青藏高原晴天太阳直接辐射的计算和分析

本文根据1979年5～8月青藏高原气象科学实验资料,研究了利用卡斯特洛夫公式计算青藏高原晴天太阳直接辐射的有关问题。首先从原始资料中挑选出晴天太阳直接辐射并计算其日平均辐照度,然后以此为标准,利用迭代法反求可能太阳直接辐射日平均辐照度理论公式中的系数C,建立该系数与平均水汽压的经验公式,再利用经验式反演晴天太阳直接辐射。本文还比较了由乌克兰英采夫法确定的可能太阳直接辐射与实际晴天太阳直接辐射的差异,证实前者要比后者偏大,其偏离程度随站点拔海高度增加而缩小。文中最后讨论了青藏高原晴天太阳直接辐射日平均辐照度的地理分布,并分析了其随拔海高度的变化。

CALCULATION AND STUDY OF DIRECT SOLAR RADIATION FROM THE CLEAR SKIES OVER THE QINGHAI-XIZANG PLATEAU

According to the data from the scientific experiment of meteorology in the Qinghai-Xizang Plateau from May to August in 1979, the questions have been studied concerning the direct solar radiation from clear skies ( DSRCS ) over the Qinghai-Xizang Plateau by use of Kast-rov's formula. First of all, the daily-averaged irradiance of DSRCS are determined by means of the data which are elected from the original records and are the values from the clear skies, and with these values obtained as a basis all values of C, a coefficient that appears in Kastrov's formula, are found out by means of the iterative technique for individual stations and months. Then, the empirical expression related C to vapor pressure is worked out. Finally, the DSRCS can be satisfactorily retrieved by use of this expression. In addition, the differences between the possible direct solar radiation determined by use of the wucraintzev approach and the measurements from clear skies are shown in the paper and it is proved that the former is greater than the latter and that the differences reduce as the elevation of the stations rises. In the end of this paper, the geographical distributions of the daily-averaged irradiance of DSRCS over the Qinghai-Xizang Plateau are discussed and the variation of the DSRCS with elevation is analysed.