高原气象2026,Vol.45Issue(3):654-665,12.DOI:10.7522/j.issn.1000-0534.2025.00123
降雨事件特征对季节性冻土水热状态的影响
The Influence of Rainfall Characteristics on Seasonal Frozen Soil Hydrothermal Changes
摘要
Abstract
Under the ongoing warming and humidification trend on the Qinghai-Xizang Plateau,the influence of rainfall on the hydrothermal conditions of frozen soil has become increasingly significant.To investigate the ef-fects of rainfall characteristics on the hydrothermal state of seasonally frozen soil,this study analyzed the respons-es of frozen soil hydrothermal conditions under varying rainfall regimes based on continuous in-situ monitoring of meteorological variables and soil hydrothermal dynamics in Riwoqê County.The results indicate that the study ar-ea is dominated by short-duration(0 h<H≤6 h)and small-amount(0.1 mm≤P≤9.9 mm)events,accounting for 57.81%and 84.39%of the total,respectively.Under similar rainfall amounts(7.6 mm≤P≤8.1 mm),short-du-ration events during the thawing period accelerates cooling of the 0~15 cm soil layer(by 11.13%~81.49%)and reduces heating of the 25~35 cm layer(by 18.18%~85.07%),while longer events primarily mitigate tempera-ture changes.Short-duration rainfall also produces the largest increase in soil moisture(average 6.90%at 5~35 cm),though the rates of increase and decrease generally decline with rainfall duration.Under comparable du-rations(10 h≤H≤13 h),heavy rainfall induces rapid cooling in the 0~25 cm soil layer and slight warming at 35~45 cm(1.0℃and 0.8℃,respectively),whereas lighter rainfall mainly weakens temperature variation.Small,short-duration events(H≤5 h,P≤5 mm)slowed temperature change with minimal effects below 15 cm,and soil moisture exhibits greatest increases during the complete thawing period(0.59%at 2.5~15 cm)while smallest during complete freezing period.Overall,rainfall typically had a cooling effect,as theoretical rainwater temperatures were consistently lower than surface soil temperatures(hourly temperature difference was-1.57~30.99℃,daily average temperature difference was 0.45~15.86℃),particularly from June to August.关键词
青藏高原/降雨特征/水热变化/冻融过程/季节性冻土Key words
Qinghai-Xizang Plateau/rainfall characteristics/hydrothermal changes/freeze thaw process/sea-sonal frozen soil分类
天文与地球科学引用本文复制引用
舒敏,余钟波,江鹏,白玛旺堆,顿珠加措,吴仁达,鞠琴..降雨事件特征对季节性冻土水热状态的影响[J].高原气象,2026,45(3):654-665,12.基金项目
西藏自治区科技计划项目(XZ202402ZY0009,XZ202401JD0024) (XZ202402ZY0009,XZ202401JD0024)
国家自然科学基金项目(U2240217,U2340213) (U2240217,U2340213)
水灾害防御全国重点实验室自主研究项目(5240152N2) (5240152N2)