16 



TEMPERATUKE OP THE SURFACE "WATERS OF THE ATLANTIC OCEAN 



considered a purely dynamic system in the North 

 Atlantic C. It extends, according to the previously 

 mentioned investigation of Felber, on the average 

 between 30° N. and 35° N. from 75° W. to 20° W., that 

 is, in an area of relatively small temperature differences. 

 In contrast to the south, where the convergence runs 

 from the Argentine coast to the Indian Ocean, in 

 other words, across almost the whole breadth of the 



our present knowledge undergoes only shght changes of 

 position, and because of the greater strength of the cur- 

 rents, especially between Brazil and Falkland Currents 

 and between Agulhas Current and west wind drift, is 

 limited to a very narrow strip. An investigation of the 

 currents of the South Atlantic Ocean according to one- 

 degree fields, in contrast to results obtained from using 

 the two-degree fields of the Dutch atlases, might reveal 



Atlantic water 



^ — — — — Mijeil water 



3 Polar water 



Eeykjanaes ridge, about 1600 m. 



Figure 17. — Diagram of the average water movement in the Irminger Sea and Denmark Straits in August, ba.sed on distribution of 

 temperature, saline content, and density, according to tlie data obtained on the Meteor fishery patrols. 



Atlantic Ocean, it does not reach from coast to coast. 

 In the west it is broken through by the Gulf Stream, and 

 in the east by the Canary Current. According to 

 Felber, there is no annual periodicity, but rather this 

 front, formed by the weak and unstable currents (often 

 under 5 nautical miles in a day's reckoning), swings 

 irregularly back and forth in the area marked on the 

 chart (fig. 16). In this respect also it differs from the 

 southern subtropical convergence, which according to 



certain deviations, but it would probably show only 

 minor changes in the fundamental difference between 

 the northern and southern subtropical convergence as it 

 has been established. 



While the subtropical boundary B forms the northern 

 boundary of the Gulf Stream, the subtropical conver- 

 gence C represents its southern boundary, up to 

 which point the water masses extend and then curve off 

 from it into the Sargasso Sea. 



