| Global warming of the climate system on the earth has been concerned widely in recent a hundred years. Qinghai-Xizang Plateau is the highest plateau with the most complex topography in the world. Special geography station and topography make the plateau form unique atmosphere circulation and climate. Not only the climate of China but also the climate of Aria-Europe continent and even that of the world are affected greatly by the existence of the plateau. At the same time, the plateau is more sensitive to greenhouse gases than the other regions and has close relationship with the global environment changes. The study on the temporal and spatial characters of air temperature variation on Qinghai-Xizang plateau in 1961~2002 years has great sense for the understanding of its climate background, the relationship with the climate variation of east of China and global climate variation as well as physical environment changes on the plateau.The temporal and spatial characters of temperature variation on Qinghai-Xizang plateau in recent 42 years are analyzed by modern meteorology statistical methods in the paper. Comparisonswith the climate changes in east of China to analyze their correlations and differences of temporal phrase are also made. The reasons are also discussed. The following are the main contents of the paper:1.Average temperature distribution during the years of 1961-1990 on Qinghai-Xizang Plateau, the average annual, winter and summer air temperature of 74 stations for the 30 years are calculated. The characters of temperature contribution are analyzed according to the graphs of equal lines of temperature. They show no great difference: all relative colder regions are the south of Qinghai province and the west of Mount Qilian. The relative warmer regions are Yarlung Zangbo River valley and Sanjiang valleys, the northwest fringe of the plateau, Chaidamu Basin and valleys of Huanghe and Huangshui.2.The spatial character of air temperature variation on the plateau: The 74X42 temperature matrixes of the annual, winter and summer are EOF decomposed by the method of Principle Components Analysis. According to the results, it is held that the temperature variation mainly presents entire identity. The opposite variation trend of the north and the south plateau is the main spatial character and the differences between the east and the west is subsidiary. According to the results three subregions are categorized. The northern subregion includes the south of Xinjiang, Qinghai and some areas of the south of Gansu. The southern subregion includes Xizang, the west of Sichuan and some areas of Yunnan. The western subregion is the west of Xizang. According to the loading values and topography characters, six representative stations are selected: Hetian, Wuqiaoling, Wudaoliang, Shiquanhe, Lasa and Changdu.3.Temporal characters of the air temperature variation on the plateau, the temperature variation tendence, cold and warm phrases and periods of the representative stations are analyzed. It is concluded that the air temperature of entire plateau is rising from the temperature variation tendencies of the 6 stations. The spatial distributions of temperature rise of the annual, winter and summer are further analyzed by linear fitting for the 74 stations. Different categories are divided for the representative stations according to the polynomial fitting curves of the temperature series. Air temperature variation periods are attained by Functional Spectral Analysis. In addition, the unsymmetry of the lowest and the highest temperature variations is also analyzed.4.Analysis of air temperature anomaly and abrupt changes. Abnormal cold and warm years are separated out by the relationship between the cumulative averaged air temperature and the standard deviation. To examine whether the turning points of the cumulative anomalous curve ofaveraged air temperature are abrupt changes, Signal Noise Ration is used. If S/N are bigger than 1, the year of the turning point is thought having taken place abrupt change, otherwi...
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