36 



TEMPEKATURE. 



over the centre of the Ross Sea than either in McMurdo Sound or at Cape Adare. AVe also 

 know that during the winter open leads often form in the sea to the north of Cajie Crozier. 



Fig. 10. Temperature distribution along ISO" E. longitmle. 



We are therefore quite safe in assuming that the mean temperature over the centre of the 

 Ross Sea is somewhat liigher than at Cape Evans and at Cape Adare. The centre of the 

 Ross Sea has therefore been encircled by the — 10°F. isotherm. The discontinuity of tem- 

 perature at the edge of the Barrier found to exist in McMurdo Sound by the Cape Crozier 

 Party is much more likely to exist along the main edge of the Barrier ; hence we have here 

 a temperature discontinuity with several i.srtherms following the edge of the Barrier too 

 close to be separated. The sea ice is probably very thick near Framheim during the winter 

 as it forms early, and the atmosphere is still and cold in this region. Hence it is probable 

 that the isotherms open out near Framheim in the manner shown in the map. 



The physical meaning of the temperature distribution which is shown by the isotherms 

 for July will probably be made more clear and convincing by setting out the temperature 

 distribution in another way. The character of the ice along the meridians 180° E. and 

 150° W. is .shown diagrammatically in figures 10 and 11. The former meridian runs down 

 the centre of the Ross Sea and the diagram, figure 10, shows open sea north of about 

 latitude G4° S., then a belt of loose pack gradually getting more dense until in about 



