Abstract: Using of 25 national meteorological stations in the middle area of Shandong province, the temporal and spatial variation characteristics and correlation of air temperature and ground temperature in this area were analyzed by the methods of linear trend estimation, Mann-Kendall mutation analysis,T-sliding and ArcGIS spatial interpolation. The results showed that the interannual variations of air temperature and ground temperature in the middle area of Shandong province were similar and showed an undulating upward trend, and the lowest and highest temperature appeared in the same time. The climate tendency rate of air temperature was slightly higher than that of ground temperature. The seasonal variation of air temperature was all upward. The ground temperature showed a downward trend in summer, and the other seasons showed an upward trend. The warming trend of ground temperature in winter was significantly higher than that of air temperature, but the warming trend in other seasons was lower than air temperature. The air temperature changed before and after 1997, and the ground temperature occurred around 2012. The spatial distribution of temperature showed that the overall trend of air temperature was low in the southeast, high in the northwest, and the warming trend was fast in the east and slow in the west. The trend of ground temperature showed high in the west, low in the Changyi-Weifang-Changle-Wuyuan area, and the warming trend was fast in the north and slow in the south. There was an negative correlation between the air temperature and the longitude, and climate tendency rate of air temperature was positively correlated with the longitude. The level of ground temperature was negative related to longitude, and its climate tendency rate was also negative related to latitude. The months ground temperature and air temperature were extremely positively correlated. The correlation degree in the winter half year was higher than that in the summer half year. The month difference between ground temperature and air temperature was increasing month by month in the first half of the year, and decreasing month by month in the second half of the year.

Key words: air temperature, ground temperature, variation characteristics, correlation, the middle area of Shandong province