Path Analysis on Evaporation Variation Characteristic and the Impacting Factors in Benxi Hilly Area during Recent 58 Years

Based on the data of annual evaporation, temperature, precipitation, sunshine, wind speed and vapor pressure of weather station in Caohekou, Benxi from 1953 to 2010, and using methods of climatic trend, path analysis of the evaporation and affecting factors was conducted. The result showed that annual evaporation showed a significant increasing trend and its linear trend rate 25.64 mm/10 a. Meteorological factors affecting evaporation were orderly as precipitation, air vapor pressure deficit, annual temperature range, average annual temperature, wind speed, and sunshine. Annual precipitation and other meteorological factors also affected the evaporation greatly. The increase in evaporation was mostly resulted from reduction of sunshine duration, wind speed and warming-drying trend.