Spatial and temporal variability characteristics of temperature in Huai River basin during 1961–2005 based on Kriging method

Surfaces of temperature at resolution of 1km×1km were generated by Kriging interpolation method, based on the series data from 170 observation stations in Huai River basin from 1961 to 2005. We used the grid data sets to analyze the spatial and temporal variability characteristics of temperature in Huai River basin. Results show that the higher temperature occur in the south and west of the basin, as compared with the lower in the north and east. There is a significantly warming trend in recent 45 years, especially for the northeast of the basin. The changes of temperature of various seasons have different patterns. The mean temperature of spring, autumn, winter and whole year increased significantly in the basin. The winter is characterized by the greatest warming trend, while the summer temperature has a weakly decrease trend. Mann-Kendall trend test indicated that the change of temperature in Huai River basin shifted from cooling to warming trend at 1994.