Analysis of temporal and spatial variation characteristics of summer surface air temperature in northwest China over the recent 46 years
To analyse the temporal and spatial change features of the summer air temperature in arid and semiarid area of northwest china as a whole, Using the summer mean surface air temperature data over the years of 1961 -2006 of 137 stations and the methods of linear regression analysis,multinomial fitting,EOF,REOF,Mann -Kendall、Glide T- examination ,Wavelet analysis and power spectrum analysis etc, we analyzed the characteristics of spatial distribution and temporal evolvement for temperature abnormality and the response of the averaged air temperature of summer to climate warming. The result shows that : 1 ) The mean air temperature of summer was 19.5℃ and the annual variation was small. 2)The summer temperature changed from reducing to increasing in mid - 1970s, the ascending tendency was more evident from 1994 and the abrupt change occurred in 1996. There were about 7 or 4 years periodic change for the summer temperature and the current cycle was still higher. 3) According to the EOF analyses, the summer temperature anomaly distribution was divided into three main modes: with the same temperature variation in all areas, with the different ones in the east and west or in the south and north. According to the REOF analyses, divided the area into six subregions further. 4)The rates of change of summer mean temperature reached 0.24℃/10a for the pass 46 years and warming trend more evident in the past 10 years. The temperature changing trend was increasing obviously in most of the area with the exception of parts area of Xinjiang, and synchronized response to global warming.
northwest Chinasummer temperaturetemporal and spatial variationclimatic warming
NETL
NSTL
万方数据
维普
