Page 113 - 《高原气象》2026年第1期

1 期 何佩鸿等：雅鲁藏布大峡谷冬/夏季风期水汽输送特征及其与江河源区降水的关系研究 109

Characteristics of Water Vapor Transport during the Winter/Summer

Monsoon Periods in the Yarlung Zangbo Grand Canyon Region
and Its Relationship with Precipitation in
the Three-River Source Region

HE Peihong， LAI Xin， LI Boyuan， ZHANG Ge
（School of Atmospheric Sciences， Plateau Atmosphere and Environment Key Laboratory of Sichuan Province， Chengdu Plain Urban
Meteorology and Environment Observation and Research Station of Sichuan Provincem Sichuan Meteorological Disaster Prediction
and Early Warning Engineering Laboratoy， Chengdu University of Information Technology， Chengdu 610225， Sichuan， China）

Abstract： The Yarlung Zangbo Grand Canyon region （YZGC） is an important water vapor transport channel on
the Qinghai-Xizang Plateau， and the water vapor transport of the YZGC has an important impact on the weather
and climate of the plateau. Based on the ERA5 reanalysis data and CN05. 1 precipitation data from 1986-2021，
this paper analyzes the water vapor transport characteristics of the YZGC during the summer monsoon and winter
monsoon periods and studies its relationship with precipitation in Three-River Source Region （TRSR） during the
plateau summer monsoon period. The results showed that： （1） The precipitation in the YZGC was more in the
southeast and less in the northwest and showed an increasing trend in time， and the increase in the summer mon‐
soon period was greater than that of the annual average and the winter monsoon period. The water vapor flux of
the YZGC mainly comes from the southwest water vapor transport from the Indian Ocean to the Bay of Bengal，
followed by the westerly water vapor transport from the southern branch of the mid-latitudes.（2） The south and
west boundaries of the YZGC are the water vapor input boundaries throughout the year， and the east and north
boundaries are the water vapor output boundaries， and the water vapor transport flux during the summer mon‐
soon is stronger than that during the winter monsoon period. The YZGC is a positive area of net water vapor
flux， and the net water vapor income shows a significant decreasing trend.（3） The low-level 1000~600 hPa orig‐
inates from the Indian Ocean to the Bay of Bengal and the western Pacific Ocean， and the water vapor transport
enters the plateau from the southern boundary of the YZGC， and the southern boundary is the main boundary of
water vapor input. The upper layer is 600~300 hPa， and the middle and high latitudes are significant westerly wa‐
ter vapor transport， and the water vapor is mainly imported from the western boundary and exported from the
eastern boundary.（4） There is a significant positive correlation between the water vapor flux of the YZGC and
the precipitation in the central and eastern parts of the TRSR during the summer monsoon. Anomalous southeast
water vapor transport from the Bay of Bengal， as well as anomalous southwest water vapor transport from the
northern Bay of Bengal and the southwestern side of the plateau， enters through the western and southern bound‐
aries of the YZGC， providing ample moisture to the central and eastern parts of the TRSR. The upward motion of
this water vapor in the central and eastern TRSR leads to increased precipitation.
Key words： The Yarlung Zangbo Grand Canyon region； water vapor transport； the Three-River Source Region；
precipitation； plateau monsoon