A huge cornice failure on Polar Circus on Thursday added a little
excitement to our day, and we thought we should give a heads up.
There was a report yesterday of another failure in the same place
that was heard but unwitnessed.
On Thursday, temps got up to -3.0 in the shade, skies mostly cloudy.
Overall, ice was plentiful and soft, mostly dry. At ~11:30, the sun
had just briefly come on to the uppermost sections of the face and we
had just traversed the big bench in the middle (just above where the
pencil tops out) and were racking up at the base of the headwall when
a summit cornice well to climber's right of the last pitch broke off.
(Yesterday's collapse also occurred at about the same time.) The
sonic boom when it released allowed us just enough time to look up
and witness armageddon carom off the face and come straight towards
us. We just made it under a rock alcove before most of the bench was
strafed with large blocks of ice and rock, including the base of and
first pitch of the headwall. Multiple 3-5m wide impact craters
resulted along the bench.
That said, right now there are still numerous remaining cornices
threatening the upper tier, although none of these are visible from
the threatened area. These were likely formed during reverse loading
conditions by the early winter arctic outflow systems, and are still
extensive along the ridge above the climb. Currently, the sun does
directly hit those to the left of the climb late in the morning, and
the headwall pitches may be exposed to these. Something to watch out
for.
Carl Johnston, RG
Nicholas Rapaich, AAG, ASG
_______________________________________________
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continuity. Conditions differ greatly over time and space due to the variable
nature of mountain weather and terrain. Application of this information
provides no guarantee of increased safety. Do not use the Mountain Conditions
Report as the sole factor in planning trips or making decisions in the field.
Please check out http://acmg.ca/mcr for more information.
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