THE LIGHT EQUIVALENT OF TOTAL SOLAR RADIATION AND ITS APPLICATION IN THE CALCULATION OF ILLUMINATION CLIMATOLOGY

From 1983 to 1984,14 solar radiation observation stations which are located in different climate zones were chosen for the simultaneous observation of natural illumination with the hourly observation of insolation every day.In this paper,according to the data the light equivalent of total solar radiation (LEOTSR) has been given.A multivariate regression equation is employed to calculate the annual and monthly mean values of the LEOTSR at 14 observation stations.The variables of the equation include latitude,elevation,surface mean absolute humidity and sunshine duration.The results show that the relative errors are less than 10%.The LEOTSR for 464 observation stations was calculated by means of the multivariate regression equations which were obtained by the data of 14 observation stations.The total illumination is given by the LEOTSR multiplying the total radiation.The climatological values of total illumination for each station are also calculated according to its LEOTSR and solar radiation.Finally,the climatological charts of total illumination in China have been drawn.