FOHEWDRD 



In recent years the growth of Arctic operations has brought an 

 increased concentration of effort directed at facilitating ship 

 movements in the Arctic basin* This report sximmarizes the latest 

 information about the nature of the Polar Pack, its age and volume, 

 and provides aids in forecasting changes in the ice from the opera* 

 tional point of view* 



The Hydrographic Office is engaged in developing techniques of 

 forecasting ice conditions in all the waters where ice is present* 

 Since this report is tentative and much of the information is based 

 on little data, it is requested that activities receiving this pub- 

 lication fon/ard their comments to the Hydrographic Office* 



J„ B. COCHRAN 

 Captain, U*S* Navy 

 Hydi'ographer 



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