only a general distinction was made between growlers and icebergs. By the mid- 1 920' s, small, 

 medium, large and very large icebergs were listed, but no specific measurements were recorded. It 

 is likely that there were specific definitions for each of the various size classes at that time, but 

 they were not recorded in the reports. It is also reasonable to assume that the definitions were 

 listed in feet and originated with those that Murray used in 1968. It is clear from Murrayf 1968) 

 and Osmer( 1974) that IIP has long distinguished between tabular and non-tabular icebergs. 



Sometime after 1976, IIP decided to define a single size classification based on the earlier 

 size characteristics of a non-tabular iceberg. These also appear to be based on the sizes given by 

 Murray! 1968). When IIP and the Canadian Ice Service (CIS) cooperated to develop the MANICE 

 code in the mid-1980's, the definitions of the size classes were expressed solely in meters, and 

 rounded to the nearest ten meters for simplicity. 



The degree of uncertainty in iceberg size observations vastly exceeds the minor 

 differences between the MANICE and legacy IIP iceberg sizes. There is no sensor or detection 

 method available to us today that is capable of making a measurement of that resolution. 

 Accordingly, beginning with the 2007 ice season, IIP will adopt the MANICE code 

 classifications, as presented in Table 2. 



References 



Anderson, I. (1983). Iceberg Deterioration Model. Appendix C to Report of the International Ice 

 Patrol in the North Atlantic Ocean. Bulletin No. 69. 



Canadian Ice Service. (2002). Manual of Standard Procedures for Observing and Reporting Ice 

 Conditions (MANICE), 9 th Edition. 



Iceberg Size Classification. (2007). Retrieved March 7th 2007 from: 

 http://www.uscg.mil/lantarea/iip/FAQ/Icebergs 5.shtml 



International Ice Patrol. (1914-1983). Report of the International Ice Patrol Service in the North 

 Atlantic Ocean. 



Murray, J.E. (1968). The Drift. Deterioration and Distribution of Icebergs in the North Atlantic 

 Ocean; Ice Seminar: A conference convened by the Petroleum Society of CIM, Calgary, 

 Alberta, May 1968. 



Rodman, H. (1890). Ice and Ice Movements in the North Atlantic Ocean. U.S. Navy Hydrography 

 Report 1890. 



The author wishes to acknowledge the following people for their assistance: 



Dr. Donald Murray. International Ice Patrol 



Mrs. Claudette Cloutier, Manager, Gallagher Library 



Mrs. Ellen Levy, Librarian, Woods Hole Oceanographic Institution 



52 



