FIGURE 28. Newly formed pads of pancake sea ice a 

 few feet across as viewed from the deck of the USS 

 CURRITUCK after a few days of below-freezing weather. 



When the ship was lying to near the pack, icebergs some- 

 times appeared to be plowing through the sea ice because, 

 as is well known, bergs are usually current driven while 

 sea ice is wind driven. For this reason the bergs may move 

 at a different rate from that of the sea ice and often move in 

 a different direction. This is related to the deep draft of the 

 bergs and especially to their great mass because, relative to 

 sea ice, bergs have a small surface area for the wind to act 

 on as compared to their mass. 



During the last few days of February, the temperature, 

 which had been continuously above freezing, dropped to a 

 little below freezing and pancake ice formed. This presaged 

 the growth of the ice pack and the coming of winter. The 

 freezing of sea water is markedly different from that of fresh 

 water. Fine needles of ice form slightly below the surface 

 and then float to the surface producing a slush. After slight 

 surface buffeting and further freezing, this slush is trans- 

 formed into "lily pads" of pancake ice (see fig. 28). 



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