Synchronism of runoff response to climate change in Kaidu River Basin in Xinjiang,Northwest China

The runoff in alpine river basins where the runoff is formed in nearby mountainous areas is mainly affected by temperature and precipitation.Based on observed annual mean temperature,annual precipitation,and runoff time-series datasets during 1958–2012 within the Kaidu River Basin,the synchronism of runoff response to climate change was analyzed and identified by applying several classic methods,including standardization methods,Kendall’s W test,the sequential version of the Mann-Kendall test,wavelet power spectrum analysis,and the rescaled range(R/S) approach.The concordance of the nonlinear trend variations of the annual mean temperature,annual precipitation,and runoff was tested significantly at the 0.05 level by Kendall’s W method.The sequential version of the Mann-Kendall test revealed that abrupt changes in annual runoff were synchronous with those of annual mean temperature.The periodic characteristics of annual runoff were mainly consistent with annual precipitation,having synchronous 3-year significant periods and the same 6-year,10-year,and 38-year quasi-periodicities.While the periodic characteristics of annual runoff in the Kaidu River Basin tracked well with those of annual precipitation,the abrupt changes in annual runoff were synchronous with the annual mean temperature,which directly drives glacier-and snow-melt processes.R/S analysis indicated that the annual mean temperature,annual precipitation,and runoff will continue to increase and remain synchronously persistent in the future.This work can improve the understanding of runoff response to regional climate change to provide a viable reference in the management of water resources in the Kaidu River Basin,a regional sustainable socio-economic development.