PLATE IX. Ross Ice Pack, December 1956. USS ATKA transits 

 ice pack in convoy with other icebreaker and cargo vessels. 

 Note shape of floes and raised floe edges caused by ice 

 motion during storm periods. 



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PLATE X. Ice conditions, McMurdo Sound, December 1956. Note ice 

 broken out by icebreakers to provide mooring places for cargo 

 vessels, unbroken bay ice shorefast to Ross Island in background. 



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