Snow cover is irregular. Older ice may have 8 or more inches of 

 snow, while new ice may have a few inches, or be snow free* 



The northern sector of the Baffin Bay Pack is more stable than the 

 section to the south. Large expanses of the pack remain relatively immo- 

 bile for extended periods. This is particularly true of the central, 

 eastern, and northeastern portions where large expanses grow uninterrupted. 

 Exceptions are found in the north, in the reaches of the North Open Water, 

 and in the west where changes in the ice occur with regularity. 



From January to April, the region of the pack's greatest stability 

 is composed principally of medium and giant floes and fields. The ice is 

 interspersed with pressure ridges 8 to 12 feet in height. Large areas of 

 relatively flat ice separate these ridges. Small ridges, ranging in 

 height from 1 to 2 feet usually are present in varying concentrations 

 within the flat ice. Relatively few bergs are found in this ice. 



In January floes formed in the autumn may attain a thickness of 3 

 feet j it may increase to 3 to 5 feet by March and April. Snow cover gen- 

 erally is 6 to 8 inches with drifts of 12 to 18 inches. 



To the west, the pack ice that drifts along the fast ice has greater 

 mobility and contains ice of varied types; polar ice, ice formed in 

 Lancaster Sound, and that which has formed or drifted into the North Open 

 Water. Glacier ice also is found in a larger proportion. Most of the 

 ice found along the Baffin Island ice is composed of medium and giant 

 floes and fields. Its surface is rougher and has more pressure ridges 

 than that to the east. East of Pond Inlet and Bylot Island, pressure 

 ridges have been observed to exceed 15 feet in height. 



The ice is comparable in thickness, to that previously described 

 except in isolated areas that contain ice from Lancaster Sound or the 

 North Open Water. 



The ice usually is disturbed in the pack east of Cape Byam Martin and 

 for 50 or 60 miles eastward of the Lancaster Sound egress. Here, unlike 

 the central pack, the ice is in a state of greater mobility and changing 

 concentration and composition. Leads appear to open readily and close 

 before any appreciable growth of new ice takes place. Here, too, is often 

 found ice which at one time was subjected to great pressure, producing 

 ridges exceeding 15 feet in height, or floes that were compressed and 

 crushed into masses of ice with rough surfaces. 



The ice of the North Open Water is seldom stable in character; it 

 never attains great thickness because of frequent breakup. Winds, light 

 or strong, tend to clear great areas of this water and form polynyas which 

 soon acquire a cover of frazil crystals and young ice. 



The destruction of the Baffin Bay Pack occurs along its entire periphery, 

 except for the ice which remains on the coast of Baffin Island. In June, 



14 



