ERTS-A imagery has limited International Ice 

 Patrol application due to: 



(1) Resolution — advertised resolution of about 

 100m is not fine enough to identify an iceberg 

 that would normally reach the Ice Patrol area. 

 Icebergs possessing surface areas greater than 

 400m 2 constitute 65% of the total iceberg popula- 

 tion. Icebergs with surface areas of 1000m 2 com- 

 prise less than 25% of the population. The 

 0.01W resolution of the ERTS-A provides 

 identification of less than 1% of the icebergs of 

 interest to the Ice Patrol. 



(2) Cloud cover — the cloud/fog blanket nor- 

 mally present on the Grand Banks during several 

 months of the Ice Season does not allow penetra- 

 tion by ERTS-A sensors. ERTS-B carries the 

 same instrument package as ERTS-A. ERTS-C, 

 tentatively scheduled for launch in CY-78, will 

 have a MSS band 5 which will be in the near- 

 infrared range. 



(3) Frequency of area coverage — the same area 

 is covered every 18 days, though at a latitude of 

 of 40° image overlap is approximately 34.1%, 

 50° is 44.8%, and 60° is 57%. (Data Users 

 Handbook) The frequency of coverage does not 

 allow for the continuous monitoring of icebergs 

 and their drift — a requirement for Ice Patrol 

 utilization. 



(4) User availability— Wiesnet (et ah 1974) 

 states ERTS-A data is not suitable for immediate 

 forecasting due to the great time lag in the user 

 receiving the information. There is usually a 3 

 week delay from the time GSFC receives the 

 imagery till the user receives it. Ice Patrol found 

 this to be the case also. 



Though ERTS holds no present promise for 

 iceberg detection and tracking, Commander, In- 



ternational Ice Patrol is closely following satel- 

 lite development and application for possible 

 future utilization. 



Other satellite imagery has been reviewed in 

 the past by Ice Patrol, among these are the 

 ESSA series, NIMBUS series, NOAA series, and 

 the SMS/GEOS satellite. All are meteorolog- 

 ical satellites with 1km resolution. The Ice 

 Patrol utilizes the meteorological satellites for 

 weather information for flight planning and for 

 the sea ice edge. The GEOS satellite also has 

 the capability for taking radiance temperature 

 measurement. (VAETH, 1972) Though this has 

 not at present been utilized by the Ice Patrol, 

 future planning has this under consideration. 



In CY 1978, NASA intends to launch SEA- 

 SAT-A (Sea Satellite). The objectives of SEA- 

 SAT are to demonstrate a capability to measure 

 global ocean dynamics and physical character- 

 istics, provide data for user applications, and to 

 provide these data real-time to users. The Coast 

 Guard is closely following this project. SEA- 

 SAT potentially offers— (1) 36-hour repeat 

 coverage globally; (2) data dissemination in near 

 real-time (less than three hours delay adver- 

 tised) ; (3) one of the sensors, the Synthetic 

 Aperature Coherent Imaging Radar, will provide 

 all-weather images with resolution approaching 

 25 meters; (4) another of its four senor systems, 

 the Compressed Pulse Precision Radar Altimeter, 

 will determine the topography of the sea surface 

 which in turn will be related to current deter- 

 minations. (SEASAT-A Program Plan and 

 Definition) 



Hopefully, SEASAT-A's promised potential 

 will find utilization by the International Ice 

 Patrol. 



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