ing the summer and fall the conditions are better over the inland 

 stations than over the coastal stations. But again, the poorest 

 conditions are to be found in the Kara and eastern Barents Sea 

 regions. The very short record for Franz Josef Land indicates 

 that visibility conditions are much poorer at Tikhaja Bay in the 

 south than at Rudolph Island in the extreme north. 



Limitations to visibility in the arctic region are primarily fogs, 

 blowing snow, and local smoke. The different types of fogs are 

 considered in the next section. Local smoke is serious only in 

 the vicinity of the larger towns, and often occurs with the shallow 

 radiation fogs of winter. 



Blowing snow constitutes a much more serious hazard to flying 

 in the Arctic than in more temperate latitudes. By comparison, 

 the snow is dry and consists of fine particles. It is easily picked 

 up by gentle or moderate winds and is drifted into the hollows, 

 leaving the higher elevations bare. Winds of 9 to 14 m. p. h. will 

 raise the snow a few feet off the ground, and the blowing snow 

 will obscure surface objects such as rocks and runway markers. 

 Winds of 15 m. p. h. or higher will raise the snow to consider- 



Figure 3-6. — Blowing snow. 



112 



