Geography Reference
In-Depth Information
189
THE WInD
In the static, lifeless landscape of the deep field, the wind is the only animate
force. It is movement and sound, alternately relentless and fickle. When it stops
and the sun beams down from a cloudless sky, you can strip to bare skin and
immediately feel the warmth. But let one puff of breeze disturb the thin layer of
radiant air, and shivers will well up. When the wind picks up, it buffets the parka
and bites at fingertips, ear lobes, and nose. In its full fury the wind has flattened
tents and thrown men from the decks of ships. At these times it is an awesome,
fearsome force.
During the 1980-1981 field season I was camped between Mount Mooney
and the La Gorce Mountains a few miles from our put-in site on Robison Glacier.
For the better part of the two weeks we spent at that camp, frigid, katabatic
winds poured over us from the polar plateau to the southeast. With wind speeds
generally around ten to fifteen knots and temperatures about minus 10° F, our
days mapping the outcrops in the surrounding area were seldom comfortable,
especially along ridgelines where the wind compressed and accelerated.
The La Gorce Mountains at the edge of the polar plateau are a first obstruc-
tion to katabatic winds that originate deep in the interior of the East Antarctic
Ice Sheet. The flat top of these mountains slips smoothly from beneath the ice
sheet and rises to the northwest to a dramatic escarpment that drops steeply
more than three thousand feet and splays into two major ridge systems (see Fig.
6.2). When the katabatic winds meet the southeast or back side of the La Gorce
Figure S.11. A cloud layer
shoots out from the
escarpment lip of the La
Gorce Mountains. Beneath
it, a plume of snow traces
the dense, frigid, katabatic
wind as it leaves the preci-
pice and plunges into the
valley behind the interven-
ing ridgeline.
