Air temperature variation of Weihe river basin in recent 60 years and its regional differences

Based on the atmospheric temperature data of 45 stations in and around Wei River basin during 1951~2009,spatial interpolation,linear regressive analysis and climatic mutation analysis were applied to analyze the climate trend and so on.Results showed that:(1) The annual mean temperature and the minimum temperature of the basin showed a increasing trend,rising at the rates of 0.252℃/10a and 0.261℃/10a respectively.The proportion of the area where the average annual temperature was more than 9 increased by 34.78% and where the average annual temperature was more than 9 increased by 34.78% from 1951 to 2009.(2) Apart from the 1980s,the average annual maximum temperatures have been in an ascending trend,rising at the rates of 0.255℃/10a.The proportion of the area where the average annual maximum temperatures were more than 16℃ decreased from 46.27% in 1950s to 37.15% in 1980s,then increased to 81.63% after 2000.(3) The turning points among the average annual temperature,the average minimum temperature and the average annual maximum temperature located around 1990.(4) Average diurnal range in temperature had a decreasing trend from 1950s to 1970s and the warming trends started in the 1980s.The proportion of the area where average diurnal range in temperature was more than 11℃ decreased from 55.96% in 1950s to 41.58% in 1980s,then increased to 61.07% after 2000.