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With the pan evaporation data, temperature, sunlight, precipitation, and some other meteorological data from 1971 to 2010 in Yantai, the changes in pan evaporation characteristics are analyzed. By using the linear regression, correlation analysis, wavelet analysis, and stepwise regression analysis methods, effects of meteorological factors on the changes of evaporation are analyzed. The results show that there existed periodic variation in annual evaporation with the main periods of 2 to 3 years and the periods of 4 to 8 and 8 to 12 years; there were periodic changes of 3 to 5, 5 to 7, 7 to 11, and 2 to 4 years, respectively, in evaporation in spring, summer, autumn, and winter. Increased average relative humidity and reduced sunshine duration brought about the reduction in annual evaporation, and factors influencing the changes of evaporation in different seasons were different. Sunshine duration and total cloud cover were the most important in summer and autumn. While in autumn and winter evaporation is mainly affected by average relative humidity, sunshine duration, and total cloud cover jointly.