116 



MAKIOiSr EXPEDITION TO DAVIS STRAIT AND BAFFIN BAY 



until equilibrium is reestablished. Then the cycle of destruction is 

 reenacted. 



Bergs which calve frequently, producing numerous growlers, 

 naturally expose a greater and greater ice surface, and therefore 

 Avaste faster than those bergs Avhich resist fracture because of their 

 particular sl^ape. or of calmer seas, or of other causes. Bergs which 

 are completely water washed present fewer overhanging prominences 

 than others, and are. therefore, less lial)le to calve. Such shaped 

 bergs exposed to the same conditions survive hmger than any other 

 kind. 



The natural |)rocesses of disintegi'ation that attack a (Treenland 

 berg when it reaches the warm ocean south of the tail of the (xrand 



An Iceberg Buffeted by Winter Gales 



Figure 75. — Bergs drifting; south of Newfoundland in early season (February to 

 March) leave pr'otective coast lines far lichind. Tlien they are subjected to a 

 severe buffeting by gales and ocean swidl which sometimes "shoot the spray hun- 

 dreds of feet in the air. Only the sniallrr-sized bergs, however, display any per- 

 ceptilile motion ; ice bodies as large as the one shown here remain as immovable 

 as a rock. This lierg measured l."i(i feet above the water and 400 feet in length. 

 (Official photograph, international ice patrol.) 



Bank are interesting to follow. Thus when one i)articiilai- her<j 

 which on April 4. 11)24. emerged from arctic surroundings of 3*2 - F.. 

 to enter mixed water of 35° F.. was then of medium size, consisting 

 of a low ridge at one end sejiarated by a shallow channel from a 

 peak approximately 125 to 150 feet high at the other. The wind 

 remained light for the next two days and the water warmed from 

 34° to 38°. while a slight swell Avashing the base of the berg ma- 

 terially assisted the melting processes. A groAvler A\'as observed to 

 calve occasionally, but disintegration Avas not rapid. By the next 

 day the temperature of the sea had risen to 40° F., and a heavy sAvell 

 makinir up about noon initiated rapid wastage. AVhen the ber^ 

 crossed the "cold wall," early the morning of the 8th, and floated in 



