Spatial-temporal Variation of Air Temperature for the Recent 40 Years in Lhasa

• 作者: Yang LEI Hongbin WANG Baixue YU Wenxue FU Tongsuo LU Xinyu LIU Dong WEI
• 来源期刊: 气象与环境研究:英文版
• 学科: 交通运输
• 关键词: Global warming An abrupt change of temperature The correlation coefficient High altitudes The Tibetan Plateau Morlet wavelet analysis
• 年，卷（期）: 2021,（1）
• 页码范围: 6-12
• 页数: 7页
• 分类号: U46

摘要

It was all known that Lhasa went through a high temperature of 30.8℃in late June 2019,which hit record highs.To better understand the reasons,based on observations recorded at automatic weather stations in Lhasa,the characteristics of temperature variation at multiple time scales were studied using the linear trend method,Mann-Kendall mutation test,Morlet wavelet analysis,R/S analysis and so on.The results showed that:(a)the annual mean temperature(AMT)is rising at a rate of 0.5℃/10 a,and the average temperature for different seasons also increased significantly,especially in winter.(b)Although there was an intersection in 1995,it was found that AMT,did not pass the reliability test of significance levelα=0.05,this means there are no abrupt changes for AMT,the values are 7.97 and 9.15℃respectively before and after the intersection point.(c)AMT has a periodic oscillation for 18-25 and 25-32 a based on a mass of data and the wavelet variance diagrams in Lhasa.AMT has a main cycle of 28 a,cyclic patterns of temperature changes in spring,summer and autumn is similar to AMT,but it is relatively complex in winter.(d)The Hurst index of AMT and different seasons demonstrates that the temperature is likely to continue to rise in the future in Lhasa.