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Part 6: Learning About Ice
Tuesday, November 22, 2005: Back in McMurdo…It’s the same temperature
as usual—high of +18F, low +10F, but it is overcast and the wind bites…
Living on a glacier is not like many other things I’ve experienced.
Glaciers are not shaped like most other things. The broad snowfields
that cover and feed them are symphonies of complex curves, and those curves
can fool the eye. Across these cold contours the only sound is that of
the wind, while downhill at their termini they expose fractured and formidable
cliffs that eject ice with ballistic reports and occasional ruptures that
spawn icebergs.
That lovely helicopter ride took me to the field camp of “event” I-191,
where Karl Kreutz of the University of Maine is collecting a long, thin
sample of the ice that will whisper tales about past climate conditions
here and around the world.
The upper surface of Clark Glacier is shaped like an English saddle
that is perched on a swayback pass in the Olympus Range, one of a row
of ice-bitten mountain ranges that raise their knuckles between the fabled
Dry Valleys. These astonishingly gorgeous valleys and ranges rise from
the McMurdo Sound up to the Transantarctic Mountains, a 3,000-mile-long
uber-range with summits above 12,000 feet that runs across the continent,
passing a hundred miles or so this side of the south pole. East of their
transect lies the East Antarctic Ice Sheet, which forms the Polar Plateau,
an unimaginable extent of ice at a thickness that puts the South Pole
at 9,200 feet above sea level. To the west of the Transantarctics lies
the West Antarctic Ice Sheet, which, while only half the size of the East,
still contains enough ice to raise global sea level by 16 feet if it were
to slide into the ocean, let alone melt, which it is evidently doing (we
wonder how fast, hence Karl’s investigations). Together these massive
frozen reservoirs hold 70 percent of the Earth’s fresh water.
The size of features out here goes somewhere past boggling the mind.
Here by McMurdo Sound, the Transantarctics act somewhat like a snow
fence, thwarting the flow of ice from east to west. The Dry Valleys are
dry because the region is so bereft of snowfall that the glaciers that
carved these valleys have receded, leaving only the classic deep, U-shaped
troughs, as if a Titanic bruin has dragged its claws from the Transantarctics
to the sea.
Antarctica is a desert. It gets the water equivalent of less than five
inches per year, and a lot of that falls on places far from the Dry Valleys.
Their cold, naked, windswept floors are the closest thing we have on Earth
to the surface of Mars.
The by no means diminutive Olympic Range—Mounts Theseus, Peleus, Cerberus,
Orestes, Jason, Hercules, Aeolus, Boreus, Dido, and lovely Electra crest
at perhaps three thousand feet, and they rise from just above sea level—defines
the boundary between Wright and Victoria Valleys, and, just twenty minutes’
helicopter travel from McMurdo Sound, there is saddle-shaped Clark Glacier.
It’s just a little glacier by Antarctic standards: about two kilometers
across the pass it straddles, five kilometers to the south side of the
pass into Wright Valley, and about three to the north into Victoria. The
smooth upper curves of the snowfield lap up onto the horse’s withers and
rump. Karl Kreutz’s camp was positioned in the exact center of that expanse
of ice, on the spot from which the flow of the ice divides and slides
downhill in all directions. It’s odd to think of something as rigid and
brittle as ice as flowing, but it does: at the scale of its movement,
it’s like silly putty. Setting his camp on the divide is important because
Karl wants to study ice that is, relatively speaking, holding still, just
piling up in place and slowly sagging away from the summit in both directions.
Karl is making studies of three alpine glaciers (as contrasted to ice
sheets, which cover whole continents or portions thereof) in the Dry Valleys
region of Antarctica: Commonwealth Glacier, Clark, and Upper Victoria
Glacier. He explained that, like the valleys they fill, alpine glaciers
to some extent reflect the microclimatic events of the place where they
lie, but by studying three, he can begin to distinguish (as he puts it)
“signal from noise.”
He collects his data by drilling holes into the ice and extracting cores
therefrom. Back home at the University of Maine, he decodes the messages
of the ice by measuring things like oxygen and hydrogen isotopes, what’s
in the dust that landed with the snow that has become ice, and what atmospheric
gases got trapped as bubbles as the snow recrystallized and compacted
first into an intermediate stage called firn and then into ice.
Extracting cores requires a drill rig. The drill rig comes with two men
(Terry and Mike) who know its every quirk and requirement, and to this
crew Karl has added Bruce—a graduate student who is working with a subset
of the data generated—and Toby, who is there, “Because I’ll do anything
he asks me and don’t complain when I get cold.”
Toby and Bruce inside the cook tent.
When I joined them, these men had been on Clark Glacier for three weeks.
Their camp consists of three two-man tents, the 8- by 21-foot cook tent
(the one I said looked like a rather jazzy pill bug), the drill rig and
its 36-foot-diameter dome tent, and a latrine. Cooking and eating are
very important events, both for the calories needed to stay warm and for
the sociability it provides. Food storage is not an issue—everything is
frozen solid and stays that way until they thaw it one way or another,
cook, and eat it, and there are no creatures such as mice or bears in
Antarctica there to invade and swipe it. Closer to the water, the rather
aggressive gull-like skuas would be an issue, but not that far inland.
Water is melted from the drill cuttings they bring up with their cores
(it’s a dry drilling system, très environmental). They all take
turns cooking, melting ice cuttings, and washing dishes, working easily
together, adjusting peaceably to each others’ quirks. When Toby fills
the cook tent with smoke, it’s considered all part of the entertainment.
The five men welcomed me to their camp by helping me set up another
tent (they disapproved of the one the field supply center had issued
me and produced another), showed me where the latrine was (they use
a 55-gallon drum with a funnel in it for the bulk of their needs, while
I adapted quickly to an intermediate use of a quart bottle, boldly labeled
“P”). The Dry Valleys, as all of U.S. interests in Antarctica, are stringently
protected. All wastes are flown out. In fact, the extent of recycling
and waste removal in Antarctica are the best I’ve ever seen. It’s all
hauled home to California, but that’s another story for another millennium.
I set up my tent (ensolite, thermarest, “arctic storm” sleeping bag
with fleece liner, couple of the infamous orange ECW duffels, and I’m
home), then watched Terry and Mike cut core for a while. The rig hoist
lowers a core barrel that has its own motor. Terry stands with one hand
on the controls and another on the cable, feeling the workings of the
machinery transmitted from 100+ meters down inside the ice. When he
raises the barrel, the derrick flips it horizontal, they carry the barrel
outside, empty out the cuttings, and run a rod through the barrel to
extrude the core. They were well down into the glacier when I joined
them, and so were getting something less than a meter of 10cm core each
run. Closer to the surface, they do better. They were hitting a lot
of grit that blows in from the surrounding hills. Mike was constantly
sharpening the cutting teeth. Karl stands by to package and record the
lengths of core. Toby helps muscle the equipment or helps Bruce run
radar transects to establish the thickness of the glacier.
It’s painstaking, tiring work that requires devotion to technique.
They move together as if waltzing, listening to classic licks on a stereo—everything
from the Gypsy Kings and Bob Marley to The Beatles and, when Mike gets
his way (it is rumored) a bit of opera. They’re in the cook tent by
8 AM, at work by 9 AM, work through with only a short lunch break until
6 PM at the earliest, turn in most days by 9 PM. They take off one day
per week to clean up and take extra naps. They eat voraciously and read
every printed word they can get their hands on. Saturday nights they
throw an extra tarp on top of the cook tent to make it darker so they
can watch a movie using Toby’s computer and an MP3 player.
But back to the way glaciers trick the eye. Bruce, Toby and I spent
parts of two days dragging the radar gizmo back and forth across Clark
Glacier, running along the horse’s back. The traverse was a kilometer
from camp (and drill rig) to the sides of the measuring in either direction.
Funny though, when we’d get over to either edge of the glacier and look
back, the camp looked like it was up against the opposite wall of the
pass. The foreshortening is fierce. With no towns or roads to use to
judge distance, and for that matter no trees or other organic or manufactured
objects in sight, scale becomes dimensionless. This becomes a problem
if you think maybe you’ll just stroll over to that rock at the edge
of the glacier and take a look; it could be any distance away…the opposite
of “objects in mirror are closer than they appear.”
The camp on Clark Glacier: objects on glacier are farther than they
appear.
It’s not just the distances: that casual stroll goes out across a substance
that will not support human life, so one must take life-support along,
including sufficient additional clothing, food, water, and communications
devices to get one there and back again. One does not go alone. On my
second day there, Bruce took me north to overlook the Victoria Valley.
We carried a quart of hot water each (which starts out boiling; there’s
a special pocket inside the big red parka so it warms twice), a pocketful
of chocolate bars, extra ECW layers, and a two-way radio. We went to
the edge of the snowfield on skis, then continued across an astonishing
array of shattered rock to the overlook. It was a magical moment for
me: at the bottom of the valley lie a series of sand dunes. I had first
heard about them 31 years ago when I first went to work as a geologist,
and now here I stood gazing down on them. But even though they looked
so close that it was tempting to stroll down the hill and take a closer
look, they were still five miles away (one can’t anyway; they’re off
limits, protected from the tramplings of bipeds).
Glaciers begin as snow that compacts and recrystallizes first into
a texture known as firn and then into ice. The firn has a lot of air
in it; in a trench the men cut to examine the snow quality underneath
the camp I could see a lot of void space in the firn layers. As I walked
about the surface, the firn would occasionally collapse, sometimes even
making a whuffing noise and creating a shallow escarpment. Bruce called
these “firn quakes.” I found them entertaining. During one free hour
I walked out a ways away from the camp looking for quaking firn, but
instead found the silence of the Antarctic. When the wind is not blowing
there is no sound there. No sound and no odors, only the rushing of
blood in my ears and the scents of my own body. At first I thought I
heard echoes, but at last realized that it was only the rustling of
my clothing as I turned this way and that looking for the source of
the sound. As I walked on it the snow squeaked in the cold and individual
flakes glittered more intensely than any I’d seen in all my years living
in snow country. The phrase “like a thousand diamonds” came to mind,
except that it was literally millions, spreading out like a carpet of
fortune.
Sleep came easily each night as I was exhausted from the efforts of
the work and staying warm. I crept into my bag in two full layers of
polypropylene underwear, socks, and hat, put on a sleep visor to block
out the light, pulled the bag up over my head, and slept soundly. Each
morning, the inside of the tent and the outside of my bag were covered
in rime.
At the end of the next day we all traveled down to the terminus of
the glacier on the Wright Valley side. I was on waxless skis with metal
edges, but took it very slowly as it was impossible to tell where the
snow was good and where it was a thin veneer over ice. At the foot of
the glacier, I was treated to a view of what had been underneath me
all the while: layers and layers of blue ice, even a cut-and-fill structure
just like some I’d seen in river sand deposits. So there it was: the
glacier was indeed a river of ice. It let off loud cracks and splintering
noises. While we watched only small sections exploded off it, but that
was enough to keep me at a respectful distance.
The homeward trek was all uphill. From toe to crown a glacier’s curvature
is convex, the opposite of a ski hill, so instead of starting out as
a shallow slope and then steepening it did the reverse. At first I had
to take off my skis and pack them up the hill, but after the first kilometer
or so the slope shallowed sufficiently that I could put them back on.
I chuffed along marveling that as I grew more tired the slope decreased,
making the effort the same from bottom to top, a sort of natural Nautilus
machine. This was fortunate as it was five kilometers laterally and
200 meters vertical gain. As I climbed, the sun angle was such that
my million diamonds fractured into all the gemstones of the rainbow:
sapphires, rubies, emeralds, citrines. I was dazzled.
Moving camp: helo tech Melissa arranges a sling load.
The next day we moved the camp from Clark Glacier to Upper Victoria
Glacier. Watching the helicopters—the AStar plus a Bell 212, which can
carry two and a half times the payload of the littler ship—lift the
load in web slings was a wild ballet. Karl went over in an early load,
and in the final load they took the rest of us. The flight over took
us over those sand dunes and past ridges capped with fingers of the
eroded remnants of the Ferrar, a horizontal band of rock formed during
a 3,000-km simultaneous eruption that marked the breakup of the Gondwana
supercontinent 180 million years ago. Our camp at Upper Victoria looked
over the St. John’s Range, more beautiful than any landscape I’ve seen
anywhere in my life. We set up and got right back to work drilling.
That night I lay in my sleeping bag looking out across this view and
just wept.
The view from my tent: St. John's Range.
When we moved the camp, the helicopters brought out a resupply of
foods. I dug through the boxes, inventorying and sorting, and made a
stir-fry of scallops and giant prawns with green beans and carrots over
rice. A few “freshies” had been sent out with the load: three oranges
and two bananas. Terry parsed the bananas among those interested quick
before they turned black in the cold, and as an after-dinner treat,
cut the oranges into quadrants, making two apiece. Fresh fruit is an
incredible rarity in the remote field camps of Antarctica, and these
men had been there almost a month without any. They ate each bit of
their wedges, and Terry set his skins aside to dry on a toasting plate.
I ate only one of mine and left the other on the edge of the table.
I’ve never been fond of oranges that way; they stick in my teeth. Finally,
I noticed that people were looking at the remaining wedge.
“That’s up for grabs,” I said.
Karl’s hand shot out faster than a gecko’s tongue, snatching it into
the cover of his palm. Then, at length, he cut the quarter in half and
offered one of the bits to Bruce. Bruce sighed, looking on it longingly.
“That’s a mighty kind offer,” he said, and ate it with great solemnity.
On my last morning in camp, my seventh day on the ice, I dug from
the frozen food stores all the ingredients of a thank-you present for
the kind men who had supported me in this splendid visit to the ice
wilds: flour, butter, salt, strawberries, blackberries, sugar, and cornstarch.
I put the Coleman oven on one of the stoves and fired it up, borrowed
a vodka bottle to use as a rolling pin, and made them a pie to remember,
sprinkling a little Grand Marnier over the berries to give it a little
extra yum. It was a warm day with no wind, so at lunchtime when the
pie was ready, we sat in our shirtsleeves in outside the cook tent overlooking
the St. John’s Range and ceremoniously consumed the pastry with big
slabs of cheddar cheese. There was silence for several moments as the
men began eating, then Toby said, “Crap, this is the most flavorful
thing I’ve had in my mouth in three and a half weeks!”
The pie
It was a long flight back to McMurdo. I was intensely sorry to leave
the ice, but when the little AStar appeared in the sky—first as a distant
thudding, and then as a growing dot in all that emptiness—I was ready
to see where it would take me. We skimmed off over the mountains toward
the south, flying past towers of rocks like the minarets of the Grand
Canyon mounted on the backs of the Andes, back over the Olympus Range
and two others, then corkscrewing down into the narrows of Taylor Valley
to Lake Bonney, one of a half dozen or so larger frozen lakes that are
strung like little pearls through the valleys. All along the way I snapped
pictures, but finally I was so overwhelmed with the possibilities that
I just set the camera on the movie option and let it roll.
When we landed on a cantilevered helipad, the pilot called out over
the radio to announce the pickup of another passenger, who, it turned
out, was not there. There had been some sort of mixup. The pilot shrugged.
“Well, that doesn’t mean we can’t have a little fun flying home,” he
said, and took the little craft right down the valley toward the sea
ice without lifting up to the level of the peaks.
It’s been a few days now since my return. I’ve been to another fascinating
place since then and have returned, but I’ll write about that in a day
or so. It’s Thanksgiving back in the U.S. I had a turkey sandwich for
lunch and phoned home, once again intensely homesick, then fell into
a deep, narcotic sleep for part of the afternoon. McMurdo will have
its turkey feed tomorrow even though the actual date occurred yesterday
McMurdo time. It’s all very confusing.
More later,
Sarah
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