Ice Palaces
Spectacular pressure ridges, glacial crevasses, and ice caves in Antarctica.
One indelible image from the polar exploration classic The Worst Journey in the World
comes when the explorers from the Robert Falcon Scott expedition are
attempting to cross an Antarctic glacier riddled with treacherous
crevasses, and they toss an empty oil can down a crevasse to see how
deep it goes. Apsley Cherry-Garrard describes the terrifying noise of
the can just falling and falling, seemingly into infinity, as they
crouch at the edge in their reindeer skin mittens, peering down. I’ve
been thinking lately about the early-20th-century miscellanea
that got dumped or fell into those crevasses—that oil can, tents,
horses, sled dogs, and the many men who died trying to get across the
continent—and how it’s all been slowly enfolded within thousands of feet
of ice. Glaciologists estimate it will be 60,000 years before the mouth
of the enormous Beardmore glacier spits out those bones.
The glacier, ice, and snow formations of Antarctica are some of the
most spectacular natural wonders on our planet. Even the best photos
fail to convey their colossal scale, ever-changing shapes, and the
prismatic rainbow effects created by sunlight on all the crystals. One
especially spectacular formation called a “pressure ridge” results from
Antarctica’s massive collisions of fresh and salt water: Enormous
glaciers and icebergs composed of fresh water intersect with a bib of
salty sea ice rimming the entire continent. This mismatch of salt water
and fresh water, along with geological forces moving in total
opposition—the glacier sliding slowly into the ocean, and the tides
propelling the sea ice back against the continent—squeeze the two frozen
surfaces together. Along these pressure lines, the ice buckles up,
easily spiking as high as 20 to 30 feet into the air, creating a wildly
zigzagging ridge that runs for miles.
An experienced guide led several Todgham Lab
scientists and me on a tour of pressure ridges near Scott Base;
although the ice on either side of the ridge is solid, the stress line
itself can be precariously fragile, with slushy holes that open directly
onto the ocean water below. Weddell seals take advantage of these
openings to pop on and off the surface, but we humans preferred to
remain both dry and alive, so we used ice picks to test stability and
thickness at every step.
Antarctica contains 90 percent of the world’s glacier ice,
approximately 6 million cubic miles; the glaciers are riddled with
cracks that could easily engulf the Statue of Liberty. Though
terrifyingly deep, some crevasses can be just a few inches or a few feet
wide at the top, and loosely blown snow often covers and clogs their
openings; many a polar explorer, many a sled dog team, and even some
contemporary scientists have stepped onto what seemed firm snowy ground
only to plunge hundreds of feet down. The lucky, or the well-tethered,
survive; others have fallen so deep they could not be saved.
For the past five years, NASA has been running a remarkable program
called Operation IceBridge, in which a specially-equipped plane flies
methodically back and forth over the continent making video of these
spectacular glacial surfaces, as well as using radar to measure ice
thickness and a laser altimeter to map the sub-glacial bedrock deep
below. Together this data allows NASA to calculate the total volume of
snow and ice, to monitor annual changes in ice thickness, and most
importantly to predict how much the sea level will rise as global
warming continues to escalate. The IceBridge team often works 16-hour
days to maximize distances covered, which means quite a long time in
tight quarters on a low flying plane. Equipped with an old-fashioned
coffee pot and a microwave alongside altimeters, gravimeters, and
magnetometers on the plane, members of the science team take turns
eating and sleeping in between all the monitoring, videotaping, and
fine-tuning of the equipment.
Jefferson Beck, the videographer on these NASA missions, describes
the experience as sometimes akin to “mowing the lawn” when the IceBridge
plane spends hours flying row after row over unending flat whiteness.
(Parts of Antarctica look flat from above, but the radar is still
measuring critical undulations in the bedrock below.) Beck faces many
challenges to getting good footage: The porthole windows on the plane
are scratched, he has to run from one tiny window to another (leaping
over valuable scientific equipment in the process) as the plane passes
over a spectacular formation, and the turbulence from flying so low to
the ground can be so ferocious that he has to press his body and camera
into a piece of “standard-issue ratty old foam” which he carries
everywhere with him for stability. But Beck says capturing moments of
spectacular Antarctic scenery makes everything else melt away:
razor-sharp ice cliffs plunging straight down into the ocean, or
enormous crevasses splintering apart a glacier surface, so large that
the plane’s shadow is swallowed by these yawning gaps.
What can’t be videotaped from above are the radically beautiful
interior spaces on the continent—for instance, an ice cave inside of a
large iceberg that broke off the continent and began to float away but
got temporarily lodged in frozen sea ice. A few weeks ago the divers Rob Robbins and Steve Rupp
took a few of us to visit one such cave. The extraordinary interior,
dripping with all variety of crystals, icicles, and hoarfrost
formations, rivals the most beautiful palace rooms on Earth. The unusual
combination of salt water and fresh water vaporizing, dripping, and
refreezing within the windless interior of the ice cave allows the
growth of enormous and extravagant crystal shapes. The thin snow walls
allow fluctuating amounts of turquoise light to shine through, and every
color of blue imaginable glows all around you. I know my friends back
home might think it heresy, but I’d go see another Antarctic ice cave
over a baby seal any day of the week.
Jynne Dilling Martin is a poet and a 2013 Antarctica artist-in-residence. She is also publicity director of Riverhead Books, a division of Penguin Random House.
Labels: Antarctica, Environment, Nature, Photography
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