Intensified warming suppressed the snowmelt in the Tibetan Plateau  

作　　者：Xiang LI Peng CUI Xue-Qin ZHANG Fang ZHANG 

机构地区：[1]Key Lab of Land Surface Pattern and Simulation,Institute of Geographic Sciences and Natural Resources Research,Beijing 100101,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]China‒Pakistan Joint Research Center on Earth Sciences,Chinese Academy of Sciences and Higher Education Commission,Islamabad 45320,Pakistan

出　　处：《Advances in Climate Change Research》2024年第3期452-463,共12页气候变化研究进展（英文版）

基　　金：the Second Tibetan Plateau Scientific Expeditionand Research Program(STEP)(2019QZKK0903);the Special Project for the Construction of Nyingchi National Sustainable Development Pilot Zone(2023-SYQ-006);the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA23090302).

摘　　要：Understanding how hydrological factors interrelate is crucial when examining the impact of climate warming on snowmelt.However,these connections are often overlooked,leading to an unclear relationship between temperature and snowmelt.This study investigates the complex interplay between temperature and snowmelt in the Tibetan Plateau from 1961 to 2020,focusing on how extreme high-temperature events affect the frequency of extreme snowmelt.Using a structural equation model,we detected three temperature-related factors that predominantly influenced snowmelt and extreme snowmelt.The annual average temperature was found to have a significant indirect impact on snowmelt,mediated by changes in snowfall,snow depth and snow cover.By contrast,high-temperature days(daily maximum temperatures exceeding the 90th percentile)and heat waves(at least three consecutive high-temperature days)negatively affected extreme snowmelt directly or indirectly.The direct effect of increasing extreme temperature events was associated with an earlier onset of high-temperature periods,which accelerated snowmelt and shortened the duration of extreme snowmelt periods.Additionally,the reduction in snow cover owing to warming emerged as a main factor suppressing snowmelt and extreme snowmelt frequencies.We also revealed spatiotemporal variations in the temperature‒snowmelt relationship that highly depended on changes in snowmelt patterns.The study elucidated why warming suppresses snowmelt and extreme snowmelt events in the Tibetan Plateau,highlighting the mediating roles of snow-related and phenological factors.The findings will provide scientific support for climate simulation and water management policymaking in alpine regions worldwide.

关 键 词：Climate change Extreme temperature SNOWMELT Structural equation model Tibetan Plateau 

分 类 号：P33[天文地球—水文科学]