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By Peter Rejcek
Somewhere not too far from the U.S. Antarctic Program’s
largest field camp on the West Antarctic ice sheet sits
Charles Bentley’s record collection of chamber music,
entombed in the ice with the rest of Byrd Station.
One of the first research outposts established by the
United States during the International Geophysical Year
(IGY) in the late 1950s, Byrd Station still holds fond
memories for Bentley, who spent two Antarctic winters
there beginning in 1957.
On his way north after 25 months straight on the continent,
Bentley lent the records to an incoming seismologist,
who promised to return them.
“He never brought them back,” he says wistfully.
“My records are still out there. I always had the
idea that I could go back and get them.”
That opportunity never presented itself, despite 15 trips
to the Ice over six different decades, a total of 18 field
seasons. Now, at age 78, Bentley is back in Antarctica,
the principal investigator with Ice Core Drilling Services
(ICDS) from the University of Wisconsin-Madison.
Funded by the National Science Foundation, ICDS supports
researchers wherever a hole needs drilling in the ice,
whether it’s in the Arctic, the Antarctic or a remote
glacier in the Himalayas.
In this particular case, Bentley is headed to the WAIS
Divide field camp, where ICDS will take a deep core, some
3,500 meters long, over the next three field seasons.
He has yet to see the drill in action. WAIS Divide is
a middle-of-nowhere kind of place, about 1,600 kilometers
from McMurdo Station, the logistics hub of the U.S. Antarctic
Program.
For Bentley, whose career as a glaciologist and geophysicist
began not far from the current deep-core operation, that
lonely and cold spot has another name. “I’m
practically back home after 50 years.”
Well, almost. At this particular moment, Bentley, neatly
dressed in professorial slacks and a button shirt neatly
tucked in, is still at McMurdo Station. An unusually intense
summer snowstorm in January is sending snow horizontally
across the town. He worries that weather — either
here or at the field camp — might cut his trip short
or ruin it altogether.
Bob Morse is one of the people responsible for recruiting
Bentley out of retirement to head ICDS. Formerly a professor
at the University of Wisconsin-Madison and principal investigator
of the South Pole neutrino project called AMANDA, Morse
convinced his friend of 20 years that the university needed
his expertise to win the ice-drilling contract.
“I sort of leaned on him to be the PI, and I think
the rest is history,” Morse said on a cell phone
from Honolulu, where he is now an adjunct professor with
the University of Hawaii and a collaborator on AMANDA’s
successor project, IceCube.
“Not many people get it right the first time —
maybe Mozart — but Charlie Bentley always seems to
be very close to the right answer the first time for the
most part,” Morse said. “He’s a hard guy
to please, because he’s very exacting. But at the
same time, it’s very rewarding to work for him. He’s
that wonderful combination of excellence and great inspiration.”
The fresh PhD
Bentley has a bit of time to kill, and indulges a curious
reporter, who prods him about the danger and excitement
that surrounded those pioneering days of the IGY, when
dozens of nations committed to a coordinated campaign
of peaceful research at the poles, around the world and
into outer space.
The media hoopla that surrounds such endeavors today
didn’t exist in the 1950s. Bentley’s own recounting
of how he signed onto an adventure of a lifetime sounds
so matter of fact, as if the decision was obvious.
Geophysicist Frank Press, who would later become president
of the U.S. National Academy of Sciences, popped over
one day from a nearby office looking to recruit Columbia
University students to take part in the IGY.
“He just came across the hall and asked if anyone
here wanted to go to the Antarctic,” Bentley recalls.
“I thought that sounded like a pretty good idea,
so I signed up.”
To prepare for the task ahead, Bentley journeyed to Greenland,
where with the aid of textbooks, taught himself polar
survival skills and collected geophysical data, which
he used for his doctoral thesis. The ink not yet dry on
his diploma, the 26-year-old flew to Panama to catch up
with the U.S. Navy ship carrying scientists to the Ross
Sea in 1956.
“I was about as fresh a Ph.D. as you could be,”
he says.
But just about everyone was a rookie, with most of the
scientists and Navy personnel supporting the IGY 20-something-year-old
men. Bentley says it was rare to meet anyone older than
40 in Antarctica. (Female scientists wouldn’t join
the fray on the continent for more than a decade.)
Dramatic discovery
In January 1957, and despite their inexperience, Bentley
and a handful of scientists left Little America, a U.S.
base located on the edge of the Ross Ice Shelf, for Byrd
Station on tracked vehicles called Tucker Sno-Cats. Along
the way, they conducted experiments to gauge the depth
of the ice sheet.
To their astonishment, they discovered it was as far
below sea level as above, meaning they were traveling
over a former marine area and not subglacial mountains
as everyone had assumed until then. Bentley still calls
the discovery the most dramatic of his career.
Today the finding is particularly poignant in a global
warming scenario. A marine-based ice sheet like the one
over West Antarctica is more vulnerable to melting and
collapse. Its complete dissolution could raise sea level,
according to the most quoted climate models, by six meters,
about 20 feet.
“It’s a terrible threat,” Bentley says.
Wintering at Byrd
But those startling projections were still decades away.
The scientists in 1957 were excited about the data they
collected. It would keep them busy for much of the approaching
winter after they reached Byrd Station.
“We had a lot of data to work on at Byrd Station,
and that was a major source of entertainment, mainly because
of the interesting stuff we were finding out,” Bentley
says. That’s a good thing, as other entertainment
was scarce.
“Well, hardship meant that our pool table didn’t
get out there, our ping-pong table didn’t get out
there, we were low on brandy and hard liquor, [and] the
beer froze. But that’s not hardship. We had plenty
to eat, we had good food, we had a warm place to live,
we didn’t have to work very hard,” he recalled
in an oral history interview with Dian Olson Belanger
in her seminal book on the era, Deep Freeze: The United
States, the International Geophysical year, and the Origins
of Antarctica’s Age of Science (University Press
of Colorado, 2006). (See related story in the Oct. 29,
2006 issue of The Antarctic Sun. )
The young researchers also spent time that winter preparing
for their upcoming traverse across the white unknown of
West Antarctica. The trail from Little America to Byrd
had been marked with flags and 55-gallon drums. No clear
road lay ahead for their 1957-58 traverse.
“We realized we were going to be on our own, so
maybe we should learn how to navigate,” Bentley explains.
“So we spent a good part of the winter teaching ourselves
celestial navigation.”
Into the unknown
Learning celestial navigation wasn’t easy, even
for a group of Ph.D.s, particularly in the cold of winter.
In the summer, they practiced using the sun as a navigational
guide. Finally, in November 1957, they rumbled away from
Byrd Station to the interior of Marie Byrd Land.
“We never had much sense of danger. We never were
in much danger,” Bentley insists. He believed at
the time that they would encounter few, if any, crevasses.
If they did encounter one, they would simply turn in another
direction. The strategy worked.
“[We] only found one crevasse when we started to
drive up on the side of the mountain, which is something
we weren’t supposed to be doing anyway,” he
says ruefully. It only worked, he admits, because the
team drove east rather than west — zigged instead
of zagged — where ice streams riddled with crevasses
awaited them.
“We lucked out, and went in the crevasse-free direction,”
he adds.
As the expedition’s seismologist, Bentley took charge
of measuring the underlying snow and ice. The process
involved unrolling hundreds of meters of cable outfitted
with geophones (a sort of motion detector) and setting
off explosives that sent sound waves down to the base
of the ice sheet below. In this way, they were able to
measure the ice thickness and the depths of reflecting
layers within the ice.
Surprises also awaited the team above the snow —
a group of mountains had appeared on the horizon. Bentley
says the team believed they saw just a few small peaks,
and each morning expected to reach the outcrop of hills.
“This went on for a couple of weeks,” Bentley
says. “We saw this great spread of mountains that
was totally uncharted. As far as we could tell, we were
the first people to see these mountains. … It was
spectacular.”
Mount Bentley, at 4,274 meters, in what is now called
the Ellsworth Mountains, bears his name.
Old and new science
Unsure if he would ever return to the continent —
the IGY was to end in 1959 — Bentley volunteered
to stay a second winter at Byrd and led another traverse
during the 1958-59 austral summer. But it turned out the
United States was in Antarctica to stay, and so was Bentley.
He worked on several more such traverses around the South
Pole until the NSF canceled the program in the 1960s.
He made his most recent visit to the continent in the
mid-1990s.
Bentley credits Paul Mayewski, director of the Climate
Change Institute at the University of Maine, for reviving
the overland traverse in the modern era. A principal investigator
for the International Trans-Antarctic Scientific Expedition
(ITASE), Mayewski completed the final leg of a trip to
the South Pole on Christmas Eve 2007. The traverse collected
data that will help the multi-national program reconstruct
the continent’s climate over the last 200 to 1,000
years.
Mayewski met Bentley during the Greenland Ice Sheet Project
2 (GISP2) in the early 1990s. At the time, GISP2 recovered
the longest ice core in the world, at just over 3,000
meters.
The younger scientist, who has trekked across much of
the continent by foot, ski and tracked vehicle since 1968,
credits Bentley and the exploits of his contemporaries
for helping inspire his own career.
“When I was a kid, I read about Charlie’s work
in National Geographic, and was certainly inspired,”
Mayewski says. “I was always very interested in remote
places, and Antarctica always fascinated me, and [the
IGY era] certainly had something to do with my interest
in Antarctica and other remote places.”
Today kids are reading about the work polar scientists
like Mayewski are doing for the International Polar Year
(IPY), a multi-national science campaign much like the
IGY, but focusing on the Arctic and Antarctic in the context
of climate change.
Bentley sees parallels and differences between the two
eras. Most striking, he says, is that 50 years ago the
researchers were busy with discovery and description.
Now, scientists study processes and dynamics, such as
measuring how fast a glacier is moving.
“We had no way of measuring it,” he explains.
“You’re standing on an ice sheet, [but] you
have no idea. It’s not moving fast enough so that
you get the wind in your face.”
Back to school?
The veteran polar scientist is eager to feel the Antarctic
wind once again on his face. But before he heads into
the field, he must take an overnight outdoor course required
of anyone working in the field. Not even Charles Bentley
can play hooky from Happy Camper School.
“So, after 50 years, I have to learn how to survive
in Antarctica,” he says, with a shrug. “I’m
just going to have a good time.”
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