Air temperatures along Baffin Island averaged 

 about normal while those along the Labrador and 

 Newfoundland coasts were much below normal 

 throughout the winter and spring, and well into 

 the summer months, as shown in figure 29. The 

 locations of the stations monitored are shown in 

 figure 27. A frost degree day, as used in figure 

 29, is defined as one day mean temperature of one 

 Fahrenheit degree below 32° (e.g., one day at 

 20°F would be 12 frost degree days). Similarly, 

 a melting degree day is one day mean tempera- 

 ture of one Fahrenheit degree above 32°. All 

 stations had a below normal frost degree day 

 accumulation at the end of December. By the 

 end of January, the Newfoundland and Labrador 

 stations had surpassed their respective normals 

 and made rapid accumulations through the early 

 spring. The melting degree accumulations for 



the remainder of spring and for the entire sum- 

 mer lagged significantly behind normal. Iceberg 

 deterioration can thus be inferred to be less than 

 normal allowing a greatly retarded mortality rate 

 among the bergs destined for the Grand Banks, 

 and an extension of the season of at about a 

 month past its normal termination in mid-July. 

 These same environmental conditions described 

 above produced a greater and more persistent sea 

 ice cover as discussed in the section on Ice Con- 

 ditions, 1974 Season. This provided protection 

 to the bergs from sea state erosion through a 

 greater portion of their journey and particularly 

 influenced the larger counts south of 48 °N lati- 

 tude in the second half of the season. Collater- 

 ally, sea surface temperatures were lower than 

 normal in the vicinity of the Grand Banks 

 throughout the season. 



12 



