560 Tables 696 and 697.— THE EARTH'S ATMOSPHERE 



The following condensed tables (Maris, Terr. Mag. and Atmosph. Elec, 33, 233, 1928) 

 of the upper atmosphere of the earth result from attempts at including further factors than 

 usually considered. They should be taken as tentative because of approximate theory and 

 ignorance of much necessary data for the discussion. Meteors, reflection of sound and radio 

 waves, the aurora, ozone, ionization, and optical phenomena continually give us further 

 probes into the upper air. The gases are uniformly mixed below a height of roughly 100 km; 

 above 150 km each gas is in equilibrium with its own partial pressure; between these heights 

 there is for each gas a transition from uniform mixture with the air to equilibrium with its 

 own partial pressure at a height which depends on the temperature and previous wind cur- 

 rents of the atmosphere, but which averages about no km. Apparently above 300 km the 

 atmosphere can not be assumed in equilibrium; the percentage of very high-energy molecules 

 is far higher than indicated by a Maxwellian curve for thermal equilibrium. 



Smithsonian Tables 



