SCIENTIFIC RESULTS 



ir 



wai-ni water of 56° F,, it began to dwindle fast, calvin<r and rolling; 

 continuously. The swell subsided somewhat in the afternoon, but 

 the tro])ical water combined witii a moderate butfetin<r caused calv- 

 in<; to continue. The most rai)itl disinteirration took place on April 

 10; loud crackings were then continually heard, and the retreat of 

 each wave exposed a surface appearing blistered, Avith the next wave 

 crashing away the loosened covering, to be followed by another 

 draining and more blistering. During this stage the wind was light 

 southerly, a moderate southerly swell was running, and passing rain 

 squalls were experienced, typical of Gulf Stream weather. It was 

 apparent by nightfall that the effects of Avarm air, the warm waters, 

 the rain showers, and the constant pounding of the seas would shortly 

 complete the destruction of the berg, now rather small. It was not 

 surprising, therefore, next morning that we found no traces of it. 



Rapid Wastage of Icebergs in Oceanic Surroundings 



FiuuKK 70. — The rapid i-ate of disintegration of this berg can be read in the excessive 

 turbulence of the surrounding " white water."' The seas in surging through the 

 mid section have left the earth vein remaining only in the two side walls. A berg 

 as small as this one — 40 feet by 150 feet — reacts to the motion, riding the swells 

 likf a ship. (Photograph by Lieut. Commander N. G. Rickctts.) 



The rate of Avastage of about 30 feet of height per day is one of the 

 most rapid ones on record. 



From the foregoing and from other similar observations it is 

 clear that the rapidity Avith Avhich a berg that has drifted out of 

 Davis Strait and reached North Atlantic Avaters around XeAvfound- 

 land disintegrates depends upon the temperature of the air and 

 water and on the state of the sea. A berg Avhich drifts soutliAvard 

 along the east side of the Grand Bank, except late in season, is sur- 

 rounded by Avater of a temperature loAver than 35° F. (2° C.) until 

 after it passes the Tail of the Bank. Such cold surface layers are 

 primarily due to winter chilling further north, but they are partly 

 due to the presence of pack ice Avhich assists to keep the surrounding 

 water frigid and thereby allow the bergs to penetrate farther south. 

 Disintegration under such conditions is rather sIoav, but in the mixed 

 Avaters and in the Gulf Stream south of the Grand Bank it is accel- 

 erated. At 36° melting it quite noticeable: at 50° the changes can be 



