Winter operations, 1970-1971 / John C. Ayers, Norbert W. O'Hara, William L. Yocum.

Fig. 26(118).
Fig. 27(126).
Fig. 28(127).
Fig. 29(129).
Fig. 30(130).
Fig. 31(131).
Fig. 32(137).
Fig. 33(140).
Fig. 34(141).
Fig. 35(148).
Fig. 36(154).
Fig. 37(164).
Fig. 38(150).

A reentrant into the face of Ridge D, showing pancake ice, ice
balls, and slush enough in the water to cause it to have a grey
color. 2 March 1971.
Looking westward at about 1000 from the visitors' center across
the icefoot to broken second lagoon ice and an isolated portion of
Ridge D. A saw-cut made in the wall of a breach in Ridge D shows
near the right end of the isolated block. 3 March 1971.
Same view as the preceding, but taken at about 1400. The loose
second lagoon ice of that morning has been swept away by an increasingly rough sea from the northwest. Note the saw-cut of the
day before near the right end of the Ridge D block. 3 March 1971.
View northwestward from Ridge B to newly augmenting Ridge C. Spray/
slush ice being thrown over the ridge and covering the old sandy
surface. 3 March 1971.
Detail of the surface of Ridge B at the time Ridge C was receiving augmentation. Sun-warmed sand has melted into the ice and
accumulated as a surface lag-concentrate. Differential melting of
iceballs in apparent proportion to the sand they contained. 3
March 1971.
Extensive augmentation of Ridge C continuing, with an active blowhole. 3 March 1971.
View southward along the top of Ridge C. Slush and spray coming
over the ridge face, and an active blowhole, are shown. 3 March 1971.
Wave breaking on the face of Ridge C; spray, slush, and iceballs of
several sizes being thrown onto the ridge. 3 March 1971.
View northward from the cofferdam. Ridges A and B are low, sandladen and melting. Loose lagoon ice, and only pieces remaining of
Ridge C. 5 March 1970.
Ridges A and B low and sand-laden; lagoon ice refrozen; remnants of
Ridge C (with some recent accretion?) at left. 16 March 1970.
Looking northward along the beach from the cofferdam. Ridges A and
B are severely melted and sand-covered. The lagoon ice is melted,
and Ridge C is represented by isolated chunks. 23 March 1970.
Beginning of the no-ice spring condition. A small ridge of sand
along the north wing of the cofferdam in the foreground possibly
represents the sand that had been incorporated into Ridges A and B.
30 March 1970.
View northward along the beach of Cook site. Ridges A and B are low
and sand-laden. Ridge C is still high and has some white-ice addition but its jagged lakeward edge indicates attrition along its
face. 17 March 1971.

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