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 |