Response of runoff and its components to climate change in the Manas River of the Tian Shan Mountains  

作　　者：Ze-Long YANG Peng BAI 

机构地区：[1]Key Laboratory of Water Cycle and Related Land Surface Processes,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 10010l,China [2]University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Advances in Climate Change Research》2024年第1期62-74,共13页气候变化研究进展（英文版）

基　　金：supported by the Third Xinjiang Scientific Expedition Program (2021xjkk0806);the National Natural Science Foundation of China (42271033,51979263).

摘　　要：A warming-wetting climate trend has led to increased runoff in most watersheds in the Tian Shan Mountains over the past few decades.However,it remains unclear how runoff components,that is,rainfall runoff(Rrain),snowmelt runoff(Rsnow),and glacier meltwater(Rglacier),responded to historical climate change and how they will evolve under future climate change scenarios.Here,we used a modified Hydrologiska Byrans Vattenbalansavdelning(HBV)model and a detrending method to quantify the impact of precipitation and temperature changes on runoff components in the largest river(Manas River)on the northern slope of the Tian Shan Mountains from 1982 to 2015.A multivariate calibration strategy,including snow cover,glacier area,and runoff was implemented to constrain model parameters associated with runoff components.The downscaled outputs of 12 general circulation models(GCMs)from the Sixth Coupled Model Intercomparison Project(CMIP6)were also used to force the modified HBV model to project the response of runoff and its components to future(2016-2100)climate change under three common socio-economic pathways(SSP126,SSP245,and SSP585).The results indicate that Rrain dominates mean annual runoff with a proportion of 42%,followed by Rsnow(37%)and Rglacier(21%).In terms of inter-annual variation,Rrain and Rsnow show increasing trends(0.93(p<0.05)and 0.31(p>0.05)mm per year),while Rglacier exhibits an insignificant(p>0.05)decreasing trend(-0.12 mm per year),leading to an increasing trend in total runoff(1.12 mm per year,p>0.05).The attribution analysis indicates that changes in precipitation and temperature contribute 8.16 and 10.37 mm,respectively,to the increase in runoff at the mean annual scale.Climate wetting(increased precipitation)increases Rrain(5.03 mm)and Rsnow(3.19 mm)but has a limited effect on Rglacier(-0.06 mm),while warming increases Rrain(10.69 mm)and Rglacier(5.79 mm)but decreases Rsnow(-6.12 mm).The negative effect of glacier shrinkage on Rglacier has outweighed the positive effect of warming on Rglaciers resulti

关 键 词：Tian Shan Rainfall runoff Snowmelt runoff Glacier meltwater Warming-wetting Tipping point 

分 类 号：P46[天文地球—大气科学及气象学]