Table 1. Years with the lowest number of 

 icebergs estimated to have drifted south of 

 48° N and North Atlantic Oscillation Index. 

 Note: The iceberg-count data reflects the 

 current definition of the ice year. In 1940 

 and 1941 the ice year was the calendar 

 year. In both years it was reported in HP's 

 annual reports that two icebergs passed 

 south of 48° N during the year. One of these 

 icebergs passed south of 48° N in 

 November 1940 and was originally counted 

 as a 1940 observation. It is now counted as 

 a 1941 observation. Thus, in 1940 there is 

 one iceberg listed, and in 1941, three. 



extremely light iceberg season that 

 followed. Seven of the ten lightest iceberg 

 years in Ice Patrol's record (Table 1) had a 

 strongly negative NAOI. Two years (1931 

 and 2005) had a neutral NAOI and one 

 (1952) was moderately positive. 



While Table 1 shows encouraging 

 agreement between NAOI and low iceberg- 

 count years, there are dramatic 

 inconsistencies in some years. For example, 

 in 1996 the NAOI was -3.78, the sixth 

 lowest NAOI in Hurreirs (2007) 142-year 

 record; however, 611 icebergs passed south 

 of 48°N making it a very active iceberg 

 year. As a result, comparisons between 

 NAOI and iceberg counts should be 

 interpreted with the caution that, although 

 the overall relationship is good, individual 

 years can be entirely incompatible. 



By the end of January 2006 Ice Patrol 

 recognized that 2006 was going to be 

 extraordinary. The antecedent environmental 

 conditions, pre-season surveys, and forecasts 

 collectively pointed to the likelihood of a 

 very light year. The October 2005 CIS survey 

 of the Davis Strait area (Desjardins, 2005), 

 although limited in scope, found the fewest 

 number of icebergs in the six years the 

 survey had been conducted. 



January 2006 pre-season iceberg 

 surveys by PAL and IIP showed a small 

 iceberg population along the Labrador coast, 

 which led to the anticipation that few, if any 

 icebergs, would reach the Grand Banks. 

 Finally, based on the slow early sea-ice 

 growth, Peterson's long-range iceberg 

 forecast system (Peterson, 2004) predicted 

 sparse population of icebergs throughout the 

 ice year (Peterson, personal communication). 



An ice year like 2006 renews the 

 awareness of the impressive variability of Ice 

 Patrol's iceberg counts. This appreciation is 

 not recent. Edward H. "Iceberg" Smith 

 (1926) said: "The amount of ice drifting out 

 of the north into the open Atlantic is subject 

 to great annual variations, for instance, in 

 1912 there were approximately 1,200 bergs 

 counted south of Newfoundland while in 

 1924 there were only a total of 1 1 ." 



It is remarkable that 2006, a second 

 year without icebergs, followed a year with 

 only 11. Having two consecutive years with 

 exceptionally low iceberg counts is unusual, 

 but not unprecedented. This has happened 

 three additional times in Ice Patrol's history: 

 1940-1941, 1951-1952 and 1965-1966. The 

 combined iceberg count for 1940 and 1941 

 was four. [During these two early World War 

 II years mariners were reluctant to break 

 radio silence to make iceberg reports and 

 reveal their location, so there may have been 

 isolated icebergs that were not reported. In 

 both years the USCG cutter General Greene 

 conducted oceanographic surveys of the 

 region, focusing their attention on the 

 offshore branch of the Labrador Current and 

 the southern Grand Banks. They found that 



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