TABLE 48. THE POROSITY OF ICE (IN PERCENTAGE OF VOLUME) WHEN THE 

 SALT CELLS ARE REPLACED WTIH AIR 



TABLE 49. GAS CONTENT OF THE SEA ICE OF THE BARENTS SEA 

 (IN PERCENTAGE OF VOLUME) 



The ratio of the oxygen and nitrogen content which saturates sea water at all temperatures 

 and salinities is approximately 0.5; the same ratio in air is approximately 0.264. The total con- 

 tent of oxygen and nitrogen which will saturate sea water of various salinities at freezing tem- 

 perature fluctuates within the limits of 2.2 to 2.9 per cent by volume. Therefore, it should be 

 concluded that the hollows in the sea ice are mainly filled with the air of the atmosphere, where- 

 upon the amount of oxygen in it is lowered and the amount of carbon dioxide is raised, * in all prob- 

 ability by the respiration of organisms contained in sea ice and by oxidation processes. 



As the investigations of Deriugin and Bruns indicated, the distribution of the gases even in 

 ice formed under calm conditions is extremely nonuniform and the least porosity is observed in 

 the middle part of the ice . 



According to the investigations of Amold-Aliabev, the air content within the ice of the Gulf 

 of Finland fluctuates within the limits of 4 per cent by volume, whereas in the ice of the Barents 

 Sea, the air contained 8 per cent and higher. The distribution of air bubbles in the separate pieces 

 of ice is very uneven as can be seen from figure 57. 



An exception to the indicated rule, is old ice which during the course of its existence had 

 undergone strong compression which had gradually forced the brine and particularly the air bub- 

 bles out of the ice and had turned such ice into a solid monolithic mass. 



*Bruns indicates that the amount of carbon dioxide is evidently still greater inasmuch as a 

 part of the carbon dioxide dissolves in water when the air bubbles are freed from melting ice. 



167 



