NO. lO SOLAR RADIATION AND WEATHER STUDIES ABBOT OQ 



and precipitations at numerous terrestrial localities. The inference is 

 that solar changes influence weather. 



5. Changes of phases and amplitudes occur in these terrestrial 

 periodicities. 



6. The changes of phases and amplitudes in these terrestrial peri- 

 odicities occur at integral multiples of ii| years measured from 

 January 1819. 



7. On account of the integral relationships of the terrestrial peri- 

 odicities to 23 years, the weather at all stations contains features which 

 tend to repeat themselves at intervals of 23 years. 



8. On account of reversals of phase of some of the periodicities at 

 23-year intervals rather than at ii^-year intervals, some of these 

 features are more accurately reproduced at intervals of 46 years than 

 at those of 23 years. 



9. Various phenomena depending on weather show the influence of 

 the 23-year cycle. Among those examined are the level of the Nile 

 River, the levels of the Great Lakes, the rainfall of Southern New 

 England, the widths of tree rings, the abundance of cod and mackerel, 

 the thickness of varves of Pleistocene and Eocene ages. 



10. From tabular and graphic representations of departures from 

 the normal in both temperature and precipitation for more than 100 

 stations, the weather' itself has disclosed many features which repeat 

 themselves in cycles of 23 years, and which though obscured by modi- 

 fications of phase and amplitude may support predictions of future 

 weather conditions. 



11. Forecasts based on these relations having been made to cover 

 the years 1934, 1935, and 1936 for more than 30 stations in the United 

 States, these forecasts are fairly well verified both as to temperature 

 and precipitation in 1934. 



