". 



. .-, ' 



. 



,. 





Figure 13 Composite buoy tracks. Blue stars represent drop locations of air-deployed buoys. Red stars 

 represent ship-deployed buoys. 



satellite-tracked drifting buoys. The AXBT 

 probes measured the water-temperature profile, 

 which helped Ice Patrol determine the location 

 of the Labrador Current, validate temperatures 

 from satellite-tracked drifting buoys, and obtain 

 precise sea-surface temperatures for numerical 

 models. 



After coding AXBT data into a standard 

 format, Ice Patrol shared it with the Canadian 

 Maritime Atlantic Command Meteorological 

 and Oceanographic Center — HP's supplier of 

 AXBT probes— and the U. S. Naval Fleet 

 Numerical Meteorological and Oceanographic 

 Center, where it was quality controlled and 

 redistributed via oceanographic products. 



A change in AXBT drop policy in 2002 

 led to a dramatic decrease in the number of 



AXBT drops in subsequent years. The policy 

 requires that the patrol aircraft have visibility of 

 the ocean surface before deploying AXBTs and 

 that drops not interfere with reconnaissance. 

 The frequent poor visibility on the Grand 

 Banks therefore restricts HP's ability to deploy 

 AXBTs. For this reason, the policy is under 

 review. 



Satellite-tracked drifting WOCE buoys, 

 drogucd at a depth of fifteen or fifty meters, 

 provided near real-time ocean-current 

 information. Ice Patrol deployed WOCE buoys 

 on the Grand Banks and in the offshore and 

 inshore branches of the Labrador Current and 

 used data from these buoys to modify the 

 historical-current database within HP's 

 computer model. 



11 



