196 MAEIOX EXPEDITION TO DAVIS STRAIT AND BAFFIN BAY 



as the eye could reach. The physical state of the water column was 

 as follows: 



While the temperatures, .surface to bottom, was practically alike, 

 the salinity of the upper 15 meters Avas very much lower in the melt- 

 ing ice field than it was to the southward, causinjj the densitv of the 



The Stability of a Water Mass in the Ice Regions 



FiGUEE 110. — The distribution of density which was found on February 28, 19l!l. near 

 Cape Race. Newfoundland, along the southern edge of a field of melting pack ice. 

 The marked stability of the water layers, at the time, precludes any interchange of 

 light-thaw water from the surface with the heavier water near tlie bottom. 



surface layers — a mixture of thaw water Avith sea water — to be 

 correspondingly lower."" The fact that these results show no such 

 distribution of temjierature and salinity as would follow from Pet- 

 tersson's tank experiment is evidence that natural conditions 

 were not fully simulated in his laboratory exiDeriment. The pro- 

 portions of thickness of ice to dej^th of sea, the distribution of 



"" Ricketts (1030, p. 120). in discussing the conditions around a nu'lting ici'bcrg observed 

 by the ice patrol south of Newfoundland, concludes that the prevailinu distrilmtioii of tem- 

 perature and salinity in the sea with depth hydrostaticallv prevents the establishment of 

 a vertical circulation. 



