Effects of thermal discharge from big thermal power plant on environmental air temperature in Zouxian County of Shandong province

Based on air temperature data at Zoucheng and Yanzhou stations from 1960 to 2009, annual and seasonal variations of air temperature and its diurnal range were analyzed. According to the development of the thermal power plant in Zouxian County, the effects of thermal discharge from the thermal power plant on the environmental air temperature were discussed. The results indicate that the mean annual air temperature at Zoucheng and Yanzhou increases with 0.326 ℃∕10 a and 0.124 ℃∕10 a in the recent 50 a, respectively. The time of remarkable warming at Zoucheng is in accord with that putting into production of thermal power plant. During 1960 to 1994, the warming rates caused by thermal discharge are positive, and those of the minimum annual air temperature and the diurnal range are 0.51 ℃∕10 a and -0.35 ℃∕10 a, respectively. The contributions of many seasonal and annual air temperatures to warming reach 100%. During 1995 to 2005, the warming rates of air temperature caused by thermal discharge are also positive. The warming rates of mean annual air temperature is 0.209 ℃∕10 a, and those of the minimum and maximum mean annual air temperature are 0.118 ℃∕10 a and 0.056 ℃∕10 a, respectively. The diurnal range of annual air temperature is -0.100 ℃∕10 a. The effects of thermal discharge on mean air temperature and the minimum air temperature are significant, and not significant on the maximum air temperature. Although the contributions of many seasonal air temperatures to warming reduce, the effects of thermal discharge on the environmental air temperature are still significant.