Appendix B 



International Ice Patrol's 1988 Drifting Buoy Program 



INTRODUCTION 



The 1988 iceberg season was the 

 thirteenth consecutive year that 

 the International Ice Patrol (IIP) 

 has used satellite-tracked buoys to 

 measure currents in its operations 

 area in the western North Atlantic 

 Ocean. The buoy trajectories are 

 used to provide near realtime 

 current data to the Ice Patrol 

 iceberg drift model. These 

 currents are used to modify the 

 mean currents temporarily in the 

 region through which the buoy is 

 moving. Shortly after a buoy 

 departs the region, the current 

 reverts to its mean value. 



During 1988 Ice Patrol deployed 

 eleven buoys, six for operational 

 use and five as part of an evalu- 

 ation of a new buoy type. Of the 

 six operational buoys, five pro- 

 vided excellent data. One buoy 

 failed on deployment. 



The 1988 drifting buoy program 

 was unique in two ways. First, it 

 marked the first time that all of the 

 operational buoys were recovered 

 and returned to Ice Patrol at the 

 conclusion of the season. Sec- 

 ond, it was the first time that Ice 

 Patrol deployed mini-drifting buoys 

 during its season. In all, Ice Patrol 

 reconnaissance aircraft deployed 

 five mini-drifters, four in coopera- 

 tion with the U.S. Navy and one 

 with the Canadian Atmospheric 

 Environment Service (AES). 



The standard configuration for the 

 operational buoys is a 3 meter 

 long spar hull with a 1 meter 

 diameter flotation collar. Each 

 buoy was equipped with a 2 by 10 

 meter window-shade drogue 

 attached to the buoy with a 50 

 meter tether of 1/2" (1.3 cm) 

 nylon. The center of the drogue 

 was at a nominal depth of 58 m. 

 In addition, each buoy had a 



Donald L. Murphy 



temperature sensor mounted 

 approximately 1 m below the 

 waterline, a drogue tension 

 monitor, and a battery voltage 

 monitor. The sea surface tem- 

 perature is accurate to approxi- 

 mately 1°C. 



The data from the buoys are 

 acquired and processed by 

 Service ARGOS. Ice Patrol 

 queries the ARGOS data files and 

 stores the buoy data once daily. 

 Most of the buoy position data fall 

 within the standard accuracy 

 provided by Service ARGOS 

 (-350 m). All of the buoy data 

 were entered onto the Global 

 Telecommunications System 

 (GTS). Each buoy is assigned a 

 World Meteorological Organization 

 (WMO) number. 



Table B-1 summarizes the 1988 

 buoy deployments. 



Table B- 1. Summary of 1988 Deployments. 



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