340 PETTEltSSON, SIBERIAN SEA. 



quence of this is also to be seen in the graphic illustration 

 on section I, viz. that the ice at the surface is prevented 

 from melting by the vi,cinity of the ice-cold water a score of 

 metres below. Just at those places indicated in section I, 

 where the isothermal lines of — 2"" and — 1°.8 rise from the 

 deep to within 20 metres from the surface, the Vega encoun- 

 tered väst ice-floes. In his report to Dr. Oscar Dickson 

 Nordenskiöld writes:^ 



»I had long indulged in the hope of reporting, that we 

 had arrived at the Yenisei without meeting with a single 

 block of ice. At our arrival at the latitudes of Beli Ostrow, 

 however, waves and wind died away in a manner, which 

 unmistakably indicated the presence of ice. Subsequently we 

 encountered väst floes of drift ice, which, however, were suffi- 

 ciently scattered and corroded not to put any serious obstacles 

 to the progress of our ship. East of the Beli Ostrow Island 

 we found the sea entirely free from ice». 



From a close inspection of the foUowing sections [f. ex. 

 III, VII & VIII] we learn, that almost in every place, where 

 the ships journal tells us of an encounter with the ice, there 

 is a marked tendency in the cold-wåter isotherms to rise 

 towards the surface. In the following I intend to return once 

 more to this fact. 



Petermann,- endeavouring to trace the isotherms of the 

 surface water of the Kära Sea for Jul}'' and August from the 

 Norwegian observations in 1870, stated the fact, that the 

 middle part of the sea between Novaya Zemlya and the Beli 

 Ostrow island has the lowest temperaturs and is frequently 

 covered with ice in summer. This observation bas been con- 

 firmed by every expedition of låter years. 



»Die Norwegischen Beobachtungen weisen hier fiir die 

 Monate Juli und August in den meisten Theilen des Meeres 

 eine durchschnittliche Temperatur zwischen 2° und 4° auf, 

 ganz besonders im siidwestlichen und nordöstlichen Theile, 

 dazwischen in der Mitte des Meeres zeigt sich eine Stelle 

 unter 2", in ihrer Mitte eine noch geringere, unter O'' und bis 



— 0°.8 » Es erinnert dies an den Schmelzprocess des 



Wintereises unserer Teiche auf denen zuletzt nur noch in der 

 Mitte eine Eisscheibe ilbrig bleibt.» 



^ Vega-expeditionens vetenskapliga iakttagelser, Vol. 1, page 12. 

 2 Geogr. Mittli. 1871. Die Erschliessung eines Theiles des nördl. Eis- 

 meeres, 1870. 



