JOURNAL 



OF THE 



WASHINGTON ACADEMY OF SCIENCES 



Vol. II, OCTOBER 19, 1912 No. 17 



METEOROLOGY. — Solar radiation intensities at Madison, Wis. 

 H. H. Kimball and E. R. Miller. To appear in full in 

 the Bulletin of the Mount Weather Observatory. 



Since July 19, 1912, measurements of the intensity of the solar 

 radiation received upon a surface normal to the direction of the 

 incident solar rays have been made at the Weather Bureau office, 

 Madison, Wis., on days when the sky was free from clouds. 



A Marvin pyrheliometer, standardized by comparison with a 

 Smithsonian silver disk pyrheliometer, has been employed in 

 making the measurements. A brief description of this pyrheli- 

 ometer will be found in the Bulletin of the Mount Weather Obser- 

 vatory, volume 3, page 81. The instrument has been exposed on 

 shelves outside the office windows at an elevation of 974 feet 

 above sea level. The latitude of Madison is 43° 05' north. 



The monthly means of a.m. and p.m. measurements are given 

 in table I, each mean being the average of measurements obtained 

 on not less than three different days. 



The monthly means of a.m. and p.m. measurements made at 

 Washington, D. C, with an Angstrpm pyrheliometer, have been 

 published in the Bulletin of the Mount Weather Observatory, 

 volume 3: pages 86 to 91, inclusive. To facilitate comparison, 

 these have been reduced to the Smithsonian standard by dividing 

 by the factor 0.95, and the results are given in table II. 



It will be seen from these tables that while the monthly aver- 

 ages of radiation intensities for Washington and Madison differ 



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