Type III, Baffin Bay west-east transect, Point 7-9. 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
he percen- The southern boundary of the North Water is not defined as well as the northern 
one (fast-ice boundary in Smith Sound). The west-east Baffin Bay profile coin- 
cides approximately with the southern boundary. On Dec.2,1980, there was mainly 
arefore, lose pack ice along this line with a high percentage of thin ice, the ice in the 
vast of | southern Baffin Bay not having consolidated yet. On all other flights, the per- 
inner centage of young ice was small compared with the east-west Baffin Bay profile 
nd in |  (P.18-19) some 2-300 km further north. The general situation at the southern 
nperatures boundary of the polynya is that the southward movement of the ice is hindered, 
orth and leading to a close pack ice cover. 
profiles Type III, Lancaster Sound and Barrow Strait, Point 4-7. 
infor- The ice condition in the Parry Channel depends on the location of the fast-ice 
enon” |  boundary.In Winter 1980/81 the fast-ice boundary was located in the Barrow Str. 
red on the | between Griffith Isl. and Somerset Isl. from the beginning of December (freeze 
t (Jan. | up) until February 7 and between that date and February 21 the ice in Barrow 
ter. On | Strait became landfast up to Maxwell Bay-Prince Leopold Isl. (Lancaster Sound). 
15] area, After February 21, the fast-ice boundary was again located at the same position 
e sensing as during December and January. In mid-March,the ice in Barrow Strait became 
landfast with the fast-ice boundary again at Maxwell Bay-Price Leopold Isl. From 
that date onward, the fast ice remained in Barrow Strait until break up in the 
the coas- last week of June. | 
C. On the The young ice percentage in Barrow Strait and Lancaster Sound was in 
the order of 1 to 5 with higher figures during the first flight. Because of the 
narrow channel (60 km in width), pack-ice movement is limited by its coastal 
atballla- | boundaries and by the close pack ice at the entrance into the Baffin Bay. There- 
the pa- fore young ice is observed only in fractures of different sizes with a general 
y, open orientation across the channel. A procedure was developed to calculate fracture 
flights amount and width from thermal measurements. It takes into account not only frac- 
, strong | tures associated with open water but all fractures covered by ice with a thick- 
“~The | ness up to 50 cm. The ground resolution for the infrared thermometry is esti- 
varied | mated at about twenty meters for this fracture study. Along the Lancaster Sound 
the ice profile, fracture amount and width were calculated for all six flights (Tab.3). 
ther words, | 
four days Table 3: Total occurrence frequency 04 100 Figure 6: Occurrence 
These fractunes and fracture width in per- - frequency of fractures 
File of | | centage of the amount, (o^ % Î versus fracture width 
SAX profile measurements in PE. gon the Lancaster 
£he Lancaster Sound Sound, Winter 
sb 1980/81 
an in the 3 1 
ity of the FLIGHT RS1 RS2 RS3 RS4 RS5 RS6 = 
DATE Dec.2 Dec.20 | Dec.29 | Jan.22 | Feb.7 March.2 | Mean oe > t 
Total 1980 1980 1980 1981 1981 1981 : 3 s. 
: Fractures 117 140 266 178 117 80 150 : a o 
o Baffin 20-200 m 58 64 66 62 63 58 62 ak : = : o o 
tie 200-400 m 22 24 20 25 24 21 23 f à 
r (Tab.2). 400-600 m 9 9 9 7 9 5 8 3 x 
f Coburg 600-800 m 6 1 3 3 3 4 3 x NS. 
tance of 800-1000m 2 1 1 l 0 5 2 2F mean value o 
easured. euet ^ > : 1 0 4 2 facte fMi. om 
ce-free > 1200m 1 0 2 2 i 7 2 L l l A 4 
0.2-2 2-4 4-6 6-8 8-10 
775 
cá 2^, A T MIN Re NN RE. De red re SRR ERO Mna 
Ra eR. e NOU NUN e A Du e BEER |