Monitoring Soil Water Content and Measurement Depth of Cosmic-Ray Neutron Sensing in the Tibetan Plateau

作者：Xin Wang, Rong Liu, Markus Köhli, Jonas Marach, Zuoliang Wang · 发表于：Journal of Hydrometeorology · 年份：2025 · DOI：10.1175/jhm-d-23-0103.1 · 被引用次数：10 · 研究领域：Nuclear Physics and Applications

Abstract This work aims at evaluating the potential application of two cosmic-ray neutron sensing (CRNS) soil water content (SWC) retrieval methods and discusses the effective measurement depth of CRNS retrieval and vertical weights of different layers in a semihumid alpine meadow on the Tibetan Plateau. In this study, the widely used N0 method and the latest published method derived from physical principles named the universal transport solution (UTS) were used for SWC estimation during the whole nonfrozen season on the Tibetan Plateau. The N0 and UTS methods successfully retrieved the SWC on the Tibetan Plateau, and their variations were generally consistent. The effective measurement depths calculated by the N0 and UTS methods showed similar fluctuation patterns, ranging from 9.7 to 14.5 cm and 17.8 to 20 cm, with mean values of 12.0 and 19.2 cm, respectively. This work verified that the weighting methods of the N0 and UTS models provided credible performance for the effective measurement depths. The N0 method provided measurement depths more close to the surface, and the UTS method yielded slightly deeper averages. The UTS equation had a more sensitive response to periods of low precipitation. Including detailed Ultra Rapid Neutron-Only Simulation (URANOS) Monte Carlo simulations of the full time series, we find specifically an excellent agreement in the summer period. Our analysis suggests that CRNS is a promising innovation for SWC measurement and can be extended in its...