St. Lawrence River tlirou*;'li the ice fields and b}- 25 Apiil there was 

 open water from Cabot Strait to Montreal. The passage between 

 Sable Island and Cape Breton remained endangered by sea ice until 

 mid-April when the ice receded northward. The southern portion 

 of the Gulf and the coast of Cape Breton remained clogged with 

 extremely heavy pack ice. 



Figures 4 and 5 indicate the temperature distribution as reported 

 during the month of April. The 30° isotherm gives an excellent 

 indication of the retreat of the sea ice. The 32° isotherm shows the 

 lack of activity of the eastern branch of the Labrador Current. 



Figure 12 sunnnarizes the icel)ergs and growlers reported during 



the month south of 49° X. The one berg located east of 46° W. was 



reported on 14 April. However, an observation flight on the same 



(hiy and hi the same area failed to disclose its presence. As numerous 



fisiiing vessels were in the area, it is believed that the reported berg 



was actually another vessel. Tlie figure also shows the sea ice limits 



on 30 April. 



MAY 



During the first week in May the wind swung from northeast to 

 east to southeast aufl brouglit rapid clumges to the ice conditions. 

 The large field of pack ice split apart just south of Cape St. Mary 

 leaving one field stretching from 45°45' X. to 47° X\, and from 

 54°10' W. to 55°50' W., while tlie other field extended from 46° X. 

 at 53°50' W., northward along the east coast of Xewfoundland. The 

 split of the ice fields allowed for rapid disintegration of the ice, 

 especially during the second week wlien the wind swung to the south- 

 west bringing warm surface winds and causing a rise in the surface 

 water temperature. This is clearly seen by comparing the two 

 isotherm charts for the month of May. By the end of May, the 

 32° surface water had completely disappeared. The western field 

 shifted rapidly into Placentia Bay and there disintegrated. The ice 

 along the east coast of X^ewfoundland also disintegrated rapidly. 

 First it was forced offshore and the surface temperature and slight 

 wave action caused rapid melting. By 20 May, there was no sea 

 ice south of Cape Bonavista and by 31 May there was none south 

 of Belle Tsle except for a few trapped flows in Xotre Dame and White 

 Bays. In 20 days, the southern linnt of sea ice had retreated over 

 360 miles. 



The advent of the southerly winds and the breakup of sea ice soon 

 brought about a major change in the iceberg distribution. The 

 southermost bergs rapidly disintegrated under the combined forces of 

 heat and wave action, while the remainder south of the Avalon Penin- 

 sula drifted towards shore into the bays and shallows. During the 

 month, a total of six bergs came south of 48° X". of which two drifted 

 past Cape Spear and tlie remainde.r drifted into Conception Bay. In 

 the X^otre Dame Bay area, the large number of bergs that had drifted 



