number of icebergs crossing this parallel serves as a clue for IIP to establish a LAKI and initiate 

 daily warnings. 



Using this measure, Murphy (1999) presented a historical context for the extraordinarily 

 light 1999 season by examining the 10 lightest seasons on record. 4 This report provides an 

 excellent basis on which to examine the information available to and the decisions made by prior 

 Ice Patrol Commanders faced with small iceberg populations. Table 1, adapted from Murphy 

 (1999), includes the 2005 season. Because Ice Patrol began using aerial reconnaissance after 

 World War II, it is useful to discuss progress in ice observation and LAKI dissemination by 

 examining pre- and post-World War II seasons separately. 



P re-World War II : During pre- World War II 

 seasons (1941 and earlier), considerable effort was 

 required both to monitor ice conditions and 

 disseminate iceberg information to passing steamships. 

 The first light ice year of 1924 took the Coast Guard 

 by surprise. Not knowing exactly how to approach a 

 light season, Ice Patrol leadership took a busincss-as- 

 usual approach. As such, U.S. Coast Guard cutters 

 Tampa, Modoc, and Ossipee scouted for ice almost 

 continuously despite the small number of icebergs ( 1 1 

 south of 48°N). 



Reduced iceberg activity during this season 

 allowed the IIP Commander (Tampa's commanding 

 officer) to make observations and informal 

 investigations of the environmental causes of this light 

 ice year. Early Ice Patrol records clearly show the 

 tremendous emphasis placed on occanographic study. ~ Knowledge of the iceberg environment 

 remains essential to determining when to establish and disseminate the LAKI. In fact, rigorous 

 study constitutes a key component of monitoring iceberg danger and is critical in effectively 

 "guarding" the LAKI. 



In addition to systematic study of the ocean by ship, Ice Patrol personnel sought the 

 wisdom of native Newfoundlanders to learn about local indicators of expected ice-season 

 severity. LCDR Edward "Iceberg" Smith said that the purpose of a port call at St. John's, 

 Newfoundland, in May of 1924 was "to interview local mariners regarding ice conditions in the 

 vicinity of Newfoundland." 1 After departing St. John's, the ice-patrol vessel continued 

 northwest, interviewing observers at Belle Isle, Newfoundland, and Battle Harbor, Labrador. (See 

 Figure 2 for geographic references.) These observers attested to the unusually light extent of 

 pack ice and noted the tremendous contrast between the 1924 early March seal hunt near the 

 shores of White Bay, Newfoundland, and the 1923 hunt (approximately 350 nautical miles to the 

 southeast). Smith later commented in the 1940 annual report that results of the seal-fleet catch 

 actually showed short-range iceberg-forecasting promise since news from the seal fleet preceded 

 realization of a light iceberg year by about one month. 8 



During the 1931 season, when only 14 icebergs drifted into the shipping lanes, cutters 

 Pontchartrain and Mojave remained on call for ice-patrol duty, while the occanographic vessel 

 General Greene conducted extensive occanographic sampling. In addition to these scientific 

 duties, General Greene performed double duty by acting as a sentinel to warn shipping of 

 impending iceberg threats and to transmit ice broadcasts as scheduled. The 1931 annual report 

 also includes results from an expedition that sent "Iceberg" Smith to the Graf Zeppelin for an ice 



Table 1. Years with the lowest number of 

 icebergs estimated to have drifted south of 



48"N 



48 



