Statistical analysis of 2024 experimental acoustic rainfall enhancement, Jimsar County, Xinjiang

Acoustic rainfall enhancement (ARE) technology employs ground-based high-intensity sound sources to accelerating the coalescence of cloud droplets. This technology offers several operational advantages, including no airspace occupation, flexible operational control, and low operational costs, making it particularly suitable for long-term operations in arid and semi-arid regions. Furthermore, it enables integrated utilization of atmospheric and surface water resources through reservoir storage. From May to August 2024, field experiments were conducted in the Xidalongkou River Basin, Jimsar County, Changji Hui Autonomous Prefecture, Xinjiang Uygur Autonomous Region, China. An operational site was established and observational instruments were deployed to conduct comparative ARE experiments. Using ground-based precipitation observations from 13 valid operational days and 8 valid control days, an impact area identification algorithm was developed using the double-ratio method and Mann-Whitney U test to statistically analyze the spatial extent and effectiveness of ARE. The results are as follows: (1) The acoustic operations altered the localspatial distribution of rainfall, with enhanced rainfall observed at the sound-emissionsite and downwind areas, an impact area of 91 km2. (2) The rainfall enhancement ratio within the impact area was 58%, using Mann-Whitney U test; P-value=0.008. (3) Duringthe 13 operational days, enhanced rainfall depth of 68.4 mm and enhanced rainfall volume of 6.22×106 m³ were observed, the entire experimental period, a total rainfall volume of 8.21×106 m³ can be enhanced. This study provides empirical evidence and technical reference for implementing Xinjiang water augmentation strategy. However, operational application of this technology requires further validation at larger spatiotemporal scales and in-depth investigation of cloud microphysical processes.