OCEANOGRAPHY AND SEA-ICE 



tongue two hundred miles from the main Ice Cap (see 

 Fieure 22). At the other end of the submerged ridge 

 is a large ice shelf to the west of Davis Sea. Off 

 Adelie Land is that curious pair of giant tongues, the 

 Mertz and Ninnis glaciers, of which the latter is so ir- 

 regular that it has some of the appearance of a relic of 

 a sheet of ice shelf. So also the great Ross Ice Shelf 

 lies just south of the submerged plateau of the Ross 

 Sea. At the Ice Flood Epoch possibly the sea waters 



so so A-O 



Fig. 23. — Vertical section of ocean north of Gauss- 

 berg, SHOWING stratification OF WATER. 



Warm waters are dotted. Depths in meters. (After Drygalski.) 



were locked up in the enlarged ice cap to such a degree 

 that the shallowest part of the Pennell Bank was only 

 two hundred feet below the then level of the sea. There 

 is little doubt that the much larger Ross Ice Shelf at 

 that epoch would be driven high out of the water over 

 this shallow bank. 



Ocean Currents 

 Drvsralski shows that the effective cooling of Ant- 



-*fe* 



arctic waters is confined to certain layers of the 

 southern ocean 



^ 161 



He gives a section of the Indian 



