266 Bigelow — Radiation in the Earth's Atmosphere. 



cloud region where the ice crystals ascending in the vertical 

 convectional currents accumulate in layers just below the iso- 

 thermal region, and intercept and store up some of the out- 

 flowing heat from the lower levels as well as incoming solar 

 radiation. The fall of Qj-Q,, is faster in the isothermal 

 region than in the strata below it. The courses of the pres- 

 sure P and the radiating energy K diverge slowly with the 

 height, but the function connecting them can evidently be 

 worked out, so that the computation between them may be 



Fig. 3. Pressure, Kadiation and Exponent A. 



Entropy S, work W, and inner energy U are similar to Q ; log C is similar 

 to A. Continuous lines are for Europe and broken lines are for the Tropics. 



shortened. The value of A has a maximum value 5*30 at 

 5,000 meters, a minimum at 10,000 of 3*82 which corresponds 

 with the normal temperature gradient for radiation in the free 

 air, with one end on the surface and the other in the isother- 

 mal region. As these values of A depend upon the temper- 

 ature gradients and so upon the ratio TyT,,, it follows that the 

 change of T a from its normal value for A = #=3*82 must be 

 due to special supplies of heat locally applied, as from the sur- 

 face and the lower aqueous vapor, or from the heat stored up 

 by congestion in the isothermal region. The relation of A to 

 a at any level, therefore, becomes a means for studying the 

 local as distinguished from the planetary radiation. The heat 

 of the isothermal level is apparently due to a combination of 

 the processes of hydrostatic pressure, circulation and physical 

 rate of radiation through cold strata, 207° to 210°, to balance 

 the total dynamic inward force of the earth's gravitation. 



Oficina Meteorologica Argentina, 

 Cordoba, Argentina, S. A., March, 1912. 



