The total amount of fractures varied between 80 and 266. The fractures
were divided into seven groups according to their width. Their percentages are
also given in Tab.3. On all flights over 50% of the fractures were between 20
and 200 m in width. About 20% of the fractures were between 200 and 400 m and
about 9% between 400 and 600 m. The percentages of the different fracture groups
seem to be fairly constant for the six flight missions. The relation between the
percentage of the occurrence frequency of fractures and the fracture width is
logarithmic as shown in Fig. 6.
CONCLUSION
The North Water consists of three seperate polynyas -the Smith Sound
Polynya, the Lady Ann Strait Polynya and the Parry Channel Polynya in Lancaster
Sound or Barrow Strait, depending on the location of the fast-ice boundary. The
Smith Sound Polynya accounts for the lose pack ice in the northern Baffin Bay.
The "warm water phenomenon", measured at Cape Alexander, around Wolstenholm Isl.
and in Lady Ann Strait may be another driving force,beside strong winds and the
mechanical stability of the fast-ice boundary, for the sea ice anomaly of the
North Water.
ACKNOWLEDGEMENT
The financial support of the work was provided by Petro Canada LDT.
The author is much indebted to Professor Dr. D. Steiner and to Dr. A. Ohmura
for scientific discussions and valuable advice during the preparation of the
manuscript.and to K. Schroff for the help in the preparation of the field
work. A generous logistic support was provided by Polar Continental Shelf Pro-
ject of Dept. of Energy, Mines and Resources of Canada through its director
Dr. G.D. Hobson.
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