AN ATTRIBUTION ANALYSIS OF CHANGES IN POTENTIAL EVAPOTRANSPIRATION IN THE BEIJING-TIANJIN-HEBEI REGION UNDER CLIMATE CHANGE

作者：于占江,周偉燦,張曉

摘要：Based on the measurements obtained at 64 national meteorological stations in the Beijing-Tianjin-Hebei(BTH) region between 1970 and 2013, the potential evapotranspiration(ET0) in this region was estimated using the Penman-Monteith equation and its sensitivity to maximum temperature(Tmax), minimum temperature(Tmin), wind speed(Vw), net radiation(Rn) and water vapor pressure(Pwv) was analyzed, respectively. The results are shown as follows.(1)The climatic elements in the BTH region underwent significant changes in the study period. Vwand Rndecreased significantly, whereas Tmin, Tmaxand Pwvincreased considerably.(2) In the BTH region, ET0 also exhibited a significant decreasing trend, and the sensitivity of ET0 to the climatic elements exhibited seasonal characteristics. Of all the climatic elements, ET0 was most sensitive to Pwvin the fall and winter and Rnin the spring and summer. On the annual scale,ET0 was most sensitive to Pwv, followed by Rn, Vw, Tmaxand Tmin. In addition, the sensitivity coefficient of ET0 with respect to Pwvhad a negative value for all the areas, indicating that increases in Pwv can prevent ET0 from increasing.(3)The sensitivity of ET0 to Tmin and Tmax was significantly lower than its sensitivity to other climatic elements. However,increases in temperature can lead to changes in Pwv and Rn. The temperature should be considered the key intrinsic climatic element that has caused the'evaporation paradox'phenomenon in the BTH region.

發文機構：Nanjing University of Information Science and Technology Shijiazhuang Meteorological Bureau College of Resources and Environment

關鍵詞：BEIJING-TIANJIN-HEBEIregionCLIMATEchangepotentialEVAPOTRANSPIRATIONCLIMATICelementsensitivityCOEFFICIENT

分類號： P426.2[天文地球—大氣科學及氣象學]