Spatiotemporal Variability in Extreme Temperature Events in an Arid-Semiarid Region of China and Their Teleconnections with Large-Scale Atmospheric Circulation  

作　　者：Lin Zhang Yanfeng Liu Menggui Jin Xing Liang 

机构地区：[1]State Key Laboratory of Biogeology and Environmental Geology,China University of Geosciences,Wuhan 430078,China [2]School of Environmental Studies,China University of Geosciences,Wuhan 430078,China

出　　处：《Journal of Earth Science》2023年第4期1201-1217,共17页地球科学学刊（英文版）

基　　金：supported by the National Natural Science Foundation of China (No.41672246);the Fundamental Research Funds for the Central Universities,China University of Geosciences (Wuhan)(No.1910491T05)。

摘　　要：With a warming climate,temperature extremes have been a main global issue in recent decades due to their potential influence on the sustainable development of human life and natural ecosystems.In this study,12 indicators of extreme temperature events are used to evaluate the spatiotemporal distribution,periodic structure and teleconnections with large-scale atmospheric circulation in Xinjiang,Northwest China by combining wavelet coherence(WTC) analysis based on continuous wavelet transform(CWT) analysis with the sequential Mann-Kendall test.We find that over the past six decades,the climate in Xinjiang has become warmer and has suffered from increases in the frequency of warm extremes and decreases in the frequency of cold extremes.Warm extremes have mainly occurred in the southern Tianshan Mountains surrounding the Tarim Basin and western part of the Taklamakan Desert,and cold extremes have primarily occurred in the southwestern Altai Mountains and northern foot of the Tianshan Mountains.Extreme temperature events,including warm extremes,cold extremes,and other temperature indices,have significant interannual variability,with the main oscillation periods at smaller(2–4-year band),intermediate(4–7-year band),and greater time scales in recent decades.Furthermore,cold-extreme indices,including frost days,cool days,and cool nights all show a clear changepoint during 1990–1997 at the 95% confidence level,and both ice days and cold spell duration indicator have a potential changepoint during 1981–1986.However,the changing points for warmextreme indices are detected during 1992–1998.The temperature variables are significantly correlated with the EI Ni?o-Southern Oscillation(ENSO) and Arctic Oscillation(AO),but less well correlated with the Pacific Decadal Oscillation(PDO).The phase difference in the WTC spectra is not uniform between temperature extremes and climatic oscillations.Our findings will have important implications for local governments in taking effective measures to mitigate the potential effects

关 键 词：extreme temperature events spatiotemporal variability large-scale atmospheric circu-lation inland arid-semiarid region wavelet analysis climate change. 

分 类 号：P426.616[天文地球—大气科学及气象学] P434