京津风沙源区1959-2011年潜在蒸散气候敏感性的时空变异

基于Penman-Monteith公式和京津风沙源区及周边46个气象站1959-2011年逐日气象数据,分析了潜在蒸散对气温、风速、日照时数和相对湿度的敏感性及其时空变化规律。结果表明:(1)年尺度潜在蒸散对最高气温最为敏感,其次是相对湿度,对风速最不敏感;季节尺度最高气温和日照时数敏感系数的高值发生在夏季,最低气温、风速和相对湿度敏感系数的高值发生在冬季。(2)空间尺度潜在蒸散对最高气温、最低气温和相对湿度的敏感性表现为从东北向西南减少,而对日照时数表现为增加。(3)京津风沙源区1959-2011年潜在蒸散对气温的敏感性呈下降趋势,而对风速、日照时数和相对湿度的敏感性呈增加趋势。(4)气温的敏感性随温度升高而下降,而日照时数和相对湿度的敏感性随光照和湿度下降而升高。

Temporal-spatial Change of the Sensitivity of Potential Evapotranspiration to Climatic Influencing Factors in Beijing-Tianjin Sand Source Control Project Zone

In this paper, based on daily data at 46 meteorological stations within and around the Beijing-Tianjin Sand Source Control Project Zone during 1959-2011, the sensitivity of potential evapotranspiration to variation of air temperature, wind speed, sunshine duration and relative humidity at different timescales was identified by using the Penman-Monteith equation and non-dimensional sensitivity coefficient. (1)Annual potential evapotranspiration was most sensitive to maximum air temperature, followed by relative humidity, wind speed was the least sensitive variable; In terms of season, the high values of sensitive coefficients of potential evapotranspiration to maximum air temperature and sunshine hours occurred in summer, and the high values of sensitive coefficients of potential evapotranspiration to minimum air temperature, wind speed and relative humidity occurred in winter. (2) The sensitive coefficients of potential evapotranspiration to maximum air temperature, minimum air temperature and relative humidity showed decreasing trend from northeast to southwest, while the sensitive coefficients of potential evapotranspiration to sunshine hours showed increasing trend from northeast to southwest. (3) During 1959-2011, the sensitive coefficients of potential evapotranspiration to maximum air temperature and minimum air temperature showed decreasing trends, while the sensitive coefficients of potential evapotranspiration to wind speed, sunshine hours and relative humidity showed increasing trend. (4) The sensitive coefficients of potential evapotranspiration to maximum air temperature and minimum air temperature decreased with increase of the maximum air temperature and minimum air temperature, while the sensitive coefficients of potential evapotranspiration to sunshine hours and relative humidity increased with decrease of the sunshine duration and relative humidity.