Method for identifying artificial precipitation enhancement operation time and precipitation enhancement potential area of laminated hybrid cloud

Abstract

The invention relates to the technical field of artificial precipitation enhancement, and discloses a method for identifying the artificial precipitation enhancement operation time and the precipitation enhancement potential area of laminated mixed cloud, and the method comprises the steps: drawing a radar combination reflectivity parameter distribution diagram at each time through obtaining the weather radar base data of the one-time laminated mixed cloud precipitation process of a location; secondly, calculating a cumulus cloud development index of the rainfall process moment by moment by using a radar combined reflectivity parameter; according to the ratio of the adjacent cumulus cloud development indexes, judging the time for carrying out artificial precipitation enhancement operation in the laminated mixed cloud development time period; and finally, according to the radar combined reflectivity parameter suitable for the rainfall enhancement operation time, judging a rainfall enhancement potential area. According to the method, the single physical quantity of the combined reflectivity factor in the weather radar base data can be used for accurately calculating and reflecting the development or extinction stage of the laminated hybrid cloud system, and the artificial precipitation enhancement operation time and the precipitation enhancement potential area are identified, so that the scientificity and timeliness of the design and implementation of the artificial precipitation enhancement operation scheme are improved; and the scientificity and the accuracy of the airplane and ground precipitation enhancement operation are improved.

Description

Technical Field

[0001] The invention relates to the technical field of artificial rainfall enhancement, and in particular to a method for identifying an artificial rainfall enhancement operation time and rainfall enhancement potential area for stratocumulus mixed clouds. Background Art

[0002] Cumulus mixed clouds are very effective precipitation systems. The precipitation in the convective rain core area within the cloud is relatively large, and they are the focus of artificial weather modification operations. Many weather systems that affect the environment are often accompanied by obvious cumulus mixed cloud precipitation processes, such as the westerly trough, the northeast cold vortex, the North China cold vortex, the southwest vortex, etc. Cumulus mixed clouds are composed of layered clouds and cumuliform clouds embedded in them. The broad and moist stratus clouds provide rich and saturated water vapor conditions for cumulus clouds, and the spreading effect of cumulus clouds on stratus clouds can improve the precipitation efficiency of stratus clouds. Therefore, cumulus mixed clouds generally have a long life cycle and often bring large-scale continuous or intermittent precipitation.

[0003] Artificial weather modification refers to the activities of influencing the cloud physics process of the local atmosphere through artificial intervention under appropriate weather conditions in order to avoid or mitigate meteorological disasters, so as to achieve the purpose of increasing rain (snow), preventing hail, and eliminating clouds and fog. Nowadays, artificial weather modification is one of the important scientific and technological means to serve disaster prevention and reduction, protect people's production and life safety, improve people's quality of life, rationally develop and utilize climate resources, and build and protect the ecology.

[0004] The identification of the time and potential area for artificial rainfall enhancement in stratus mixed clouds has always been one of the difficulties in artificial rainfall enhancement. At present, due to the adverse factors such as the rapid changes in weather systems and limited detection equipment conditions in actual operations, commanders of weather modification operations have great difficulties in accurately judging the time and potential area for artificial rainfall enhancement, which affects the scientificity and effectiveness of the design and implementation of aircraft and ground operation plans. The existing technology lacks effective means to detect the distribution of supercooled water in advance, which makes it difficult to scientifically formulate aircraft operation plans. In view of the above problems, it is urgent for technical personnel in this field to propose a method for identifying the time and potential area for artificial rainfall enhancement in stratus mixed clouds that can accurately judge the time and potential area for artificial rainfall enhancement and improve the scientificity and accuracy of aircraft and ground rainfall enhancement operations. Summary of the invention

[0005] In view of the above technical problems, the present invention provides a method for identifying the artificial rainmaking operation time and rainmaking potential area of ​​stratocumulus mixed clouds, which solves the problems in the prior art that it is impossible to accurately determine the artificial rainmaking operation time and rainmaking potential area, and it is difficult to scientifically formulate aircraft and ground rainmaking operations.

[0006] In order to achieve the above object, the technical solution adopted in the present invention is as follows: A method for identifying artificial rainfall enhancement operation time and rainfall enhancement potential area of ​​stratocumulus mixed cloud of the present invention comprises the following steps: S1: Obtain weather radar basic data of a stratified mixed cloud precipitation process at the location, and draw a distribution map of radar combined reflectivity parameters at each time; S2: Calculate the cumulus development index of the precipitation process moment by moment using radar combined reflectivity parameters; If the grid point combined reflectivity is greater than or equal to 35 dBZ, it is considered to be cumulus; if the grid point combined reflectivity is greater than 15 dBZ and less than 35 dBZ, it is considered to be stratus. S3: Determine the appropriate time to carry out artificial rainfall enhancement operations during the development period of stratocumulus mixed clouds; S4: Determine the corresponding rainfall enhancement potential area based on the radar combination reflectivity parameters at the appropriate time for rainfall enhancement operations.

[0007] Furthermore, the weather radar base data in step S1 is a new generation of Doppler weather radar base data.

[0008] Furthermore, the cumulus development index in step S2 is the radar combined reflectivity at each moment, and the cumulus development index is calculated as follows: read the combined reflectivity data of the grid points within the radar observation range at the initial moment t, and record the total number of grid points with a combined reflectivity value greater than or equal to 15dBZ as A(t); record the total number of grid points with a combined reflectivity value greater than 15dBZ and less than 35dBZ as B(t); record the total number of grid points with a combined reflectivity value greater than or equal to 35dBZ as C(t); when B(t)>0 and C(t)>0, it indicates that there are stratified mixed clouds. When A(t)≥100, calculate the value of C(t) / A(t), which represents the proportion of cumulus grid points to all grid points of stratified mixed clouds, and is recorded as the cumulus development index D(t).

[0009] Furthermore, each moment is a complete body scan completed every 6 minutes.

[0010] Furthermore, the specific method for judging the suitable time for artificial rainfall enhancement operation in the development period of stratus mixed clouds in step S3 is as follows: reading the cumulus development index moment by moment, calculating D(t+1) / D(t), recorded as d(t+1); if d(t+1)>1, it indicates that the cumulus development index of the stratus mixed cloud system increases and the stratus mixed cloud system develops; if d(t+1)=1, it indicates that the cumulus development index remains unchanged and the stratus mixed cloud system is maintained stably; if d(t+1)<1, it indicates that the cumulus development index decreases, and the stratus mixed cloud system weakens until it gradually disappears; when the d values ​​of 5 consecutive moments are greater than 1, the stratus mixed cloud is in the initial development stage, and the moment D(t)≥2% is selected as the "suitable time for rainfall enhancement operation" until the d values ​​of 5 consecutive moments are less than 1 or D(t+n)≤2%, then the "suitable time for rainfall enhancement operation" ends.

[0011] Furthermore, the specific method for judging the corresponding rainfall enhancement potential area according to the radar combination reflectivity parameter of the suitable rainfall enhancement operation time in step S4 is as follows: the grid points with radar combination reflectivity>15dBZ and radar combination reflectivity<35dBZ at each moment within the suitable rainfall enhancement operation time are filled with green, and the grid points with radar combination reflectivity≥35dBZ are filled with red, indicating the rainfall enhancement potential area of ​​stratus mixed clouds at each moment.

[0012] Furthermore, the area filled with green is a relatively stable stratus cloud area, indicating a potential area for artificial rainfall enhancement by aircraft, ground anti-aircraft guns or rockets; the area filled with red is a cumulus cloud area, which has unstable convection, indicating a potential area for artificial rainfall enhancement by ground anti-aircraft guns or rockets.

[0013] Compared with the prior art, the present invention has the following beneficial effects: The present invention can accurately calculate the development or extinction stage of the stratified mixed cloud system by utilizing the single physical quantity of the combined reflectivity factor in the weather radar base data, and then identify the artificial rainmaking operation time and rainmaking potential area, thereby improving the scientificity, accuracy and timeliness of the rainmaking operation plan design. At the same time, it has universal significance in the artificial weather modification business and is easy to use. It further improves the scientificity and timeliness of the design and implementation of artificial rainmaking operation plans, which is conducive to improving the scientificity and accuracy of aircraft and ground rainmaking operations. It provides a reference and basis for the scientific and efficient development of artificial rainmaking business services. It fills the gap in the method of identifying the conditions for artificial rainmaking operations of stratified mixed clouds directly using weather radar base data, and improves the application value of weather radar base data in the artificial weather modification business. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Attached Figure 1 The radar combined reflectivity distribution map of Zhengzhou City at 14:02 on a certain day in this embodiment 2; Attached Figure 2 The radar combined reflectivity distribution map of Zhengzhou City at 16:01 on a certain day in this embodiment 2; Attached Figure 3 The radar combined reflectivity distribution map of Zhengzhou City at 18:01 on a certain day in this embodiment 2; Attached Figure 4 The radar combined reflectivity distribution map of Zhengzhou City at 21:03 on a certain day in this embodiment 2; Attached Figure 5 The evolution characteristics of the cumulus development index and the suitable rainfall enhancement operation time observed by radar in Zhengzhou City on a certain day from 13:05 to 23:02 in this embodiment 2; Attached Figure 6 The distribution map of rainfall-increasing potential areas in Zhengzhou City at 14:02 on a certain day in this embodiment 2; Attached Figure 7 The distribution map of rainfall-increasing potential areas in Zhengzhou City at 14:59 on a certain day in this embodiment 2; Attached Figure 8 The distribution map of rainfall-increasing potential areas in Zhengzhou City at 16:01 on a certain day in this embodiment 2; Attached Fig. 9 The distribution map of rainfall-increasing potential areas in Zhengzhou City at 16:58 on a certain day in this embodiment 2; Attached Fig.10 The distribution map of rainfall-increasing potential areas in Zhengzhou City at 18:01 on a certain day in this embodiment 2; Attached Fig.11 The distribution map of rainfall-increasing potential areas in Zhengzhou at 21:03 on a certain day in this embodiment 2; Attached Fig.12 The radar combined reflectivity distribution map of Zhengzhou City at 12:30 on a certain day in this embodiment 3; Attached Fig.13 The distribution map of rainfall-increasing potential areas in Zhengzhou at 12:30 on a certain day in this embodiment 3; Attached Fig.14 The radar combined reflectivity distribution diagram of Zhengzhou City at 10:00 on a certain day in this embodiment 4; Attached Fig.15 It is the distribution map of rainfall-increasing potential areas in Zhengzhou City at 10:00 on a certain day in this embodiment 4; Attached Fig.16 The radar combined reflectivity distribution map of Zhengzhou City at 23:01 on a certain day in this embodiment 5; Attached Fig.17 The distribution map of rainfall-increasing potential areas in Zhengzhou City at 23:01 on a certain day in this embodiment 5; Attached Fig.18 The radar combined reflectivity distribution map of Zhengzhou City at 13:02 on a certain day in this embodiment 6; Attached Fig.19 This is the distribution map of rainfall-increasing potential areas in Zhengzhou at 13:02 on a certain day in this embodiment 6. DETAILED DESCRIPTION

[0015] In order to make the purpose and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0016] Example 1

[0017] A method for identifying artificial rainfall enhancement operation time and rainfall enhancement potential area of ​​stratocumulus mixed cloud in this embodiment includes the following steps: S1: Obtain the basic data of the new generation Doppler weather radar for a stratified mixed cloud precipitation process at the location, and draw the distribution map of radar combination reflectivity parameters at each time; S2: Calculate the cumulus development index of the precipitation process at each moment using radar combined reflectivity parameters; the cumulus development index is the radar combined reflectivity at each moment (a complete volume scan completed every 6 minutes), where if the grid point combined reflectivity is greater than or equal to 35 dBZ, it is considered to be cumulus; if the grid point combined reflectivity is greater than 15 dBZ and less than 35 dBZ, it is considered to be stratus; The cumulus development index is calculated as follows: read the combined reflectivity data of the grid points within the radar observation range at the initial time t, and record the total number of grid points with a combined reflectivity value greater than or equal to 15dBZ as A(t); record the total number of grid points with a combined reflectivity value greater than 15dBZ and less than 35dBZ as B(t); record the total number of grid points with a combined reflectivity value greater than or equal to 35dBZ as C(t); when B(t)>0 and C(t)>0, it indicates the presence of stratus mixed clouds. When A(t)≥100, calculate the value of C(t) / A(t), which represents the proportion of cumulus grid points to all stratus mixed cloud grid points, and is recorded as the cumulus development index D(t).

[0018] S3: Determine the appropriate time for artificial rainfall enhancement during the development period of cumulonimbus mixed clouds: read the cumulonimbus development index at each moment, calculate D(t+1) / D(t), recorded as d(t+1), if d(t+1)>1, it means that the cumulonimbus development index of the cumulonimbus mixed cloud system increases, and the cumulonimbus mixed cloud system develops; if d(t+1)=1, it means that the cumulonimbus development index remains unchanged, and the cumulonimbus mixed cloud system is stable; if d(t+1)<1, it means that the cumulonimbus development index decreases, and the cumulonimbus mixed cloud system weakens until it gradually disappears; when the d values ​​of 5 consecutive moments are greater than 1, the cumulonimbus mixed cloud is in the initial development stage, and the moment from D(t)≥2% is selected as the "appropriate rainfall enhancement operation time", until the d values ​​of 5 consecutive moments are less than 1 or D(t+n)≤2%, then the "appropriate rainfall enhancement operation time" ends; S4: Determine the corresponding rainfall enhancement potential area according to the radar combination reflectivity parameters at the suitable rainfall enhancement operation time: fill the grid points with radar combination reflectivity>15dBZ and radar combination reflectivity<35dBZ at each moment in the suitable rainfall enhancement operation time with green, and fill the grid points with radar combination reflectivity≥35dBZ with red, which indicates the rainfall enhancement potential area of ​​cumulonimbus mixed clouds at each moment. Among them, the area filled with green is a relatively stable stratus cloud area, indicating the potential area for artificial rainfall enhancement by aircraft, ground anti-aircraft guns or rockets; the area filled with red is a cumulus cloud area with unstable convection, indicating the potential area for artificial rainfall enhancement by ground anti-aircraft guns or rockets.

[0019] Example 2

[0020] This example takes a large-scale stratified mixed cloud precipitation process in Zhengzhou, Henan Province as an example. Figure 1-11 Explain this in detail.

[0021] A method for identifying artificial rainfall enhancement operation time and rainfall enhancement potential area of ​​stratocumulus mixed cloud in this embodiment includes the following steps: S1: Obtain the new generation Doppler weather radar basic data of a stratified mixed cloud precipitation process from 13:05 to 23:02 on a certain day in Zhengzhou City, Henan Province, and draw the distribution map of radar combination reflectivity parameters at each time. See the attached Figure 1-4 ; S2: Cumulus mixed clouds are composed of stratus clouds and cumulus clouds embedded in them. It is generally believed that the radar echo reflectivity of stratus clouds is ≥15dBZ, and the radar echo reflectivity of cumulus clouds is ≥35dBZ. Based on this, the weather radar basic data of Zhengzhou City is analyzed, and the cumulus development index of the precipitation process is calculated at each moment using the radar combination reflectivity parameter; among them, the cumulus development index is the radar combination reflectivity at each moment (a complete volume scan completed every 6 minutes), among which, if the grid point combination reflectivity is greater than or equal to 35dBZ, it is considered to be cumulus clouds; if the grid point combination reflectivity is greater than 15dBZ and less than 35dBZ, it is considered to be stratus clouds; The calculation method of cumulus development index is as follows: read the combined reflectivity data of the grid points within the radar observation range at the initial time t, record the total number of grid points with combined reflectivity values ​​greater than or equal to 15dBZ as A(t); record the total number of grid points with combined reflectivity values ​​greater than 15dBZ and less than 35dBZ as B(t); record the total number of grid points with combined reflectivity values ​​greater than or equal to 35dBZ as C(t); when B(t)>0 and C(t)>0, it indicates the presence of stratus mixed clouds. When A(t)≥100, calculate the value of C(t) / A(t), which represents the proportion of cumulus grid points to all stratus mixed cloud grid points, recorded as cumulus development index D(t). Based on this calculation, the cumulus development index of the city at each time from 13:05 to 23:02 on a certain day and its evolution over time are obtained. See the attached Figure 5 .

[0022] S3: Determine the appropriate time for artificial rainfall enhancement during the development period of cumulonimbus mixed clouds: read the cumulonimbus development index at each moment, calculate D(t+1) / D(t), recorded as d(t+1), if d(t+1)>1, it means that the cumulonimbus development index of the cumulonimbus mixed cloud system increases, and the cumulonimbus mixed cloud system develops; if d(t+1)=1, it means that the cumulonimbus development index remains unchanged, and the cumulonimbus mixed cloud system is stable; if d(t+1)<1, it means that the cumulonimbus development index decreases, and the cumulonimbus mixed cloud system weakens until it gradually disappears; when the d values ​​of 5 consecutive moments are greater than 1, the cumulonimbus mixed cloud is in the initial development stage, and the moment from D(t)≥2% is selected as the "appropriate rainfall enhancement operation time", until the d values ​​of 5 consecutive moments are less than 1 or D(t+n)≤2%, then the "appropriate rainfall enhancement operation time" ends; The cumulus development index of the city at 13:05-23:02 on a certain day showed two peaks and one trough. Among them, 13:16-17:38 was the stage of increasing cumulus development index, and the stratocumulus mixed cloud system was in a continuous development stage, with a maximum peak of 8.78%; 17:38-20:34 was the stage of decreasing, and the stratocumulus mixed cloud system gradually weakened; 20:34-21:08 was the stage of increasing again, after which the stratocumulus mixed cloud system gradually weakened and disappeared. According to the method of this embodiment, 13:51-18:01 and 20:34-21:37 are the "suitable rain enhancement operation time" for the stratocumulus mixed cloud precipitation process in Zhengzhou City. See the attached Figure 5 , where the green-boxed time period is “suitable time for rainfall enhancement operations”.

[0023] S4: Determine the corresponding rainfall enhancement potential area according to the radar combination reflectivity parameters during the suitable rainfall enhancement operation time: fill the grid points with radar combination reflectivity >15dBZ and radar combination reflectivity <35dBZ at each moment during the suitable rainfall enhancement operation time with green, and fill the grid points with radar combination reflectivity ≥35dBZ with red, which indicates the rainfall enhancement potential area of ​​stratus mixed clouds at each moment.

[0024] According to this method, the potential area for rain enhancement operations can be obtained every 6 minutes from 13:51 to 18:01 and from 20:34 to 21:37 on a certain day in the city. Figure 6-11 The distribution maps of the potential rainfall enhancement areas at 14:02, 14:59, 16:01, 16:58, 18:01 and 21:03 are given. The green-filled areas are relatively stable stratus areas, indicating the potential areas for artificial rainfall enhancement by aircraft, ground anti-aircraft guns or rockets; the red-filled areas are cumulus areas with unstable convection, indicating the potential areas for artificial rainfall enhancement by ground anti-aircraft guns or rockets.

[0025] There are only two color scales on the distribution map of the rainfall potential area of ​​the method in this embodiment. Green represents stratus with an echo intensity of 15-35dBZ, and red represents cumulus with an echo intensity ≥35dBZ. At 16:01, there were 409478 stratiform cloud grid points in Zhengzhou, accounting for about 94.5%, and 23662 cumulus cloud grid points, accounting for about 5.5%. The commander of the rainfall enhancement operation can quickly determine whether it is suitable to carry out rainfall enhancement operations at this time, as well as the cumulus and stratus cloud areas suitable for rainfall enhancement operations, thereby improving the timeliness of rainfall enhancement operations.

[0026] Secondly, it is calculated that at 16:01 on a certain day, the total number of grid points of radar combination reflectivity and the total number of grid points of rainfall enhancement potential areas in Zhengzhou City are 628096 and 433140, respectively, indicating that the method of this embodiment can exclude at least 31% of the grid areas that are not suitable for rainfall enhancement operations, and only retain cumulus and stratus cloud areas accounting for about 69% as rainfall enhancement potential areas, which significantly improves the scientificity and accuracy of the design of rainfall enhancement operation plans.

[0027] Example 3

[0028] This example takes the mixed cloud precipitation process of a certain day in Zhengzhou City, Henan Province as an example. Figure 12-13 A detailed description is given of the artificial rainfall operation time at 12:30 on the same day and the identification of the rainfall enhancement potential area.

[0029] This embodiment provides a method for identifying the artificial rainfall enhancement operation time and rainfall enhancement potential area for stratocumulus mixed clouds, and the specific steps are the same as those in Embodiment 2.

[0030] By the attached Fig.12 It can be seen that the radar combined reflectivity distribution map uses 14 different color scales to display radar echoes of different intensities, which is not conducive to the rapid decision-making of the commander of the rainfall enhancement operation. Fig.13 It can be seen that there are only two color scales on the distribution map of rainfall potential areas in the attached figure. Green represents stratus with echo intensity of 15-35dBZ, and red represents cumulus with echo intensity ≥35dBZ. At 12:30 on a certain day in Zhengzhou, there were 20,916 cloud grid points, accounting for about 98.6%, and 292 cumulus grid points, accounting for about 1.4%. Rainfall operation commanders can quickly determine whether it is suitable to carry out rainfall operations at that time, as well as the cumulus and stratus cloud areas suitable for rainfall operations, which improves the timeliness of rainfall operations.

[0031] Secondly, it was calculated that the total number of grid points of the Zhengzhou radar combination reflectivity and the total number of grid points of the rainfall enhancement potential area at that moment were 134,791 and 21,208 respectively, indicating that the method of the present invention can exclude at least 84.3% of the grid areas that are not suitable for rainfall enhancement operations, and only retain 15.7% of the cumulus and stratus cloud areas as rainfall enhancement potential areas, which significantly improves the scientificity and accuracy of the design of rainfall enhancement operation plans.

[0032] Example 4

[0033] This example takes the mixed cloud precipitation process of a certain day in Zhengzhou City, Henan Province as an example. Figure 14-15 A detailed description is given of the artificial rainfall operation time at 10:00 on the same day and the identification of rainfall enhancement potential areas.

[0034] This embodiment provides a method for identifying the artificial rainfall enhancement operation time and rainfall enhancement potential area for stratocumulus mixed clouds, and the specific steps are the same as those in Embodiment 2.

[0035] By the attached Fig.14 It can be seen that the radar combined reflectivity distribution map uses 14 different color scales to display radar echoes of different intensities, which is not conducive to the rapid decision-making of the commander of the rainfall enhancement operation. Fig.15 It can be seen that there are only two color scales on the distribution map of rainfall potential areas in the attached figure. Green represents stratus with echo intensity of 15-35dBZ, and red represents cumulus with echo intensity ≥35dBZ. At 10:00 on a certain day in Zhengzhou, there were 311,245 cloud grid points, accounting for about 99.9%, and 69 cumulus grid points, accounting for about 0.01%. Rainfall operation commanders can quickly determine whether it is suitable to carry out rainfall operations at that time, as well as the cumulus and stratus cloud areas suitable for rainfall operations, which improves the timeliness of rainfall operations.

[0036] Secondly, it was calculated that the total number of grid points of the Zhengzhou radar combination reflectivity and the total number of grid points of the rainfall enhancement potential area at that moment were 621,331 and 311,314 respectively, indicating that the method of the present invention can exclude at least 49.9% of the grid areas that are not suitable for rainfall enhancement operations, and only retain 50.1% of the cumulus and stratus cloud areas as rainfall enhancement potential areas, which significantly improves the scientificity and accuracy of the design of rainfall enhancement operation plans.

[0037] Example 5

[0038] This example takes the mixed cloud precipitation process of a certain day in Zhengzhou City, Henan Province as an example. Figure 16-17 The artificial rainfall enhancement operation time at 23:01 on the same day and the identification of rainfall enhancement potential areas are explained in detail.

[0039] This embodiment provides a method for identifying the artificial rainfall enhancement operation time and rainfall enhancement potential area for stratocumulus mixed clouds, and the specific steps are the same as those in Embodiment 2.

[0040] By the attached Fig.16 It can be seen that the radar combined reflectivity distribution map uses 14 different color scales to display radar echoes of different intensities, which is not conducive to the rapid decision-making of the commander of the rainfall enhancement operation. Fig.17It can be seen that there are only two color scales on the rainfall potential area distribution map in the attached figure. Green represents stratus with echo intensity of 15-35dBZ, and red represents cumulus with echo intensity ≥35dBZ. At 23:01 on a certain day in Zhengzhou, there were 337,193 cloud grid points, accounting for about 87.1%, and 49,772 cumulus grid points, accounting for about 12.9%. The commander of the rainfall enhancement operation can quickly determine whether it is suitable to carry out rainfall enhancement operations at that time, as well as the cumulus and stratus cloud areas suitable for rainfall enhancement operations, which improves the timeliness of rainfall enhancement operations.

[0041] Secondly, it was calculated that the total number of grid points of the Zhengzhou radar combination reflectivity and the total number of grid points of the rainfall enhancement potential area at that moment were 599,311 and 386,965 respectively, indicating that the method of the present invention can exclude at least 35.4% of the grid areas that are not suitable for rainfall enhancement operations, and only retain 64.6% of the cumulus and stratus cloud areas as rainfall enhancement potential areas, which significantly improves the scientificity and accuracy of the design of rainfall enhancement operation plans.

[0042] Example 6

[0043] This example takes the mixed cloud precipitation process of a certain day in Zhengzhou City, Henan Province as an example. Figure 18-19 The artificial rainfall enhancement operation time at 13:02 on that day and the identification of rainfall enhancement potential areas were explained in detail.

[0044] This embodiment provides a method for identifying the artificial rainfall enhancement operation time and rainfall enhancement potential area for stratocumulus mixed clouds, and the specific steps are the same as those in Embodiment 2.

[0045] By the attached Fig.18 It can be seen that the radar combined reflectivity distribution map uses 14 different color scales to display radar echoes of different intensities, which is not conducive to the rapid decision-making of the commander of the rainfall enhancement operation. Fig.19 It can be seen that there are only two color scales on the rainfall potential area distribution map in the attached figure. Green represents stratus with echo intensity of 15-35dBZ, and red represents cumulus with echo intensity ≥35dBZ. At 13:02 on a certain day in Zhengzhou, there were 354,885 cloud grid points, accounting for about 97.8%, and 8,069 cumulus grid points, accounting for about 2.2%. Rainfall operation commanders can quickly determine whether it is suitable to carry out rainfall operations at that time, as well as the cumulus and stratus cloud areas suitable for rainfall operations, which improves the timeliness of rainfall operations.

[0046] Secondly, it was calculated that the total number of grid points of the Zhengzhou radar combination reflectivity and the total number of grid points of the rainfall enhancement potential area at that moment were 536643 and 362954 respectively, indicating that the method of the present invention can exclude at least 32.4% of the grid areas that are not suitable for rainfall enhancement operations, and only retain 67.6% of the cumulus and stratus cloud areas as rainfall enhancement potential areas, which significantly improves the scientificity and accuracy of the design of rainfall enhancement operation plans.

[0047] In summary, by comparing the radar combination reflectivity distribution map and the rainfall enhancement potential area distribution map obtained by the method of this embodiment, it can be seen that the rainfall enhancement potential area distribution map concisely and clearly gives whether there are cumulus and stratus mixed clouds suitable for rainfall enhancement operations at a certain moment, as well as cumulus cloud areas and stratus cloud areas suitable for rainfall enhancement operations.

[0048] It can be seen from this that the beneficial effects of this embodiment are as follows: This embodiment only needs to use a single physical quantity of the combined reflectivity factor in the weather radar base data to accurately calculate the development or extinction stage of the stratified mixed cloud system, and then identify the artificial rainmaking operation time and rainmaking potential area, which improves the scientificity, accuracy and timeliness of the rainmaking operation plan design. At the same time, it has universal significance in the artificial weather modification business and is easy to use. It can help the commanders of artificial weather modification operations to make judgments on the rainmaking operation time and potential area without referring to numerical weather forecast products and unable to obtain cloud microphysical quantity detection data, further improving the scientificity and timeliness of the design and implementation of artificial rainmaking operation plans, and providing reference and basis for the scientific and efficient development of artificial rainmaking business services. It fills the gap in the method of identifying conditions for artificial rainmaking operations for stratified mixed clouds directly using weather radar base data, and improves the application value of weather radar base data in artificial weather modification business.

[0049] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solutions formed by the specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for identifying the artificial rainfall enhancement operation time and rainfall enhancement potential area of ​​stratocumulus mixed clouds, characterized in that : It includes the following steps: S1: Obtain weather radar basic data of a stratified mixed cloud precipitation process at the location, and draw a distribution map of radar combined reflectivity parameters at each time; S2: Calculate the cumulus development index of the precipitation process moment by moment using radar combined reflectivity parameters; S3: Determine the appropriate time to carry out artificial rainfall enhancement operations during the development period of stratocumulus mixed clouds; S4: Determine the potential area for rainfall enhancement based on the radar combination reflectivity parameters at the appropriate time for rainfall enhancement operations.

2. The method for identifying the artificial rainfall enhancement operation time and rainfall enhancement potential area of ​​stratocumulus mixed clouds according to claim 1 is characterized in that : The weather radar base data in step S1 is a new generation of Doppler weather radar base data.

3. The method for identifying the artificial rainfall enhancement operation time and rainfall enhancement potential area of ​​stratocumulus mixed clouds according to claim 1, characterized in that : The cumulus development index in step S2 is the radar combined reflectivity at each moment, and the cumulus development index is calculated as follows: read the combined reflectivity data of the grid points within the radar observation range at the initial moment t, and record the total number of grid points with a combined reflectivity value greater than or equal to 15dBZ as A(t); record the total number of grid points with a combined reflectivity value greater than 15dBZ and less than 35dBZ as B(t); record the total number of grid points with a combined reflectivity value greater than or equal to 35dBZ as C(t); when B(t)>0 and C(t)>0, it indicates that there are stratus mixed clouds. When A(t)≥100, calculate the value of C(t) / A(t), which represents the proportion of cumulus grid points to all grid points of stratus mixed clouds, and is recorded as the cumulus development index D(t).

4. The method for identifying the artificial rainfall enhancement operation time and rainfall enhancement potential area of ​​stratocumulus mixed clouds according to claim 3 is characterized in that : Each moment described is a complete body scan completed every 6 minutes.

5. The method for identifying the artificial rainfall enhancement operation time and rainfall enhancement potential area of ​​stratocumulus mixed clouds according to claim 1, characterized in that : The specific method for judging the suitable time for artificial rainfall enhancement operation in the development period of stratocumulus mixed cloud in step S3 is as follows: read the cumulus development index moment by moment, calculate D(t+1) / D(t), recorded as d(t+1), if d(t+1)>1, it means that the cumulus development index of the stratocumulus mixed cloud system increases, and the stratocumulus mixed cloud system develops; if d(t+1)=1, it means that the cumulus development index remains unchanged, and the stratocumulus mixed cloud system is stably maintained; if d(t+1)<1, it means that the cumulus development index decreases, and the stratocumulus mixed cloud system weakens until it gradually disappears; when the d values ​​of 5 consecutive moments are all greater than 1, the stratocumulus mixed cloud is in the initial development stage, and the moment from D(t)≥2% is selected as the suitable rainfall enhancement operation time, until the d values ​​of 5 consecutive moments are all less than 1 or D(t+n)≤2%, then the "suitable rainfall enhancement operation time" ends.

6. The method for identifying the artificial rainfall enhancement operation time and rainfall enhancement potential area of ​​stratocumulus mixed clouds according to claim 1, characterized in that The specific method for judging the rainfall enhancement potential area according to the radar combination reflectivity parameter of the suitable rainfall enhancement operation time in step S4 is as follows: the grid points with radar combination reflectivity>15dBZ and radar combination reflectivity<35dBZ at each moment within the suitable rainfall enhancement operation time are filled with green, and the grid points with radar combination reflectivity≥35dBZ are filled with red, which indicates the rainfall enhancement potential area of ​​stratus mixed cloud at each moment.

7. The method for identifying the artificial rainfall enhancement operation time and rainfall enhancement potential area of ​​stratocumulus mixed clouds according to claim 6, characterized in that The areas filled with green are relatively stable stratus clouds, which are potential areas for artificial rainfall enhancement by aircraft, ground anti-aircraft guns or rockets; the areas filled with red are cumulus clouds, which have unstable convection and are potential areas for artificial rainfall enhancement by ground anti-aircraft guns or rockets.

Images