XIX 



THE INTERCHANGE OF HEAT AT THE SURFACE OF 

 THE EARTH AND IN THE ATMOSPHERE 



BY PROF. DR. WM. VON BEZOLD 



[Sitz. Ber. of the Berlin Academy of Sciences for i8q2, pp. 113Q-UJ8. Trans- 

 lated from Gesammelte Verhandlungen, Berlin, igo6, pp- 316— 356] 



(I.) INTRODUCTION. 



The "distribution of heat at the earth's surface" or, more correctly, 

 "the distribution of temperature in the lowest strata of the atmos- 

 phere" has been the object of many exhaustive investigations since 

 the days of Alexander von Humboldt. 



It is especially Dove, Wild, and Hann who have gradually com- 

 pleted the idea that was sketched out in a few lines by Humboldt 

 and have worked out its details for a large portion of the surface of 

 the earth. 



In this way we have learned at least in general of those influences 

 that, together with the predominant radiation from the sun, deter- 

 mine the distribution of heat, and thus give the lines of equal 

 temperature (isotherms) the exact form that we find in the charts 

 drawn by the above-mentioned investigators. 



But in general these studies are confined to purely qualitative 

 considerations. One is satisfied to state the general trend of the 

 influence of the distribution of land and water, and of the currents 

 of air and ocean. Hitherto only to the most modest extent have 

 attempts been made to determine the numerical or quantitative 

 extent of these influences, or to consider together the general 

 economy of the heat in the atmosphere and on the earth's surface. 



In this respect a section of Samuel Haughton's Physical Geog- 

 raphy must be first mentioned. 1 To a certain extent the works of 

 Zenker* belong to this subject. We also meet with attempts in this 





1 Samuel Haughton: Six lectures on physical geography. Dublin and 

 London, 1880. 



2 Zenker: The distribution of heat at the earth's surface. Berlin, 1888; 

 also Met. Zeit., 1892, IX, pp. 336-344, 380-394. 



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