【摘要】 利用中国科学院大气物理研究所香河大气综合观测实验站(39°47′N,116°57′E)2004年10月至2005年12月共15个月的太阳辐射观测资料,分析了该地区光合有效辐射与太阳总辐射比值的(PAR/Rs)日变化和季节变化特征,得出月平均PAR/Rs值变化范围在1.808~2.048μE.J-1之间,最大值出现在夏季,最小值出现在冬季,年平均值为1.948μE.J-1。提出了一个利用太阳总辐射观测值计算光合有效辐射瞬时值的参数化算式,用该算式计算得到的PAR与实际观测值的均方根误差为19.28μE.m-2.s-1,有96%的计算值与观测值偏差在±10%以内。比较了香河地区与太湖地区、额济纳地区光合有效辐射瞬时最大值、小时累积最大值及日累积最大值的差异。更多还原

【Abstract】 Based on the 15 month spans of solar radiation data in Xianghe Atmospheric Observation Station of Institute of Atmospheric Physics,Chinese Academy of Sciences(39.47°N,116.57°E) from October 2004 to December 2005,the diurnal and seasonal variations of the ratio of PAR to global radiation(PAR/R_s) are analyzed.The ratio ranges from 1.808 to 2.048 μE·J-1,with an annual mean value of 1.948 μE·J-1.It decreases from the largest to the smallest as season changes from summer to winter.A new simple and efficient function which only requires the observation of global irradiance is derived to calculate the instantaneous PAR.The root mean square error between calculated and measured PAR is 19.28 μE·m-2·s-1 and about 96% of the calculated values agree with measurements within 10%.Finally,the maximum daily and hourly calculative values,maximum instantaneous values of PAR,measured over Xianghe,Taihu and Ejina regions are compared and the differences are analyzed.更多还原