HOW DO THE LABRADOR AND GULF STREAM CURRENTS AFFECT ICEBERGS IN THE NORTH ATLANTIC OCEAN
After icebergs calve from the glaciers in West Greenland, they usually drift northward into Baffin Bay (See map below). Eventually, they turn to the south and move along the Baffin Island coast. They continue their southward journey in the cold waters of the Labrador Current, which carries them toward the transatlantic shipping lanes near the Grand Banks of Newfoundland. Near Newfoundland, there are two branches of the Labrador Current: the inshore branch and the offshore branch.
The inshore branch flows southward near Newfoundland's east coast, passing very close to St, John's. In some years it carries many icebergs, which creates excellent opportunities to see icebergs from shore. When the icebergs pass Cape Race, the southeastern-most point of Newfoundland, they usually turn to the west and move south of Newfoundland. Icebergs travelling in the inshore branch rarely pass south of 45ï¿½N.
The offshore branch, the more powerful of the two branches of the Labrador Current, flows southward along the eastern edge of the Grand Banks. It moves icebergs toward the much warmer waters of the Gulf Stream and its eddies. South of the Grand Banks, the surface water temperature of the can range from near freezing (about -1.7ï¿½C) in the Labrador Current to 20ï¿½C or more in the Gulf Stream. The cold waters of the Labrador Current commonly support icebergs as far south as 41ï¿½N latitude. When icebergs encounter the warm temperatures in the vicinity of the Gulf Stream, they usually melt very rapidly.
Some icebergs survive long enough to travel extraordinary distances to the south. In 1926, the southernmost iceberg observation ever recorded in the North Atlantic was located at 30ï¿½-20' N, 62ï¿½-32' W (about 150 nm from Bermuda). In addition, icebergs have also been known to travel as far east as the Azores.
The circulation in the area where the Labrador Current and Gulf Stream meet is one of the most complex and variable regions in the world; therefore, the average paths shown in the above figure cannot be used to predict iceberg movement. The U.S. Navy provides an analysis of the ocean features in the northwest Atlantic Ocean. It shows the complexity of the region where the Labrador Current and the Gulf Stream meet.
The image above shows the interaction between the Labrador Current and the Gulf Stream. Click for the latest Gulf Stream analysis. The Labrador Current has been colored blue; the Gulf Stream is red; and land is green. The limits of all known ice for that day are shown in bold black.
Ice Patrol monitors the ocean currents in this area using drifting buoys (see FAQ #2 under IIP Oceanography)