G. I. TAYLOR ON EDDY MOTION IN THE ATMOSPHEEE. 



Having obtained the path of the air, the next step is to find the temperature of the 

 sea below it. This is a comparatively easy matter, for a careful watch is kept by the 

 liners on the temperature of the North Atlantic. The results of their observations are 

 plotted by the Meteorological Office on weekly charts, on which isothermal lines are 

 drawn to represent sea temperatures of 80 F., 70 F., 60 F., 50 F., and 40 F. These 

 charts are published on a small scale in the weekly weather report of the Meteorological 

 Office, but Captain Campbell Hepworth was kind enough to lend me the originals, and 

 on them I plotted the air paths. 



One of the charts, with the air's path marked on it, is shown in fig. 1.* 

 It has been found that the temperature of the air rarely differs from that of the 

 surface of the sea by more than 2 C., and usually the difference is only a fraction of 



Path of air and sea temperature for kite ascent of August 4th. 



Fig- I- 



a degree. The temperature of the "base of the atmosphere at any point along the 

 air's path has, therefore, been assumed to be that of the surface of the sea. In many 

 of the kite ascents the temperature of the sea, and therefore of the surface air, 

 increased up to a certain point along the air's path and then began to decrease. 

 While the air was moving along the first part of the path its temperature might be 

 expected to decrease with height at a rate greater than the adiabatic rate.t When 



* Others are reproduced in the 'Report of the "Scotia" Expedition, 1913.' 



t If the temperature of the air diminishes at the adiabatic rate of 10 G. per kilometre, its potential 

 temperature is constant, so that no amount of eddy motion can transfer heat either upwards or 

 downwards. 



