208 



[chap. 4 



transfer, even though it is a small term on the balance sheet. Its importance lies in 

 facilitating the evaporation and turbulent momentum exchange. 



There is some evidence (Woodcock and Wyman, loc. cit.) that these buoyant, 

 low-level eddies are organized, possibly into the polygonal or long roll type 

 configurations of Benard (1900) so beautifully illustrated by the laboratory 

 experiments of Avsec (1939). The natural attempt of the 1946 Woods Hole 

 expedition to relate these to trade-cumulus patterns, however, failed com- 

 pletely and in so doing led to further expeditions and much of the material on 

 air-sea interaction contained in this chapter. The reason for the failure is 

 brought out in Fig. 52, which shows the typical vertical temperature and 

 moisture structure up to the inversion. 



2400 



2200 



2000 



1800 



1600- 



1400 



1200 



X 1000 



800 



600 



400 



200 



6 8 10 12 14 16 18 20 22 24 26 6 8 10 12 14 

 Temperature, C I Mixing Ratio, g/kg 



Fig. 52. Typical vertical temperature and moisture sounding of the western Atlantic 

 trade-wind region. Made at 19° 30'N, 66°W by Woods Hole aircraft on April 27, 1946. 

 (After Bunker et al., 1949, Fig. 58.) 



Dry and wet-bulb temperatures in °C ; mixing ratio (approximately equal to 

 specific humidity) in g/kg. All are functions of height in meters. Sounding shows normal 

 structure of moist layer up to inversion base under conditions of strong trade. Surface 

 wind from 080°, 17 mph. Sea minus air temperature 0.5°C. Cumulus base about 

 2500 ft. Sounding made in clear space between cloud groups. 



