GEOGRAPHICAL DISTRIBUTION OF TEIMPERATURE— SEA-LEVEL. 



37 



latitude 67° S. the sea is completely frozen over, but the ice is broken up by a few cracks. 

 South of latitude 78° S. we have the Barrier surface. 



60 



150°W.Lon| 



10" 



TEMPERATURt 



Flo. II. Temperature clistribiition along 150^ \V. longitude. 



In figure 11 the character of the ice along 150° W. is shown. Hero again we have open 

 water north of about latitude 64° S. Then the belt of loose pack followed by sea ice inter- 

 sected by opening and closing leads. It is almost certain that south of 70° S. on this 

 meridian there is permanent heavy ice either in the form of a Barrier or of a snow-covered 

 land. Therefore south of this latitude the surface conditions will be similar to those on the 

 Barrier. 



On each of these diagrams there has been superposed a curve of temperature, the ordi- 

 nates being latitude and the abscissa? temperature. Examining figure 10 we see that north 

 of latitude 65° S. the temperature falls slowly with increase of latitude. In latitude 65° S. 

 the loose pack is entered and the ice causes a rapid fall of temperature which continues 

 as we proceed south until the more or less completely frozen centre of the Ross Sea is 

 reached in latitude 67° S. From here onwards towards the south the temperature de- 

 creases very slowly until the Barrier is reached in latitude 78° S. The discontinuity of 

 temperature at the Barrier edge is shown by the temperature running horizontally for 15°F. 

 From the edge of the Barrier towards the south the temperature again falls slowly. 



