the last two days of the study, 

 measurement estimates of the 

 dimensions of the iceberg were 

 made by bringing HORNBEAM 

 alongside the iceberg. The 

 estimates were made using the 

 frame numbers on the 

 HORNBEAM. Photographs of 

 the iceberg were taken and the 

 range to the iceberg and the focal 

 length of the lens recorded so 

 measurement estimates could 

 later be made from the pictures. 

 The position of the iceberg, wave 

 height and period, and wind force 

 and direction were recorded 

 hourly. SST was recorded 

 several times per day. 



The observed environmental 

 information was used as inputs 

 into HP's deterioration model 

 (Table B-4). An assumed relative 

 motion of 25 cm/s was used in 

 calculating wind force convective 

 melting. Calculated remaining 

 length was plotted against the 

 maximum observed length 

 (Figure B-9). The results show 

 the model gives fairly good 

 predictions for this one case. 



There were several major calving 

 events observed. The IIP model 

 does not include calving. El- 

 Tahan, et al. (1 984) used a time 

 integrated scheme at the iceberg 

 waterline wave-cut notch to 

 model calving. (The loss due to 

 calving is estimated to be of the 

 same order as wind driven 

 convection.) The iceberg we 

 observed showed some 

 weakness in the above scheme. 

 El-Tahan, et al. (1984) assume 

 the iceberg remains in a constant 



Figure B-8. Photographs of the iceberg observed during the drift and 

 deterioratbn portion of the 1984 International Ice Patrol cruise. 

 Top: 1426Z 16 July 1984, 115-120m across base, maximum height37m. 

 Bottom: 1400Z21 July 1984, 45-50m across base maximum height 13m. 



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