YANG Gui-yu, WANG Zhi-sheng, WANG Hao, JIA Yang-wen. Potential evapotranspiration evolution rule and its sensitivity analysis in Haihe River basin[J]. Advances in Water Science, 2009, 20(3): 409-415.
Citation: YANG Gui-yu, WANG Zhi-sheng, WANG Hao, JIA Yang-wen. Potential evapotranspiration evolution rule and its sensitivity analysis in Haihe River basin[J]. Advances in Water Science, 2009, 20(3): 409-415.

Potential evapotranspiration evolution rule and its sensitivity analysis in Haihe River basin

  • Based on the daily climatic data from the nation weather station in 1956-2000,the paper employs the P-M equation and the sensitivity coefficient method to analyze the evolution rule of the potential evapotranspiration(ET0)and the sensitivity relation of ET0 to climatic variables in Haihe River basin.The results indicate that the annual ET0 series appears decreasing trend with four different sub-stages in the recent 45 years.The multi-annual ten-day average ET0 shows inverse "V" shape, and 61.6% of the whole ET0 amount occurs in the middle-April to the up-August.In space,the multi-annual ten-day average and the annual ET0 have an increasing trend from the upstream to the downstream.Compared with the evolution rule of the climatic variables and the sensitivity of ET0 to them,the evolution rule of the annual ET0 in the whole basin is similar to that of the multi-annual average wind speed,sunshine time and short wave radiation,and inverses to that of the multi-annual average temperature.The evolution rule of the multi-annual ten-day average ET0 has same trend to that of the temperature,actual vapor,and sunshine time,as wel as the short wave radiation.However,in all the sensitivity coefficient of ET0 to these climatic variables,that of ET0 to short wave radiation is maximum in the whole year and the second water resources districts.The sensitivity of the ET0 to any other climatic variables is different in time and space,and the values of sensitivity coefficients vary greatly.According to the analysis above,the ET0cs decreasing trend in the whole basin may be caused by the change of short wave radiation and sunshine time.
  • loading

Catalog

    /

    DownLoad:  Full-Size Img  PowerPoint
    Return
    Return