Establishment and Application of a Physical Inspection Method for the Artificial Precipitation Enhancement Effect

For a physical inspection of the artificial precipitation enhancement effect based on multi-source detection data, this study established the similarity measurement coefficient, APC (Analogy Deviation-Pearson Correlation Coefficient), of a contrast area selection and the dimensionless PIDI (Physical Inspection Dimensionless Index) index method for a physical inspection of the artificial precipitation enhancement effect. The results revealed the following: (1) The PIDI index method of a physical inspection for the artificial precipitation enhancement effect can minimize the variable influence of a seeding cloud body and precipitation with the similarity coefficient APC. In addition, a variety of dimensionless cloud physical detection parameters can be synthesized using a dimensionless method. Finally, the percentage change rate was used to measure the overall variations and the degree of various cloud physical parameters. (2) The PIDI index method was applied to inspect the precipitation enhancement effect of 24 aircraft from 2014 to 2019. The average change rate of seven indices (cloud top temperature, effective particle radius, optical thickness, liquid water path, combined reflectivity, ≥30 dBZ echo area, and vertical cumulative liquid water content) caused by artificial precipitation enhancement was 3.4%–19.6%. The change rate of hourly precipitation of 18 operations was 0–58.3%; the change rate of 6 operations was −37.5% to 0. The changes in the cloud physical parameters caused by most precipitation-increasing operations are smaller than the changes in precipitation. (3) For the 18 operations with a positive effect of precipitation enhancement, the cloud top temperature, combined reflectivity, and the vertical cumulative liquid water content for most operations were increased due to the artificial catalysis, effective particle radius, and optical thickness. Moreover, the liquid water path for most operations was decreased by artificial catalysis. (4) The PIDI index and K-value methods were compared using an aircraft precipitation enhancement operation. For the test of precipitation variation trend, the two methods were consistent. The main difference was that the PIDI index method could reflect the average change rate of all inspection indices caused by artificial catalysis.