232 



ABBOT: SOLAR RADIATION MEASUREMENTS 



weather of Argentina. His studies have great variety. They 

 deal especially with the discovery of periodicities in the phe- 

 nomena which he treated by harmonic analyses as well as by 

 simpler methods. 



TABLE I. 

 Relation Between Rainfall and "Solar Constant." 



Solar changes in 

 calories 



+0.050 to +0.070 

 +0.030 to +0.050 

 +0.010 to +0.030 

 — 0.0 10 to — 0.030 

 ).030 to — 0.050 

 ).05o to — 0.070 



Average daily rainfall in mm. 



Mean 



In December, 191 8, Clayton began to employ the results fur- 

 nished by the Smithsonian observers at Calama, Chile, for actual 

 forecasting. Fully convinced of the value of such data. Prof. 

 C. C. Wiggin, Chief of the Argentina Weather Service, arranged 

 for a daily telegraphic service from Calama to Buenos Aires. 

 By their great skill and zeal, Messrs. Moore and Abbot, the 

 Smithsonian observers at Calama, have completely reduced the 

 "solar constant" value on each day of observation. They send 

 a code telegram from Calama via Antofagasta and Valparaiso, 

 Chile, to Buenos Aires on the evening of each observing day. 

 This states the intensity of solar radiation outside our atmos- 

 phere, and the quality of the determination. The value is 

 available in Buenos Aires for the forecasting on the following 

 morning, within 24 hours of the time of observation. 



Fortunately, during my visit at Calama in June, 1919, with 

 the cooperation of the observer there, I was able to perfect a 



