DISTRIBUTION OF ICE IN BAFFIN BAY AND DAVIS STRAIT 



A. INTRODUCTION 



A description of sea ice conditions in Baffin Bay and Davis Strait 

 would be incomplete without a brief discussion of the general disposi- 

 tion of the water circulation, and some of the external forces to which 

 they are exposed. Movement and structural peculiarities of the ice are 

 due chiefly to the geographical position of these waters and their 

 circulation. 



The Baffin Bay-Davis Strait system of waters is complex,. Currents 

 off the southwestern coast of Greenland, characterized by relatively 

 high salinities and temperatures, flow northward into the waters' off 

 Disko and beyond. Tributary waters from Lancaster, Jones, and Smith 

 Sounds flow into northwestern Baffin Bay. From here the currents travel 

 southward along the coasts of Baffin Island and Labrador bringing in 

 polar waters. A great eddy-current system is formed in Baffin Bay, To 

 the south, the warm north-setting, West Greenland Current is diverted by 

 the Hellefiske Bank and the Davis Strait ridge to the west, and south 

 toward the coast of Labrador and back into the Labrador Sea. Thus, slow 

 warm waters set against swift cold waters markedly influencing the forma- 

 tion of ice in the area. 



The first area of the striking effect of the influence of the warn 

 currents is the Labrador Sea and along the shores of western Greenland as 

 far north as the southern approaches to Melville Bugt. South of the 66th 

 parallel, except for a few coastal indentations and fjords, the waters 

 rarely freeze. To the north of this latitude, except for the fjords and 

 bays, the ice arrives late, is generally weak, and is very unstable. The 

 westward and southward deflections of the large water mass by the Hellefiske 

 Bank not only keeps the inner waters of the Labrador Sea free of sea ice, 

 but also causes large quantities of sea ice at th© southern periphery of 

 the Baffin Bay-Davis Strait pack to drift southwest ward, thereby contrib- 

 uting to the great ice drift off the Labrador coast. 



The second region where water circulation influences the behavior of 

 ice is the western part of Baffin Bay and Davis Strait from the area of 

 southern Ellesmere Island to 'Newfoundland. Here the cold currents exert 

 constant pressure on the ice, setting some sections of the Baffin Bay Pack 

 into eddy motions, and carrying large quantities of sea ice formed in 

 Baffin Bay and Davis Strait southward into the drift stream off Labrador. 

 Winter and polar ice discharged into Baffin Bay through the sounds enter 

 th» pack, become part of it, and are carried southward. Disturbed sections 

 of the pack expose areas of water which rapidly refreeze, only to break 

 again and resume the production of new winter ice. It grows and replen- 

 ishes the great drift of Ice to the south in this manner. 



Tide affects the ice in these regions. In areas of large tide ranges, 

 ice is pil^d against the shor°. This is noted in the early stages of ice 

 formation and growth. At pbb tide, slush packed against the shore is 



