Table 149 (concluded) 



439 



TOTAL SOLAR AND SKY RADIATION ON A HORIZONTAL SURFACE DURING 



CLOUDLESS CONDITIONS 



AIR MASS ( m,) 



Table 150 



RELATION BETWEEN THE VERTICAL COMPONENT OF DIRECT SOLAR 



RADIATION AND TOTAL SOLAR AND SKY RADIATION ON A 



HORIZONTAL SURFACE 



By means of pyrheliometers Kimball 1 measured the vertical component of direct solar 

 radiation and also the total solar and sky radiation on a horizontal surface for cloudless 

 skies. Table 150 gives the ratio of the vertical component of direct solar radiation to the 

 total radiation received on a horizontal surface as a function of the sun's zenith distance, 

 based on the weighted mean of measurements at Washington, D. C, Lincoln, Nebr., and 

 Madison, Wis. 



Sun's zenith distance 



Ratio 



•Kimball, H. H., Month. Weath. Rev., vol. 47, p. 769, 1919. For variation with height see Klein, 

 W. H., Journ. Meteorol., vol. 5, p. 119, 1948. 



SMITHSONIAN METEOROLOGICAL TABLES 



