Key Factors Influencing Drift Success Rate of New-type Meteorological Balloons

Beidou Sounding System utilizes innovative dual-layer latex balloons to conduct drift observations, a crucial capability for high-altitude atmospheric research. The dual-layer latex balloon, consisting of two nested latex meteorological balloons, facilitates stable and extended observations at target altitudes, a process known as drift. Drift is defined as the phenomenon in which a balloon maintains a near-horizontal movement within an expected altitude range of 26-30 km for an extended duration of at least 4 hours. To improve the success rate of drift procedures, this study examines the influence of various factors related to both inner and outer balloons on overall success rate. The research is based on comprehensive drift sounding observation data collected from Guangdong. By analyzing these factors, the study aims to determine an optimal inflation range for balloons to maximize their drift success rate. Results indicate that the theoretical volume of inflation required for the inner balloon to maintain stable drift at the target altitude is 55.6 mol. However, the inflation volume must be adjusted based on the time of day. During daytime, the inflation volume of the inner balloon should be maintained at 52.6±2 mol, while at night, it should be increased to 57.6±2 mol. The study also emphasizes the substantial influence of the outer balloon’s burst altitude on the success rate. When the outer balloon bursts within the expected altitude range of 26-30 km, the drift success rate can reach 82%, representing a significant improvement compared to other altitude intervals. The total inflation volume, daytime and nighttime conditions, and prevailing weather patterns are identified as key factors influencing the burst altitude of the outer balloon and, consequently, the success rate of its drift. Further analysis demonstrates that the success rate of drift varies under different environmental conditions. Daytime observations yield higher success rates than nighttime observations, and clear sky conditions are more favorable than cloudy or rainy weather. Specifically, the success rate under rainy conditions drops significantly to just 50.2%. Through an integrated analysis of theoretical calculations and empirical measurement data, an optimized inflation control protocol is established for dual-balloon systems. In October 2024, this range is tested and validated at 4 sounding stations located in Guangdong. Validation results are highly promising, demonstrating that the optimized inflation range could help achieve a drift success rate up to 93.5%. This research provides systematic theoretical support and methodological guidance for the application of dual-mode meteorological balloons.