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of the anticyclone, slight wanning of the sea surface is expected partly due 

 to latitudinal warm advection and partly due to low sea-air exchange and 

 high insolation. 



Subsequent changes in the atmosphere . Assuming that the advectional and 

 local heating effects, described above, are not in equilibrium with the cool- 

 ing and heating processes and advectional anomalies result, the following 

 further changes could be expected in the atmosphere: 



In the W and TTW part of an anticyclone the warm advection would counter- 

 act the heat loss of the air by decreasing sea-air temperature difference, 

 and the expected pressure fall would be slowed down with time. If the warm 

 water advection is especially strong, a pressure rise in the N part of the 

 anticyclone could be observed in a few days, resulting in an apparent slight 

 northward movement of the high. 



In the NE and E part, the cold water advection would diminish and/or 

 counteract the increase of sea-air exchange. The same effect occurs in the 

 E and SE part, thus counteracting the prospective accompanying pressure rise 

 and eastward movement of the high. This mechanism might explain the quasi- 

 stationary nature of highs in the lower latitudes over the oceans . 



Cyclonic circulation : 



Atmospheric circulation in relation to the heat exchange . In the W and 

 SW part of a cyclone, high positive sea-air exchange is taking place, due to 

 the southward component of cool, drier air across the sea surface isotherms. 

 This cool air is usually accompanied by subsidence which results in clear, 

 cloudless skies. The high sea-air exchange is accompanied by relatively rapid 

 pressure rises in this sector. 



In the S part of a cyclone, the air flow is nearly parallel to the sea 

 surface isotherms or with a slight northerly component, which increases in 

 the SE part of the cyclone and results in heat and moisture loss by the air, 

 accompanied by pressure falls . 



In the E and NE part the flow is towards colder sea surface temperatures . 

 The heat loss by air is, however, decreasing rapidly, because of cooling of 

 the lower layers of the air and creation of stable conditions. 



In the W part of the cyclone the curvature is usually relatively sharp 

 and in the WW part the heating of the air starts again due to a slight 

 southerly component. 



Cha nges in the ocean caused by advection and heat exchange . In the W 

 and SW part of a cyclone, cool sea surface advection taJces place. This cool- 

 ing is further aggravated by deep mixing in the sea due to heavy winds and 

 waves and by heat loss from the sea through sea-air exchange. 



In the S and SE part an E to NE advection of warmer water occurs, which 

 is accompanied by low heat loss or occasionally heat gain through sea-air 



