Tabid 1. Source of International Ice Patrol Iceberg Reports by Size. 



Percent 



Sighting Source Growler Small Mediunn Large Radar Target Total of Total 



Coast Guard SLAR 29 94 82 30 12 247 12.9 



Coast Guard Visual 40 94 85 26 245 12.8 



CanadianSLAR 2 34 23 12 245 316 16.6 



Canadian Visual 11 253 124 49 437 22.9 



Ship Radar 5 5 18 3 49 80 4.2 



Ship Visual 43 95 195 61 394 20.6 



Offshore Oillndustry 9 35 24 8 4 80 4.2 



Lighthouse/Shore 1 1 0.1 



DOD Sources 14 53 34 101 5.3 



Other 4 10 3 8 0.4 



Total 139 628 606 223 313 1909 100.0 



MP'S computer model 

 consists of a routine which 

 predicts the drift of each 

 iceberg, and a routine which 

 predicts the deterioration of 

 each iceberg. The drift predic- 

 tion program uses a historical 

 current data file to drift the 

 icebergs. This historical data 

 file is modified weekly using 

 satellite-tracked ocean drifting 

 buoy data to take into account 

 local, short-term current 

 fluctuations. Murphy and 

 Anderson (1985) describe the 

 IIP drift model in more detail, 

 along with an evaluation of the 

 model which was conducted in 

 1985. 



The IIP iceberg dete- 

 rioration program uses daily 

 wind, sea surface temperature, 

 and wave height information 

 from the U.S. Navy Fleet 

 Numerical Oceanography 

 Center to melt the icebergs. 



8 



Anderson (1983) describes the 

 IIP deterioration model in 

 detail. It is the ability of the 

 SLAR to detect icebergs in all 

 weather, and the HP's com- 

 puter models to estimate 

 iceberg drift and deterioration, 

 which has enabled IIP to reduce 

 its ICERECDET operations from 

 weekly deployments to every 

 other week deployments. 



Table 1 shows the total 

 iceberg sightings reported to 

 IIP in 1987 (including re- 

 sights), broken down by the 

 sighting source and iceberg 

 size. The number of iceberg 

 sightings shown in Table 1 are 

 only those which were in MP's 

 operations area and away from 

 the Newfoundland coast. For 

 example, more than one iceberg 

 sighting was received from the 

 Canadian lighthouses, but since 

 most were nearshore, only one 



was entered into MP's com- 

 puter model. Appendix A lists 

 all iceberg sightings received 

 from commercial shipping, re- 

 gardless of the sighting loca- 

 tion. 



The SLAR continued to 

 be an important instrument in 

 iceberg detection in 1987. IIP 

 and Canadian (AES) SLAR 

 observations accounted for 

 29.5 percent of all 1987 

 iceberg reports (Table 1). 

 Visual and SLAR observations 

 from Canadian (AES) sea ice/ 

 iceberg reconnaissance flights 

 accounted for 39.5 percent of 

 all 1987 iceberg reports. This 

 is a significant increase from 

 the past, representing greater 

 emphasis on iceberg reporting 

 by AES, and again indicating the 

 increased mutually-beneficial 

 cooperation between IIP and 

 AES. 



