ized format, three source choices were used; 

 USCG Aircraft, USCG Ship, orother. In merg- 

 ing this portion of the data set, USCG ship 

 reports were encoded as a "6" (ship reports). 

 If the iceberg description was recorded as a 

 radar target and the sighting source was an 

 USCG aircraft, the sighting source was set to 

 1 (USCG Aircraft Radar/SLAR). If the iceberg 

 description was a non-radar and the sighting 

 source was an USCG aircraft, the sighting 

 source was encoded as a 2 (USCG Aircraft 

 Visual). The "other" category could include 

 lighthouse reports, shipping reports, and re- 

 ports from commercial aviation. 



- Sighting Time. No sighting times were origi- 

 nally recorded for this portion of the data base 

 and the sighting time field was set to 0000. 



icebergs represented by the record was car- 

 ried forward unless the number was greater 

 than 20. In that case, the number of icebergs 

 for the record was questionable and the num- 

 ber was set to one. 



- Days on Plot. Set to zero. 



- Date of Last Model Position. 

 Set to xxxxxx. 



Model Season File Years Portion of the 

 Data Base 



During the early years of the model, not 

 all of the data fields were used. The below 

 comments for the data field refer to the years 

 in parenthesis following the data field: 



- Last Model Analysis Position. The iceberg 

 drift model was not in use and this position was 

 set to North West. 



- Number of Icebergs. Original sightings dur- 

 ing this period were classified in different man- 

 ners with respect to the number of icebergs 

 each sighting represented. The following code 

 was used when the data for this period was 

 computerized: 1 - Unknown, 2 - Numerous, 

 and 3 - Many. If the actual number of icebergs 

 the record represented was actually known, 

 that number was entered. This number could 

 be 1 , 2, or 3. After about the mid-1 970s, one 

 record generally represented a single iceberg. 

 When this portion of the data base was being 

 entered, the original entry for the number of 



- Iceberg Index (1982-1984). During this pe- 

 riod, a problem in the computer program logic 

 occasionally allowed a "D" to placed where a 

 "+" belonged. The error was carried forward 

 into the data base and is not considered critical 

 because of the proper use of the resight data 

 field. 



- Sighting Source (1 982-1 983). This field was 

 not used by the model during this period. In 

 creating the data base, the sighting source 

 was set to "X - Unknown" for these records. 



- Number of Icebergs (1 982-1 985). This field 

 was not used in the model during this period. 

 In creating the data base, this field was set to 

 1 for these records. 



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