Abstract:
Three basic characteristics of seasonal and annual surface air temperature anomalies are analyzed by use of 160-station homogeneity adjustment scheme of China (Wang Panxing, et al, 2011) and conventional statistic methods.Anomalies in winter are the largest among the four seasons, occupying 47.7% of the total variance. Three north districts (namely Northwest China, North China and Northeast China) and the Tibetan Plateau are high variability regions in winter, with three north regions and the middle and lower reaches of Yangtze River for summer.The variance contribution of the linear warming of seasonal and annual anomaly is significant, and there are distinct differences between winter and summer. Significant annual and winter linear warming occurs in Northeast China, North China, northwest of Xinjiang and southwest of Tibetan Plateau. Weak linear cooling is observed for several stations of central and South China. The significant warming in summer is mainly located in the north of Northeast China, north of North China and Tibetan Plateau, but the range and strength are obviously less than those in winter. There is a large range cooling zone in the northwest and southeastern in summer.The variance contribution of interdecadal changes for annual, winter and summer anomalies is significant, and there are obvious differences between winter and summer. The significant interdecadal changes for annual surface air temperature in three north regions, most part of Tibetan Plateau, central China and part of East China are related to winter, while the southeast coastal areas is related to summer.Annual and seasonal mean surface air temperature calculated by network homogeneity adjustment in China is reasonable. The linear warming tendency for the national annual temperature is 1.4℃/58 a, with the maximum of 2.3℃/58 a for winter and the minimum of 0.6℃/58 a for the summer. The interdecadal changes of summer surface air temperature persists positive since the middle 1990s, while for winter and the whole year, stable warming has begun since the middle 1980s.