Abstract:

Based on the homogeneity test，according to the surface temperature data of 42 weather stations in Hena，Hubei and Hunan from 1961 to 2005，the time and space evolution characteristics of the surface temperature since 1961 were analyzed.The results show that the regional annual average temperature has a rising trend in the past 50 a，which increased 054℃ from 1961 to 2005，and the increase rate is 012℃/10 a.Except that the summer temperatures have a slight downward trend(the cooling rate is 0112℃/10 a)，the temperatures in winter，spring and autumn have rising trend in different degree，0286 ℃/10 a in winter，0188℃/10 a in spring，and 0131℃/10 a in autumn.The mostly rising period of annual average temperature and the average temperature in winter is since the mid80s of the last century，in spring is from 1990 to 2005，and in autumn is from 1970 to 2005.Though the summer average temperature shows a downward trend as a whole，it has a weak upward trend since 1985.The space distribution character of the annual average temperature rising is that the most obvious rising region is the central region，the second is the south and north and it is unobvious in the west，which has a downward trend.Overall，the most rising rate of the annual average temperature is in Hubei，which is 015 ℃/10 a，the second is in Henan，which is 0111℃/10 a；and the least is in Hunan，which is 0105℃/10 a.Cycle analysis shows that the regional annual average temperature has a 〖JP2〗significant cycle of about 4 yeas in the period between 1990 and 2000.Mutation test shows that the average annual temperature has a obvious mutation from the cold to warm around 1994.