weather radars, the authenticity verification of the reflectivity factors of new satellite-borne radars FY3-G / PMR is carried out using the satellite-to-ground radar reflectivity factor matching algorithm, forming a set of joint verification methods and systems for reflectivity factors of satellite-borne and multi-band ground-based radars.

[0083] According to a first aspect of an embodiment of the present invention, a method for jointly verifying reflectivity factors of spaceborne and multi-band ground-based radars is provided. Figure 1 As shown, the joint verification method of the reflectivity factor of the spaceborne and multi-band ground-based radars includes:

[0084] S101, setting the data sources of the spaceborne radar and the ground-based weather radar;

[0085] S102, performing data quality control according to the data sources of the satellite-borne radar and the ground-based weather radar to form a corrected data source;

[0086] S103, matching and comparing the reflectivity factors of the spaceborne radar GPM / DPR and the ground-based weather radar according to the corrected data source to form optimal matching data;

[0087] S104, establishing a fused network radar consistency assessment algorithm to determine an alarm list and form a problem level;

[0088] S105, perform standard comparison on the reflectivity factor of ground-based radar to form the matching result between the standard database and the new space-borne radar FY3-G / PMR;

[0089] S106, setting evaluation categories, forming and storing evaluation results of the matching results of the standard database and the new satellite-borne radar FY3-G / PMR under different categories.

[0090] In the embodiment of the present invention, the prior art does not systematically evaluate and grade the emissivity factor of ground-based weather radar from the perspectives of ground-based observation and space-based observation. The study of ground-based observation alone will be affected by the lack of a unified reference standard, and the study of space-based observation alone will be affected by the small sample size and large randomness. By integrating the two perspectives of satellite-ground comparison and ground-to-ground comparison, a fused networked radar consistency evaluation algorithm is established, ground-based weather radar data is classified, graded and corrected, and a ground-based weather radar standard database and problem list are generated.

[0091] There is an urgent need to verify the authenticity of the reflectivity factor of the second-level product of my country's first precipitation star FY3-G / PMR. Previous studies on similar precipitation stars (GPM / DPR, TRMM / PR) have not systematically carried out on the S, C, and X bands. The three-band ground-based radars have their own advantages, and multi-band ground-based radars can cover the whole country, which requires further research.

[0092] like Figure 2 As shown, in one or more embodiments, preferably, the data sources of the satellite-borne radar and the ground-based weather radar are set, specifically including:

[0093] S201, set the satellite-borne radar GPM / DPR data source to use the Global Precipitation Satellite (GPM) Dual Frequency Rainfall Radar (DPR);

[0094] S202, set the satellite-borne radar FY3G / PMR data source to use the Fengyun-3G satellite precipitation measurement radar;

[0095] S203. The data source of the ground-based weather radar is set to use the basic data of a single ground-based weather radar (S, C, X band) that has undergone quality control.

[0096] In the embodiment of the present invention, the data source of the satellite-borne radar data and the data source of the ground-based weather radar are determined, which specifically include the following parts: 1) Satellite-borne radar GPM / DPR data source: The Global Precipitation Satellite (GPM) dual-frequency rain measuring radar (DPR) is used, and 2Aku V07 product data is used. A product file is generated for about 1.5 hours. The runtime trajectory can be obtained in combination with the Longitude, Latitude, and ScanTime data sets in the product file. The scanning mode used is FS, and the data set is the reflectivity factor after attenuation correction ['FS']['SLV']['zFactorFinal']. The vertical height uses the layer of data closest to the ground (the corresponding data level is 176 layers). 2) Satellite radar FY3G / PMR data source: Adopts China's first precipitation satellite Fengyun-3G precipitation measurement radar (PMR), uses product Ku-band precipitation rate data, 13-15 orbits per day product file, the running sequence trajectory can be obtained in combination with the Geo_Fields data set in the product file, the reflectivity factor after attenuation correction is ['SLV']['zFactorCorrected'], and the vertical height uses the near-surface height. Compared with GPM / DPR 2Aku V07, the reflectivity factor data adds frequency correction modules ['FRE']['zFactorFrequencyCorrectionS'], ['FRE']['zFactorFrequencyCorrectionC'], ['FRE']['zFactorFrequencyCorrectionX']. 3) Multi-band ground-based weather radar data source: Adopts China's new generation Doppler weather radar (S, C band) single-station quality-controlled basic data products, one file every 6 minutes. Volume scanning mode VCP21 completes volume scanning at 9 elevation angles every 6 minutes, and uses reflectivity factor data matching and evaluation; uses the quality-controlled basic data products of China's X-band ground-based weather radar single station, one file every 3-5 minutes, volume scanning, and uses reflectivity factor data matching and evaluation. Specifically, the differences between satellite-to-ground radar and ground-to-ground radar data include: ① Different bands, ground-based radars work in S-band, C-band, and X-band, and GPM / DPR and FY3-G / PMR work in Ku-band. ② Different time resolutions, the time resolution of S-band and C-band ground-based radars is 6 minutes, the time resolution of X-band ground-based radars is 3-5 minutes, GPM / DPR is about 1.5 hours, and FY3-G / PMR is 1.6-1.9 hours. ③ The sampling volume (effective irradiation volume) is different.The radial resolution of the sampling volume of the S-band ground-based radar is 250m, the radial resolution of the sampling volume of the C-band ground-based radar is 150m, and the radial resolution of the sampling volume of the X-band ground-based radar is 75m. The beam width is 0.98°, and the sampling volume increases with the distance. The horizontal resolution of GPM / DPR is 5km, the vertical resolution is 0.125km, and the horizontal resolution of FY3-G / PMR is 5km, and the vertical resolution is 0.050km. ④ The influence of attenuation and ground objects is different. Ground objects have a greater impact on ground-based radars, and fixed ground object echoes, super-refractive ground object echoes and beam blocking will appear. The impact of attenuation on S-band ground-based radars can be ignored, but it has a greater impact on C-band and X-band ground-based radars, GPM / DPR and FY3-G / PMR.

[0097] like Figure 3 As shown, in one or more embodiments, preferably, performing data quality control according to the data sources of the satellite-borne radar and the ground-based weather radar to form a corrected data source specifically includes:

[0098] S301. For spaceborne radar GPM / DPR data, reduce the data source whose quality does not meet the preset level;

[0099] S302: Doppler weather radar S-band data and C-band data are quality controlled by noise point filtering, fault image recognition, electromagnetic interference echo recognition, ground object / super-refraction echo recognition, wave echo recognition and velocity deblurring. H -K DP The comprehensive correction method is used to correct the echo intensity attenuation and complete the correction of the ground-based weather radar.

[0100] In the embodiment of the present invention, the specific data quality control process includes two steps: 1) Spaceborne radar quality control: For the spaceborne radar GPM / DPR data, use ['FS']['FLG']['qualityFlag'] to control the data quality, ['FS'][attr_key]['qualityBB'] to control the quality of the bright band product, and ['FS'][attr_key]['qualityTypePrecip'] to control the quality of the precipitation type classification product; for the spaceborne radar FY3-G / PMR data, use ['SLV']['qualitySLV'] to control the data quality, and ['CSF']['flagBB'] to control the quality of the bright band product. 2) Multi-band ground-based weather radar quality control: For the new generation of Doppler weather radar (S band, C band) data, quality control is performed through noise point filtering, fault bad image recognition, electromagnetic interference echo recognition, ground object / super refraction echo recognition, wave echo recognition, velocity deblurring, etc., among which the C-band ground-based radar also performs attenuation correction. For the ground-based radar X-band data, by using Z H -K DP The comprehensive correction method is used to correct echo intensity attenuation.

[0101] like Figure 4 As shown, in one or more embodiments, preferably, matching and comparing the reflectivity factors of the spaceborne radar GPM / DPR and the ground-based weather radar according to the corrected data source to form the optimal pairing data specifically includes:

[0102] S401, obtaining the reflectivity factor of the spaceborne radar and the reflectivity factor of the ground-based radar through time matching, space matching and digital matching;

[0103] S402, calculating a correlation coefficient using a first calculation formula according to the reflectivity factor of the spaceborne radar and the reflectivity factor of the ground-based radar;

[0104] S403, calculating the average deviation using a second calculation formula;

[0105] S404, calculating the standard deviation using a third calculation formula;

[0106] S405. After the original pairing of the satellite-to-ground radar reflectivity factors is successful, the precipitation echoes with an area greater than 1000 km2 in the overlapping area of ​​the two scans are screened and considered as valid pairing events;

[0107] S406, establishing screening and comparison conditions for valid pairing events;

[0108] S407, wherein the screening and comparison conditions include: first condition: control the quality of satellite-borne radar data products, and the overall quality is excellent; second condition: remove the paired data with clutter interference at the bottom of the satellite-borne radar; third condition: the average value threshold limit of the satellite-to-ground radar reflectivity factor, dBZDPR ≥ 18dBZ, dBZGR ≥ 15dBZ; fourth condition: control the quality of satellite-borne radar data products, that is, the quality of precipitation type products and bright band products are both excellent; fifth condition: the space echo of the satellite-to-ground radar pairing is full of coverage The coverage rate thresholds are all equal to 100%; the sixth condition: the radial distance between the satellite-to-ground radar pairing space and the center point of the ground-based radar is controlled at 25-200km for the S band, 25-150km for the C band, and 25-100km for the X band; the seventh condition: the paired data is stratus precipitation; the eighth condition: select paired data with an altitude below the bright band; the ninth condition: select paired data with no obstruction at the lowest 5 elevation angles (0.5°, 1.5°, 2.4°, 3.4°, 4.3°) of the ground-based radar;

[0109] S408, setting the relationship between the screening conditions, wherein the first, second and third conditions are preprocessing conditions, and the fourth, fifth, sixth, seventh, eighth and ninth conditions are screening and comparison conditions, and when the fourth, fifth, sixth, seventh, eighth and ninth conditions are met at the same time, the matching point sample data is screened as the optimal pairing data;

[0110] The first calculation formula is:

[0111]

[0112] Where R is the correlation coefficient, dBZ DPR is the matching DPR reflectivity factor value, is the average value of the matched DPR reflectivity factor, N is the number of matched samples, i is the matching sample number, dBZ GR is the matching ground-based radar reflectivity factor value, is the average value of the matched ground-based radar reflectivity factor;

[0113] The second calculation formula is:

[0114]

[0115] Among them, Bias is the average deviation;

[0116] The third calculation formula is:

[0117]

[0118] Where Std_bias is the standard deviation, and x is the difference between the DPR and the ground-based radar reflectivity factor in dB.

[0119] In the embodiment of the present invention, specifically, the matching and comparison process includes time, space and numerical matching; and then the optimal pairing database of satellite-to-ground radar reflectivity factors is generated based on the matching results. In the time matching process, the start time and end time of the satellite passing the ground-based radar coverage are calculated, and the middle time of the transit = (end time of the transit - start time of the transit) / 2 + start time of the transit. For the S, C, and X-band ground-based radars, the ground-based radar data closest to the middle time of the transit within the ±5min time period of the satellite transit are selected for matching. The spatial matching adopts the geometric matching method, and matches the area where the satellite-borne radar and ground-based radar beams overlap in units of effective irradiation volume, and calculates the average satellite-borne radar reflectivity factor value and the ground-based radar reflectivity factor value at the geometric intersection of the satellite-borne radar scanning beam and each ground-based radar elevation scan. The resolution of the satellite radar in the horizontal direction of the matching point is low. The horizontal resolution of each matching point is 5km of the GPM / DPR sub-satellite point. According to the horizontal beam coverage of GPM / DPR, the radial library set of the ground-based radar is obtained. The resolution of the ground-based radar in the vertical direction is low. The vertical resolution of each matching point is the beam thickness of the matching point (vertical beam coverage). According to the vertical beam coverage of the ground-based radar, the DPR radial library set is obtained. In the numerical matching process, the frequency correction and average value calculation are completed, including: 1) The frequency correction is: within the reasonable drop spectrum parameter range, set the parameter μ = 0, 2, 4, the temperature T = 0, 10, 15, 20℃, the rainfall is equal to 0.1 to 199.9mm-1, and increase by 0.1mm-1. The frequency correction relationship is established to generate the reflectivity factor (dBZ) and Z lookup table of Ku and S bands. After the DPR and S-band ground-based radar are matched, the position closest to the reflectivity factor value of the DPR Ku-band is found in the lookup table, and the reflectivity factor frequency of the DPR Ku-band is corrected to the S-band reflectivity factor corresponding to this position. For C-band and X-band ground-based radars, the calculation of the radar reflectivity factor Z value under Rayleigh scattering is abandoned, and the equivalent reflectivity factor Ze is calculated using Mie scattering. 2) The average value is calculated as follows: After obtaining the matched library set, the invalid values ​​of the DPR and ground-based radar data are eliminated, and the valid values ​​are obtained for subsequent average value calculation. Specific invalid values: S- and C-band ground-based radars are -32768, -1280, -999, -999.9, and -33, and X-band ground-based radars are -994, -995, -996, -997, and -998. The specific average value calculation formula is: average value = sum of all valid values / number of all matched libraries.In the horizontal direction, for the radial distance library set matched on the ground-based radar, the reflectivity factor value at each distance library is converted from dBZ to Z (dBZ = 10log (Z)), the average value is calculated, and the average value is converted to dBZ again, as the reflectivity factor of the ground-based radar at this position (the average value of the matching space); in the vertical direction, for the radial (vertical) distance library set of DPR in this area, the reflectivity factor value at each distance library is converted from dBZ to Z (dBZ = 10log (Z)), the average value is calculated, and the average value is converted to dBZ again, as the reflectivity factor of the satellite-borne radar at this position (the average value of the matching space). Among them, the screening and comparison conditions include: the first condition: controlling the quality of the satellite-borne radar data product, and the overall quality is excellent. Using the parameter ['FS']['FLG']['qualityFlag'] of the satellite-borne radar GPM / DPR at the matching point, if this parameter is equal to 0, it means that the overall quality of the satellite-borne radar GPM / DPR data product at the matching point is excellent. The second condition: eliminating the paired data with clutter interference at the bottom of the satellite-borne radar. The parameter ['FS']['PRE']['binClutterFreeBottom'] of the spaceborne radar GPM / DPR is used. This parameter indicates the number of bins with clutter interference at the bottom of the spaceborne radar, that is, the maximum height. If the height of the matching point is below this height, the matching point sample data is removed. The third condition: the threshold limit of the average value of the reflectivity factor of the satellite-to-ground radar, dBZDPR ≥ 18dBZ, dBZGR ≥ 15dBZ. The fourth condition: control the quality of the spaceborne radar data product, that is, the quality of the precipitation type product and the quality of the bright band product are both excellent. The parameter ['FS'][attr_key]['qualityTypePrecip'] of the matching point spaceborne radar GPM / DPR is used. This parameter indicates the quality of the precipitation type product. When it is equal to 1, it means that the quality of the precipitation type product is excellent, and the parameter ['FS'][attr_key]['qualityBB'] of the matching point spaceborne radar GPM / DPR is used. This parameter indicates the quality of the bright band product. When it is equal to 1, it means that the quality of the bright band product is excellent. When the quality of the precipitation type product and the quality of the bright band product at the matching point are both excellent, the matching point is selected, otherwise the matching point is eliminated. The fifth condition: The echo filling coverage threshold of the satellite-to-ground radar pairing space is equal to 100%. In order to analyze the impact of echo filling in the matching space on the results, the echo coverage f of the ground-based radar and GPM / DPR is defined in the matching space, which is the number of libraries with echoes divided by the total number of libraries in the match. Set the minimum threshold of echo coverage fmin, and select matching samples that satisfy f≥fmin for both the ground-based radar and GPM / DPR. Here, fmin is set to 100%, and only matching samples with echo coverage equal to 100%, that is, completely filled, are selected. The sixth condition: The radial distance of the satellite-to-ground radar pairing space from the center point of the ground-based radar is controlled at 25-200km for the S band, 25-150km for the C band, and 25-100km for the X band.Seventh condition: The paired data is stratiform precipitation. Using the parameter ['FS'][attr_key]['typePrecip'] of the spaceborne radar GPM / DPR, when this parameter is ≥ 10,000,000 and < 20,000,000, it indicates stratiform precipitation. Eighth condition: Select the paired data with the height below the bright band. Using the parameter ['FS'][attr_key]['binBBBottom'] of the spaceborne radar GPM / DPR, this parameter represents the height of the bottom of the bright band. If the central height of the matching point is below this height, then select the sample data of this matching point. Ninth condition: Select the paired data without obstruction at the lowest 5 elevation angles (0.5°, 1.5°, 2.4°, 3.4°, 4.3°) of the ground-based radar.

[0120] As Figure 5 shown, in one or more embodiments, preferably, the established fusion networking radar consistency evaluation algorithm determines an alarm list and forms a problem level, specifically including:

[0121] S501. Combining the actual echo difference situation of the ground-based weather radar, using three indicators of the average deviation, standard deviation, and correlation of the echo intensity data on the equidistant line in the overlapping area of adjacent radars to formulate the consistency evaluation standard for the ground-based weather radar. Among them, the evaluation standard includes: 1) When av ≤ 3, std ≤ 5, and R2 ≥ 0.5 are all satisfied, it is considered credible; 2) When one of 3 < av ≤ 5, 5 < std ≤ 8, and 0.3 ≤ R2 < 0.5 is satisfied, it is considered suspicious; 3) When one of av > 5, std > 8, and R2 < 0.3 is satisfied, it is considered doubtful. Among them, av is the average deviation, std is the standard deviation, and R2 is the correlation coefficient;

[0122] S502. Obtain the correlation coefficient of the optimal paired data of the single-station spaceborne radar GPM / DPR and the ground-based radar reflectivity factor, and judge whether it is less than the preset value. If it is less than, it is considered abnormal data and added to the blacklist. Otherwise, it is considered that the space-ground consistency of this site is good;

[0123] S503. Judge whether STD is less than the preset value. If it is less than, the site is stable. Otherwise, it is added to the black and gray list;

[0124] S504. Judge the average deviation of the site. If the deviation is within the threshold, it is added to the white list. Otherwise, it is added to the gray list;

[0125] S505, add the black-gray list, gray list and blacklist data to the alarm list; the specific evaluation criteria are as follows: for S-band ground-based weather radar, the correlation coefficient threshold is 0.6, the standard deviation threshold is 4dB, and the average deviation threshold is [-5.5dB, 2.5dB]; for C-band and X-band ground-based weather radars, the correlation coefficient threshold is 0.5, the standard deviation threshold is 5dB, and the average deviation threshold is determined according to the probability distribution of a single band to ensure that 70% of the single-band ground-based radar stations are on the white list;

[0126] S506. An alarm analysis table is set by integrating the results of the ground-based radar network consistency verification algorithm based on the space-borne radar and the results of the adjacent radar echo intensity consistency detection algorithm, combined with the ground-based weather radar maintenance and upgrade information.

[0127] S507, judging the problem level according to a preset alarm analysis table for the monthly scale blacklist or black-graylist site;

[0128] S508, judging the problem level according to a preset alarm analysis table for the annual scale blacklist or black-graylist site;

[0129] S509: For the grey list sites, determine the problem level according to a preset overall average deviation analysis table.

[0130] In an embodiment of the present invention, first, ground-based radars of the same band perform consistency detection of echo intensity of adjacent radars, and the ground-based radars of the S, C, and X bands perform the detection separately. The specific process is as follows: read the CAPPI grid point data of the same contour surface of adjacent radars at the same time, find the echo overlapping area, and calculate the equidistant line with equal distance to the two radars in the overlapping area (the equidistant line width threshold is adjustable), and finally output the radar echo data on the equidistant line for analysis. The specific steps are as follows: (1) Analyze the single-station radar grid data file after data quality control and before puzzle, and read the CAPPI data of the two radars at the same time; (2) Read the station longitude and latitude values ​​and the number of longitude and latitude grid points in the data file, and number the grid data with longitude and latitude; (3) Traverse the generated data to determine the same observation area of ​​the two radars; (4) In order to reduce the influence of beam broadening and distance attenuation, use the distance formula to find the set of points in the same observation area with equal distances to the two radars, that is, equidistant lines; (5) Determine the width of the equidistant line (the threshold is adjustable) and eliminate abnormal echoes to obtain the echo data that can be used for adjacent radar consistency analysis.

[0131] Specifically, the consistency evaluation criteria are shown in Table 1;

[0132] Table 1 Evaluation criteria for consistency of adjacent radar echo strengths

[0133]

[0134] Secondly, the ground-based radar network consistency test algorithm based on spaceborne radar is carried out for ground-based radars in the same band, and the ground-based radars in the S, C, and X bands are carried out separately. Taking the uniform and stable precipitation star GPM as the reference standard, by comparing the comparison results of precipitation star and ground-based radar networking, the consistency standard is formulated according to the overall situation to evaluate the consistency between ground-based radars. Since they are the same data source for comparison, the evaluation results of the algorithm are trustworthy and have comparison value. The evaluation index is calculated based on the optimal pairing data of the reflectivity factor of the satellite-to-ground radar at each station, and the quality judgment is added to the ground-based radar according to the evaluation index.

[0135] White list: the reflectivity factor of satellite-to-ground radar has good consistency, the ground-based radar is stable and has good networking consistency, and there is no problem with the data of this type of ground-based radar during the evaluation period; Black list: 1 type of alarm list, the reflectivity factor of satellite-to-ground radar has poor consistency, and there are obvious problems in the evaluation period of this type of ground-based radar; Black-gray list: 1 type of alarm list, the reflectivity factor of satellite-to-ground radar has good consistency but the ground-based radar is not stable enough, and there are problems in the evaluation period of this type of ground-based radar; Gray list: 1 type of alarm list, the reflectivity factor of satellite-to-ground radar has good consistency, the ground-based radar is stable but has poor networking consistency, and this type of ground-based radar needs calibration or data correction.

[0136] The consistency evaluation algorithm and scheme of China's networked radars that integrate ground-based radars in the same band are conducted separately for the three bands of S, C, and X. Considering the frequency of satellite transit and precipitation, the ground-based radar network consistency verification algorithm based on spaceborne radar is suitable for the time scale of month and above. If the time scale is too short, the sample size is insufficient and the randomness is strong; and the consistency detection algorithm of adjacent radar echo intensity is a comparison between ground-based radars and ground-based radars, and there is no unified reference standard, so the results may be offset. Therefore, the two algorithms are integrated to complement each other.

[0137] If there are problems with the data of the stations on the alarm list, further confirmation is required to determine whether they are key focus stations, and feedback is given to the stations for verification or calibration correction. The results of the adjacent radar echo intensity consistency detection algorithm and the ground-based radar network consistency verification algorithm based on space-borne radar are integrated with the maintenance and upgrade information of ground-based weather radars to establish a highly accurate and applicable Chinese network radar consistency evaluation algorithm and scheme. The evaluation results are given in a cyclic evaluation method, the ground-based radar alarm list is graded, and the quality comprehensive judgment results are given. The specific judgment process is as follows: Fig. 9 shown.

[0138] Taking a single month as an example, the detailed plan and process are as follows: First, give a monthly report for the current month and report the problem stations for the current month. (1) The ground-based radar network consistency check algorithm based on the spaceborne radar obtains the alarm list for the current month; (2) Output the quality judgment given by the adjacent radar echo intensity consistency detection algorithm for the alarm list for the current month. If the quality judgment is suspicious or suspected to be wrong, this type of station is comprehensively judged as the problem station of the current month. If there is no information record of downtime maintenance and upgrade for the problem station of the current month, the problem station needs to be pointed out in the monthly report of the current month, and the feedback station needs to verify the specific problem. Among them, the station judged as a problem station by the gray list needs to calculate the difference between the average deviation of the station and the overall average deviation of the same band in China and the difference between the average deviation of the same band in the province. The specific data is given in the monthly report for reference of radar calibration or data correction.

[0139] Secondly, when giving the monthly report of the current month, a list of key concerns for the previous six months (including the current month) is given. The evaluation indicators and quality judgments of the alarm list for the previous six months (including the current month) are calculated back, as well as the quality judgments of the previous six months given by the consistency detection algorithm of the echo intensity of adjacent radars at each station. According to the results of the previous six months, the radar quality problems (consistency problems) are graded to determine whether they are marked as key concern sites, and the types of radar problems are qualitatively described. (1) For blacklist or black-graylist sites, the quality problems are graded according to the standards in Table 2, which are divided into Level I, Level II, Level III, Level IV, and Level V. The lower the level, the more serious the problem. Level I, Level II, and Level III are marked as key concern sites. If there is no information record of downtime maintenance and upgrades during this period, the site needs to report the station verification problem, otherwise the log record is tracked and observed; Level IV and Level V are marked as non-key concern sites, and the log record is tracked and observed. The proportions in Tables 2 and 4 are valid proportions. The alarm ratio P1 is the ratio of the frequency of the alarm list of a certain station to the frequency of the quality identification results. For example, if a station has 3 alarm lists in a year and 10 months of quality identification, the alarm ratio is 3 / 10. The adjacent radar echo intensity consistency detection algorithm gives a suspicious or suspected error ratio P2, which is the frequency ratio of the quality identification of a certain station as suspicious or suspected error to the frequency ratio of the quality identification results. For example, if the adjacent radar echo intensity consistency detection algorithm of a certain station gives a suspicious or suspected error quality identification 25 times in a year and has a quality identification result 50 times, the adjacent radar echo intensity consistency detection algorithm gives a suspicious or suspected error ratio of 1 / 2.

[0140] Table 2: Quality problem grading standards for blacklist or black-graylist sites

[0141]

[0142]

[0143] (2) For the gray list stations, calculate the difference between the average deviation of the previous 6 months (including the current month) and the overall average deviation of the same band in China, as well as the difference between the overall average deviation of the same band in the province. According to the standards in Table 3, the consistency grade scores of the station compared with China and the province are calculated respectively. The sum of the two scores is the consistency grade score. For example, the difference of Yueyang Station compared with China in 2021 is -4.72 to -3.63, and the difference compared with the province is -4.50 to -2.20. The consistency grade score compared with China is 2, the consistency grade score compared with the province is 2, and the consistency grade score of the station is 4. According to the consistency grade score, the consistency problem level is divided into Level I (4 points), Level II (3 points), Level III (2 points), Level IV (1 point), and Level V (0 points). The lower the level, the more serious the problem. Level I and Level II are marked as key focus sites. If there is no record of downtime for maintenance and upgrades during this period, the site needs to feedback the station verification problem, otherwise the log record will be followed up and observed. Level III, IV, and V are marked as non-key focus sites and the log record will be followed up and observed.

[0144] For grey-listed sites, the grade score is determined based on a pre-set overall average deviation analysis table.

[0145] Table 3 Greylist site consistency problem level score standard

[0146] Difference Qualitative description Level score Always greater than 0 and the minimum value is ≥ 2 Abnormally large 2 Always greater than 0 and 0<minimum value<2 Too big 1 There are positive and negative General (normal) 0 Always less than 0 and the maximum value is ≤ -2 Abnormally small 2 Always less than 0 and 0<maximum value ≤-2 Small 1

[0147] If the consistency evaluation results of China's ground-based weather radars are given on an annual scale, the results of the previous 12 months (including the current month) need to be calculated when marking the focus list, and the standards in Table 2 should be replaced by those in Table 4. The rest of the process remains unchanged, and the quality issues (consistency issues) are graded. The evaluation of other time scales can refer to the standards given on the monthly and annual scales.

[0148] Table 4: Quality problem grading standards for blacklist or black-graylist sites

[0149]

[0150]

[0151] The standards of Table 2, Table 3 and Table 4 are applicable to S-band, C-band and X-band. The alarm list specifically refers to the problem sites identified by the ground-based radar network consistency verification algorithm of the spaceborne radar; the focus list is the fusion of the Chinese network radar consistency assessment algorithm and scheme, which classifies the quality problems (consistency problems) of the alarm list and comprehensively judges the sites with serious problems.

[0152] Based on the above evaluation results, a standard radar database was developed. The specific development standards are as follows: (1) The stations and their base data reflectivity factors whose quality judgment is on the white list during the evaluation period; (2) The stations and their base data reflectivity factors whose quality judgment is on the gray list during the evaluation period and whose comprehensive quality judgment is on the consistency problem level III, IV, and V; (3) The stations whose quality judgment is on the gray list during the evaluation period and whose comprehensive quality judgment is on the consistency problem level I and II, a linear relationship is established between the optimal paired data of the reflectivity factors of the spaceborne radar GPM / DPR and the ground-based radar during the evaluation period, and based on the linear relationship, the base data reflectivity factor is obtained by linearly correcting the ground-based radar reflectivity factor using the spaceborne radar GPM / DPR.

[0153] The principle for obtaining the problem list is to identify the sites whose quality is judged to be on the blacklist or black-gray list during the evaluation period and their base data reflectivity factors.

[0154] Figure 6 It is a flow chart of performing standard comparison on the reflectivity factor of ground-based radar and forming the matching result of the standard database and the new space-borne radar FY3-G / PMR in one embodiment of the present invention.

[0155] like Figure 6 As shown, in one or more embodiments, preferably, the standard comparison of the ground-based radar reflectivity factor to form a matching result of the standard database and the new space-borne radar FY3-G / PMR specifically includes:

[0156] S601, extracting the standard database of the ground-based radar reflectivity factor and matching it with the data of the space-borne radar FY3-G / PMR;

[0157] S602, adding matching of the bands corresponding to the reflectivity factors of the S band, the C band, and the X band, and using the matching results as matching results of the standard database.

[0158] In an embodiment of the present invention, the satellite-borne radar FY3-G / PMR and the standard database of multi-band ground-based weather radar reflectivity factors are matched and compared, and the results of matching the S-band, C-band, and X-band reflectivity factors of the FY3-G / PMR frequency correction module and the corresponding band ground-based radar reflectivity factors are added, wherein the ground-based radar reflectivity factor selects the standard database of the ground-based radar reflectivity factor.

[0159] Figure 7 It is a flowchart of setting evaluation categories in one embodiment of the present invention, forming a standard database and storing evaluation results of the new spaceborne radar FY3-G / PMR under different categories.

[0160] like Figure 7As shown, in one or more embodiments, preferably, the setting of evaluation classification, forming and storing the evaluation results of the standard database and the new satellite-borne radar FY3-G / PMR under different classifications, specifically includes:

[0161] S701, multiple group classification according to site, province, radar type, month, altitude, precipitation intensity and frequency;

[0162] S702, displaying and storing the evaluation results corresponding to different stations, provinces, radar types, months, altitudes, precipitation intensities and frequencies according to the classification;

[0163] S703. Display and store the overall evaluation results of all spaceborne radars and ground-based radars according to the evaluation indicators.

[0164] In an embodiment of the present invention, when the authenticity inspection and evaluation of the reflectivity factor of the satellite-borne radar FY3-G / PMR is carried out using a single-band ground-based radar reflectivity factor standard database, the following 8 points are used. The three bands S, C, and X are carried out in sequence. 1) Overall evaluation: The matching samples of the satellite-borne radar FY3-G / PMR and the Chinese ground-based radar reflectivity factor are used to calculate the overall result according to the evaluation index; at the same time, the matching samples of the satellite-borne radar FY3-G / PMR and the Chinese ground-based radar reflectivity factor standard database are used to calculate the overall result according to the evaluation index. By comparing the differences before and after, the influence of the establishment of the standard database of the ground-based radar reflectivity factor on the authenticity inspection result of the satellite-borne radar FY3-G / PMR reflectivity factor is obtained. 2) Sub-site evaluation: The matching samples of the satellite-borne radar FY3-G / PMR and the Chinese ground-based radar reflectivity factor standard database are used to calculate the results of each station according to the evaluation index, and the evaluation results of each station of the FY3-G / PMR reflectivity factor authenticity inspection are obtained. 3) Evaluation by province: Based on the province to which the ground-based radar site belongs, the matching samples of the spaceborne radar FY3-G / PMR and the standard database of the reflectivity factor of China's ground-based radar are distinguished, and the provincial results are calculated according to the evaluation indicators, and the evaluation results of the authenticity test of the FY3-G / PMR reflectivity factor by province are obtained. 4) Evaluation by radar type: Based on the radar type to which the ground-based radar site belongs, the matching samples of the spaceborne radar FY3-G / PMR and the standard database of the reflectivity factor of China's ground-based radar are distinguished, and the radar type results are calculated according to the evaluation indicators, and the evaluation results of the authenticity test of the FY3-G / PMR reflectivity factor by radar type are obtained. 5) Evaluation by month: Based on the matching samples of the spaceborne radar FY3-G / PMR and the standard database of the reflectivity factor of China's ground-based radar are calculated according to the evaluation indicators, and the monthly results of the authenticity test of the FY3-G / PMR reflectivity factor are obtained. 6) Evaluation by altitude: Based on the altitude of the ground-based radar site, the matching samples of the spaceborne radar FY3-G / PMR and the standard database of the reflectivity factor of the Chinese ground-based radar are used to calculate the results of different altitude intervals according to the evaluation indicators, and the evaluation results of the authenticity test of the FY3-G / PMR reflectivity factor in different altitude intervals of the ground-based radar are obtained. 7) Evaluation by precipitation intensity: Based on the precipitation intensity, the matching samples of the spaceborne radar FY3-G / PMR and the standard database of the reflectivity factor of the Chinese ground-based radar are used to calculate the results of different precipitation intensity intervals according to the evaluation indicators, and the evaluation results of the authenticity test of the FY3-G / PMR reflectivity factor in different precipitation intensity intervals of the ground-based radar are obtained. 8) Evaluation by frequency correction algorithm: Based on the frequency correction algorithm, the matching samples of the spaceborne radar FY3-G / PMR and the standard database of the reflectivity factor of the Chinese ground-based radar are used to calculate the results of different frequency correction algorithms according to the evaluation indicators, and the evaluation results of the authenticity test of the FY3-G / PMR reflectivity factor in different frequency correction algorithms are obtained.The two frequency correction algorithms refer to the algorithm in this design and the algorithm provided by FY3-G / PMR.

[0165] According to a second aspect of an embodiment of the present invention, a system for jointly verifying reflectivity factors of spaceborne and multi-band ground-based radars is provided.

[0166] Figure 8 It is a structural diagram of a joint verification system for satellite-borne and multi-band ground-based radar reflectivity factors according to an embodiment of the present invention.

[0167] In one or more embodiments, preferably, the satellite-borne radar and satellite-borne and multi-band ground-based radar reflectivity factor joint calibration system comprises:

[0168] The data source determination module 801 is used to set the data source of the spaceborne radar and the ground-based weather radar;

[0169] A data quality control module 802 is used to perform data quality control according to the data sources of the spaceborne radar and the ground-based weather radar to form a corrected data source;

[0170] The matching and comparison module 803 is used to match and compare the reflectivity factors of the space-borne radar GPM / DPR and the ground-based weather radar according to the corrected data source to form the optimal matching data;

[0171] The consistency fusion module 804 is used to establish a fused network radar consistency evaluation algorithm to determine the alarm list and form a problem level;

[0172] The standard comparison module 805 is used to perform standard comparison on the reflectivity factor of the ground-based radar to form a matching result between the standard database and the new space-borne radar FY3-G / PMR;

[0173] The authenticity evaluation module 806 is used to set evaluation categories, form and store the evaluation results of the standard database and the new spaceborne radar FY3-G / PMR under different categories.

[0174] In the embodiment of the present invention, a system suitable for different structures is realized through a series of modular designs. The system can achieve closed-loop, reliable and efficient execution through collection, analysis and control.

[0175] The technical solution provided by the embodiments of the present invention may have the following beneficial effects:

[0176] In the solution of the present invention, the two perspectives of satellite-ground comparison and ground-to-ground comparison are integrated to establish a fused Chinese network radar consistency assessment algorithm, classify, grade and correct ground-based weather radar data, and cover the three bands of S, C, and X to generate a ground-based weather radar standard database and problem list.

[0177] In the scheme of the present invention, by establishing a fused networked radar consistency evaluation algorithm, the reflectivity factor data of multi-band ground-based weather radar is quality controlled, classified, graded and corrected, providing a reference for the application of ground-based radar networking data and numerical model assimilation, and establishing a ground-based weather radar standard database to verify the data quality of FY-3G / PMR, reduce the error of ground verification sources, and provide a basis for the improvement of satellite algorithm products.

Claims

1. A joint verification method for reflectivity factors of spaceborne and multi-band ground-based radars, characterized in that: The method includes: Set up data sources for spaceborne radar and ground-based weather radar; Performing data quality control based on the data sources of the spaceborne radar and the ground-based weather radar to form a corrected data source; Match and compare the reflectivity factors of the spaceborne radar GPM / DPR and the ground-based weather radar based on the corrected data source to form the optimal pairing data; Establish a fusion network radar consistency assessment algorithm to determine the alarm list and form a problem level; Conduct standard comparison of ground-based radar reflectivity factors to form matching results between the standard database and the new space-borne radar FY3-G / PMR; Set the evaluation categories, form the matching results of the standard database and the new spaceborne radar FY3-G / PMR under different categories and store them.

2. The method for joint verification of satellite-borne and multi-band ground-based radar reflectivity factors as claimed in claim 1, characterized in that: The data sources of the spaceborne radar and the ground-based weather radar are specifically set up as follows: The satellite-borne radar GPM / DPR data source is set to use the Global Precipitation Satellite (GPM) Dual-frequency Rainfall Radar (DPR); The data source of the satellite-borne radar FY3-G / PMR is set to use the Fengyun-3G precipitation measurement radar; The data source for setting up the ground-based weather radar adopts the basic data of a single ground-based weather radar (S, C, X band) that has undergone quality control.

3. The method for joint verification of satellite-borne and multi-band ground-based radar reflectivity factors as claimed in claim 1, characterized in that: The data quality control is performed according to the data sources of the spaceborne radar and the ground-based weather radar to form a corrected data source, specifically including: For spaceborne radar GPM / DPR data, reduce the data source whose quality does not meet the preset level; The S-band and C-band data of Doppler weather radar are quality controlled by noise point filtering, fault image recognition, electromagnetic interference echo recognition, ground object / super-refractive echo recognition, wave echo recognition and velocity deblurring. H -K DP The comprehensive correction method is used to correct the echo intensity attenuation and complete the correction of the ground-based weather radar.

4. The method for joint verification of satellite-borne and multi-band ground-based radar reflectivity factors as claimed in claim 1, characterized in that: The matching and comparison of the reflectivity factors of the spaceborne radar GPM / DPR and the ground-based weather radar according to the corrected data source to form the optimal pairing data specifically includes: The reflectivity factor of the spaceborne radar and the reflectivity factor of the ground-based radar are obtained through time matching, space matching and digital matching; Calculating the correlation coefficient using the first calculation formula according to the reflectivity factor of the spaceborne radar and the reflectivity factor of the ground-based radar; Calculate the average deviation using the second calculation formula; Calculate the standard deviation using the third calculation formula; After the original pairing of satellite-to-ground radar reflectivity factors is successful, the overlap area between the two scans is screened to find the reflectivity factors greater than 1000 km. 2 The precipitation echo of is considered as a valid pairing event; Establish screening and comparison conditions for effective matching events; Among them, the screening and comparison conditions include: the first condition: control the quality of satellite-borne radar data products, and the overall quality is excellent; the second condition: eliminate the paired data with clutter interference at the bottom of the satellite-borne radar; the third condition: the average value threshold limit of the satellite-to-ground radar reflectivity factor, dBZ DPR ≥18dBZ,dBZ GR ≥15dBZ; Fourth condition: control the quality of satellite-borne radar data products, that is, the quality of precipitation type products and bright band products are both excellent; Fifth condition: the threshold of echo filling coverage rate of satellite-ground radar pairing space is equal to 100%; Sixth condition: the radial distance of satellite-ground radar pairing space from the center point of ground-based radar is controlled at 25-200km for S band, 25-150km for C band, and 25-100km for X band; Seventh condition: the paired data is stratus precipitation; Eighth condition: select paired data with an altitude below the bright band; Ninth condition: select paired data with no obstruction at the lowest 5 elevation angles (0.5°, 1.5°, 2.4°, 3.4°, 4.3°) of ground-based radar; Setting the relationship between the screening conditions, wherein the first, second and third conditions are preprocessing conditions, and the fourth, fifth, sixth, seventh, eighth and ninth conditions are screening comparison conditions. When the fourth, fifth, sixth, seventh, eighth and ninth conditions are met at the same time, the matching point sample data is screened as the optimal pairing data; The first calculation formula is: Where R is the correlation coefficient, dBZ DPR is the matching DPR reflectivity factor value, is the average value of the matched DPR reflectivity factor, N is the number of matched samples, i is the matching sample number, dBZ GR is the matching ground-based radar reflectivity factor value, is the average value of the matched ground-based radar reflectivity factor; The second calculation formula is: Among them, Bias is the average deviation; The third calculation formula is: x=dBZ GR -dBZ DPR Where Std_bias is the standard deviation, and x is the difference between the DPR and the ground-based radar reflectivity factor in dB.

5. The method for joint verification of satellite-borne and multi-band ground-based radar reflectivity factors as claimed in claim 1, characterized in that: The establishment of the fused network radar consistency assessment algorithm determines the alarm list and forms the problem level, specifically including: Combined with the actual echo difference of ground-based weather radar, the three indicators of average deviation, standard deviation and correlation of echo intensity data on equidistant lines in the overlapping area of ​​adjacent radars are used to formulate the consistency evaluation standard of ground-based weather radar, wherein the evaluation standard includes: 1) when av≤3, std≤5 and R2≥0.5 are met at the same time, it is considered credible; 2) when 3<av≤5, 5<std≤8 and 0.3≤R2<0.5 are met, it is considered suspicious; 3) when av>5, std>8 and R2<0.3 are met, it is considered suspicious, wherein av is the average deviation, std is the standard deviation and R2 is the correlation coefficient; Obtain the correlation coefficient of the optimal pairing data of the single-station spaceborne radar GPM / DPR and ground-based radar reflectivity factor, and determine whether it is less than the preset value. If it is less than, it is considered to be abnormal data and added to the blacklist. Otherwise, it is considered that the station has good consistency between the satellite and the ground; Determine whether STD is less than the preset value. If so, the site is stable. Otherwise, it is added to the blacklist and graylist. Determine the average deviation of the site. If the deviation is within the threshold, add it to the whitelist; otherwise, add it to the graylist. Add blacklist, greylist and blacklist data to the alarm list; The specific evaluation criteria are as follows: for S-band ground-based weather radar, the correlation coefficient threshold is 0.6, the standard deviation threshold is 4dB, and the average deviation threshold is [-5.5dB, 2.5dB]; for C-band and X-band ground-based weather radars, the correlation coefficient threshold is 0.5, the standard deviation threshold is 5dB, and the average deviation threshold is determined according to the probability distribution of a single band to ensure that 70% of the sites of a single-band ground-based radar are on the whitelist; The alarm analysis table is set up by integrating the results of the ground-based radar networking consistency verification algorithm based on space-borne radar and the results of the adjacent radar echo intensity consistency detection algorithm, combined with the maintenance and upgrade information of the ground-based weather radar.

6. The method for joint verification of satellite-borne and multi-band ground-based radar reflectivity factors as claimed in claim 1, characterized in that: The standard comparison of the ground-based radar reflectivity factor forms the matching result of the standard database and the new space-borne radar FY3-G / PMR, which specifically includes: Extracting the standard database of the ground-based radar reflectivity factor and matching it with the data of the space-borne radar FY3-G / PMR; Specifically, the standard database of ground-based radar reflectivity factors is a white list and a revised grey list; Add matching of bands corresponding to the reflectivity factors of S band, C band and X band, and use the matching results as the matching results of the standard database.

7. The method for joint verification of reflectivity factors of spaceborne and multi-band ground-based radars as claimed in claim 1, characterized in that: The setting of the evaluation classification forms and stores the evaluation results of the matching results of the standard database and the new spaceborne radar FY3-G / PMR under different categories, specifically including: Multiple groups are classified by station, province, radar type, month, altitude, precipitation intensity and frequency; The evaluation results corresponding to different stations, provinces, radar types, months, altitudes, precipitation intensity and frequency are displayed and stored according to the classification; The overall evaluation results of all spaceborne radars and ground-based radars are displayed and stored according to the evaluation indicators.

8. A joint verification system for satellite-borne and multi-band ground-based radar reflectivity factors, characterized in that: The system is used to implement the method according to any one of claims 1 to 7, and the system comprises: A data source determination module is used to set the data source of the spaceborne radar and the ground-based weather radar; A data quality control module, used to perform data quality control according to the data sources of the spaceborne radar and the ground-based weather radar to form a corrected data source; The matching and comparison module is used to match and compare the reflectivity factors of the space-borne radar GPM / DPR and the ground-based weather radar according to the corrected data source to form the optimal matching data; The consistency fusion module is used to establish a fused network radar consistency assessment algorithm to determine the alarm list and form a problem level; Standard comparison module, used to compare the reflectivity factor of ground-based radar and form the matching result between the standard database and the new space-borne radar FY3-G / PMR; The authenticity assessment module is used to set the assessment categories, form a standard database and store the assessment results of the new spaceborne radar FY3-G / PMR in different categories.

9. A computer-readable storage medium storing computer program instructions, characterized in that: The computer program instructions implement the method according to any one of claims 1 to 7 when executed by a processor.

10. An electronic device comprising a memory and a processor, characterized in that: The memory is used to store one or more computer program instructions, wherein the one or more computer program instructions are executed by the processor to implement the method according to any one of claims 1-7.

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