The results are shown at right in Fig. 8. As seen in the diagram, 

 some retardation of wind velocity takes place in the inversion layer, 

 as the air moves from the first point (H' = 400 m.) to the next point 

 (H' —500 m.). This causes ascending motion of the air in order to 

 establish continuity. 



For example, take the distance between two points as 10 km., then 

 the magnitude of ascending component of the air at each height becomes 

 such as illustrated at left in Fig. 8. 



Ascend/nq 



Ve hoit-y 



-r r 



V^incf Ve.foci'^y in 



Fig. 8. 



r 

 /yysEc 



Thus it has been proved that ascending component exists in the air 

 which moves over successively colder and colder water surface and 

 consequently sea fogs are produced in the same way as ordinary cloud. 



Indeed, sea fogs are much alike to the cloud which is formed in weak 

 ascending current of the air, and accordingly sea fogs should be regarded 

 as a type of cloud which forms at small distance above sea-level and 

 often builds down to sea-level on account of very high humidity of the 

 air over the sea. 



ON THE MECHANISM OF HEAT THUNDERSTORMS AND SOME 

 PROPERTIES OF CUMULO-NIMBUS IN JAPAN 



By S. Sakuraba, Central Meteorological Observatory, Japan 



The heat thunderstorm which occurs most frequently in summer is 

 investigated by aerological data, and some properties of cumulo-nimbus 

 are discussed by the data from a dense network of observation points 

 in the Kwanto District, Japan. 



77 



