Sightings of targets outside HP's Area of Re- 

 sponsibility (AOR) were not entered into the 

 model. Most of these were far to the north of 

 MP's AOR in areas not covered by MP's model. 

 Coastal iceberg sightings were also screened, 

 and only those with the potential to drift into the 

 transatlantic shipping lanes were entered into 

 the IIP model. 



Table 3 includes icebergs detected 

 south of 48°N plus the number of icebergs 

 which were predicted to drift across 48°N for 

 each month of 1 994 . During the 1 994 ice year, 

 an estimated 1765 icebergs drifted south of 

 48°N; whereas, during 1993, 1753 icebergs 

 had drifted south of 48°N. 



Table 3 

 Number of Icebergs South of 48°N 



~^ 



Total 



1765 



t; 



IIP classifies the severity of the ice 

 seasons based on the historic iceberg counts 

 of its entire 80 year history. Ice years with 

 fewer than 300 icebergs crossing 48°N are 

 defined as light ice years; those with 300 to 

 600 crossing 48°N as moderate; and those 

 with more than 600 crossing 48°N as extreme 

 (Appendix C). 1 994 was an extreme year for 

 iceberg conditions. 



The 1994 season was the second year 

 that IIP used its iceberg Data Management 

 and Prediction System (DMPS). This system, 

 which is nearly identical to the iceBerg Analy- 

 sis and Prediction System (BAPS) used at the 

 Canadian Ice Centre, Ottawa, combines an 

 iceberg drift model with a deterioration model. 

 The model uses wind, ocean current, and 

 iceberg size data to predict the movement and 

 deterioration of all icebergs entered into DMPS. 

 The drift prediction model uses a historical 

 current data base which is modified weekly 

 using satellite-tracked ocean drifting buoy data, 

 thus taking into account local, short-term, cur- 

 rent fluctuations. MurphyandAnderson(1985) 

 described and evaluated the drift model. 



The iceberg deterioration model uses 

 daily seasurfacetemperature and wave height 

 information from the U.S. Navy Fleet Numeri- 

 cal Meteorological and Oceanography Center 

 (FNMOC) to predict the melt of icebergs. 

 Anderson (1 983) and Hanson (1 987) described 

 the IIP deterioration model in detail. 



Twelve satellite-tracked ocean drifting 

 buoys were deployed to provide current data 

 for HP's iceberg drift model during the 1994 

 season. The buoys are similar in design to the 

 World Ocean Circulation Experiment (WOCE) 

 and were equipped with surface temperature 

 sensors and a drogue centered at 50 meters. 

 Drift data from the buoys are discussed in the 

 IIP 1 994 Drifting Buoy Atlas, which is available 

 upon request. 



