1961—2018年陕西极端气温时空变化特征

基于陕西1961—2018年94个气象台站逐日气温资料,选取世界气象组织(WMO)提出的10种极端气温指数,分陕北、关中和陕南三个气候区,采用线性趋势分析、Mann-Kendall突变分析和Morlet小波分析,分析了陕西极端气温事件的时空变化特征.结果表明:陕西各极端气温指数在近60 a发生了显著变化,热指数的增加趋...

Spatial and temporal variation characteristics of extreme temperature in Shaanxi province from 1961 to 2018

Based on the daily temperature data of 94 meteorological stations in Shaanxi province from 1961 to 2018, ten types of extreme temperature indices proposed by WMO were employed to analyze the spatio-temporal characteristics of extreme temperature events in three climate regions of Shaanxi province i.e.Shanbei, Guanzhong, and Shannan using linear trend rate, Mann-Kendall and wavelet methods.The results show that the extreme temperature indices significantly change in the past 60 years in Shaanxi province.The increasing trend of the thermal index is more obvious than the decreasing trend of the cold index with a large inter-annual variation.The change of the night index is more prominent than that of the corresponding day index.Among them, the warm night days increase with a rate of 7.4 d per decade.Except for the extreme minimum temperature, the other cold indices change abruptly around 1995, while the abrupt changes for the numbers of warm night and warm day both occur after 2005.The change trends of ice days, cold days, and hot night days all indicate the most obvious zonal characteristics.The change trends of extreme minimum temperature, cold night days, warm night days, frost days, and summer days in Guanzhong are more significant than in the other two regions.The cyclical changes of the extreme index are mainly concentrated between 2 years and 8 years.Compared with the extreme index, the changes of the relative index and the absolute index are capable to better reflect the change trends in the annual average maximum and minimum temperatures in Shaanxi province.