By using the temperature and precipitation data from 11 counties in Dezhou，the aridityies of climate from 1981 to 2005 are calculated and compared with those from 1951 to 1980. The aridity increased from 1.45 to 1.64, and the city has become semiarid from semihumid climate. Meanwhile, the precipitation reduced by 19.64 mm per 10 years averagely in all counties. But the temperature is rising with an increase rate of 0.11 per 10 years averagely, and 0.3 degree per 10 years in winter. Significant warming is found in winter. The northern part has become frozen zone from subfrozen zone. Because of the climatic condition chan ge, the local environment and the corresponding types of the adjustment of local corrosive media standards are changed from Category 2 to Category 1, with corrosive media index adjustment coefficients being 0.9.