Tang et al. (2026) Spatiotemporal changes of Indian monsoon-influenced precipitation over the world's highest large river: The Yarlung Zangbo River basin from a meridional wind perspective

Identification

• Journal: The Science of The Total Environment
• Year: 2026
• Date: 2026-01-09
• Authors: Xinyao Tang, Ji Chen, J. Z. Li, Yi Lu
• DOI: 10.1016/j.scitotenv.2026.181347

Research Groups

• Department of Civil Engineering, The University of Hong Kong, Hong Kong
• School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, China
• Department of Construction and Quality Management, School of Science and Technology, Hong Kong Metropolitan University, Hong Kong

Short Summary

This study investigates the mechanisms linking Indian Summer Monsoon variability, meridional winds, and spatiotemporal precipitation changes in the Yarlung Zangbo River Basin (YRB) from 1979 to 2019, revealing that a weakening monsoon reduces downstream precipitation while increasing it midstream and upstream, primarily driven by meridional wind variations.

Objective

• To systematically analyze precipitation changes and quantify the role of meridional wind variability in modulating June to September (JJAS) precipitation across the Yarlung Zangbo River Basin (YRB) from 1979 to 2019, addressing the unclear mechanisms linking Indian Summer Monsoon (ISM) variability, meridional winds, and regional precipitation trends.

Study Configuration

• Spatial Scale: Yarlung Zangbo River Basin (YRB) on the Tibetan Plateau.
• Temporal Scale: 1979 to 2019 (40 years), focusing on the June to September (JJAS) period.

Methodology and Data

• Models used: Weather Research and Forecasting (WRF) model.
• Data sources: Multiple data sources, including observations and reanalysis.

Main Results

• The downstream YRB experienced significant declines in meridional wind and precipitation, while moderate increases occurred upstream and midstream.
• Net water vapor input accounts for approximately 83 % of precipitation in the downstream, 41 % in the midstream, and 55 % in the upstream YRB.
• Numerical sensitivity tests using the WRF model showed that a 10 % reduction in meridional wind leads to a 4.9 % decrease in downstream precipitation.
• Downstream precipitation is primarily dominated by variations in Indian Monsoon-driven meridional winds.

Contributions

• Systematically analyzes precipitation changes and quantifies the role of meridional wind variability in modulating JJAS precipitation across the YRB.
• Clarifies the mechanisms linking Indian Summer Monsoon variability, meridional winds, and regional precipitation trends in the YRB.
• Provides numerical sensitivity test results demonstrating the impact of meridional wind reduction on downstream precipitation.

Funding

• [No funding information provided in the paper text.]

Citation

@article{Tang2026Spatiotemporal,
  author = {Tang, Xinyao and Chen, Ji and Li, J. Z. and Lu, Yi},
  title = {Spatiotemporal changes of Indian monsoon-influenced precipitation over the world's highest large river: The Yarlung Zangbo River basin from a meridional wind perspective},
  journal = {The Science of The Total Environment},
  year = {2026},
  doi = {10.1016/j.scitotenv.2026.181347},
  url = {https://doi.org/10.1016/j.scitotenv.2026.181347}
}