Appendix E 

 Iceberg Deterioration Estimates: A Model Comparison 



l/C Morgan Barbieri (U.S. Coast Guard Academy)* 

 LT Scott Stoermer (International Ice Patrol) 



Introduction 



To minimize the risk of iceberg collision, the U.S. Coast Guard International Ice Patrol 

 began routine patrols in 1913 after the sinking of the RMS Titanic in 1912. Ice Patrol was tasked 

 with observing and studying the ice and oceanographic conditions in the vicinity of the Grand 

 Banks and providing warnings to mariners of existing iceberg hazards. In order to create iceberg 

 warnings and accurately predict iceberg positions. IIP needs information about an iceberg's 

 characteristics (i.e., position, size, and shape), as well as environmental data, such as sea surface 

 temperature, wave height and wave period. Iceberg data is gathered from Coast Guard 

 surveillance flights, other aircraft, and ships operating in the area, while the U.S. Navy's Fleet 

 Numerical Meteorology and Oceanography Center provides environmental data. 



Personnel at the IIP Operations Center in Groton, CT use a computer model to predict the 

 drift and deterioration of icebergs based on assimilated iceberg information. Ice Patrol then 

 broadcasts the Limit of All Known Ice (LAKI) south of 52° North in message bulletins and 

 graphical charts. These messages are sent out twice per day during the iceberg season, which 

 usually extends from March to July. Ice Patrol bulletins contain the estimated LAKI and other 

 pertinent ice information. 



Iceberg modeling, including drift and deterioration estimates, is of premier importance to 

 the Ice Patrol. Since most icebergs are visually observed only once, IIP relies on the information 

 provided by computer models so that information about iceberg location can be continuously 

 provided to the mariner. In general, the iceberg model fills the gap between reconnaissance 

 sorties — which provide real-time iceberg data to update the model — with estimations of iceberg 

 locations and melt. In recent Ice Patrol history, a succession of computer models has been applied 

 to the problem of drift and deterioration estimates. The analysis presented in this paper compares 

 the melt modules of two Ice Patrol models, one presently operational and the other being 

 considered for use as its replacement. 



Background 



Attempts at modeling icebergs began in the 1960s, when IIP maintained hand plots of 

 predicted motion using vector addition of the effects of winds and ocean current. The hand- 

 plotting technique was made possible by research that IIP conducted on the effects of wind and 



• This project was conducted as a 3-credit directed-study course in coordination with the Marine 

 and Environmental Sciences Department of the U.S. Coast Guard Academy. 



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