Antarctica in the Summer: Sunshine 24/7

A peculiarity of the polar regions is the cycle of seasons with total darkness and total sunlight. During the Antarctic (austral) summer, the sun traces a circle in the sky that dips low toward the South Pole and elevates toward the north. At the Pole itself the sun traces a perfect circle uniformally above the horizon. The earliest that I have been to Antarctica is the third week in October, and even then the sun settled slightly above the horizon at midnight.

Midnight sun bathes Mt. Discovery in late October, 1975

Perpetual sunlight has its benefits and its drawbacks. In McMurdo it is possible to draw the shades and sleep as one normally does. In the field, however, tents are always brightly lit by the sunlight that floods through their walls. Some folks have trouble sleeping under such conditions, and a variety of strategies exist for coping with the light. One is to draw the hood of a mummy bag down over your eyes. Personally, I feel claustrophobic in a mummy bag and prefer one in which I can roll over without having to take the top of the bag with me. Another option is to wear an eye mask, like the ones issued by the airlines. These work well for blocking sunlight, but unless your head is in a mummy bag, it is out there in the cold, radiating heat from your sleeping body. My personal preference for sleeping is to wear a dark, lightweight, knit hat that I pull down over my eyes just to the top of my nose. On cold nights (relatively speaking) I will pull my bag up to my face with only my nose sticking out. This lets me breathe into the open air without collecting moisture in my bag. Of course, at the end of a hard day in the field, and especially if you’ve had a couple stiff drinks before dinner, simply closing your eyes is all it takes to plunge on deep, restful slumber.

Wake up! The sun's been shining for hours.

Perhaps the greatest benefit of 24-hour sunlight is that you can work as long as you want. At McMurdo and the other USAP stations and helicopter-supported camps, the program runs on a 24-hour schedule, with meals and work hours prescribed. However, a deep field camp operates independently on their own time with the only constraint being daily radio contact from the field. If you have been cooped up at basecamp waiting for a storm to break, a good 12-16 hour day in the field is just the thing to catch up on lost research time and to burn off the pent-up energy. Every morning the comms office at Mac Center does a roll call of all remote field parties; however, they also monitor the radios 24/7 for any traffic, routine or otherwise. Invariably my remote parties drifted off schedule, and we would be either sleeping or, more commonly, off in the mountains when the roll was called. I think that sometimes they wondered, What kind of a show is Stump running out there, that he can’t keep to a 24-hour routine? My answer has always been that you can’t come back in the middle of a climb for a radio call and then just pop back up to where you left off, not without a helicopter. Time is much too precious in the field.

Two-thirds of the way up Mt. Griffith and you expect me to come on down and make a radio call? No way!

When we were really free cycling, our days stretched to 26 or 27 hours. A couple hours in camp for both the morning and evening meals, maybe 10-12 hours out on the rocks, an hour (or less) to shake down the day’s collection, and then sleep till we woke up 10 or more hours later, it generally added up to more than 24.

It is only if you are out working at midnight that you may see the sky turn pink. Queen Maud Mountains, January, 1975.

Gallery – Random Shots, 1.0

This month’s gallery is a selection of random images shot during the 2000-01 field season in the Byrd Glacier area.

The Greening of McMurdo Station, Antarctica

During the 1955-56 Antarctic summer season in preparation for the International Geophysical Year (1957-58), the U. S. established McMurdo Air Facility on Ross Island in the vicinity of Hut Point, the site of the winter quarters of Scott’s “Discovery” Expedition (1901-04.) First built as a staging point for flights supporting the construction of South Pole Station, McMurdo Station became the main U. S. base on the continent a couple of years later when Little America shut down. The site is uniquely situated on a natural harbor in the lee of Hut Point, to which ice breakers can cut a path through seasonal ice for cargo and tanker ships to resupply the station. The seasonal ice provides a smooth surface for aircraft landings early in the season, but the location of the base a few miles north of the permanent ice of the Ross Ice Shelf also allows the U. S. Antarctic Program (USAP) to maintain a second airstrip that serves when the seasonal ice has broken up.

Built on a series of terraces bulldozed from the surrounding volcanic hillsides by Navy Seabees, McMurdo Station began as a hodge-podge of temporary buildings designed to provide the basics for survival and the conduct of science. By 1970-71, my first Antarctic season, a number of more permanent structures had been added, including the Eklund Biological Center and two structures for housing science personnel, the Hotel California and the Mammoth Mountain Inn. Most of the enlisted men and support staff still slept in Jamesways, modular, canvas-covered, quonset-style structures that were surplus from the Korean War.

Although the environment was not nonexistent in the consciousness of USAP, expediency was the order of the day when it came to waste management. Up behind the main part of town was a “boneyard” of broken-down, heavy equipment, front loaders, bulldozers, graders, trucks, and transport vehicles, both tracked and wheeled varieties. Beyond repair (or not?), these behemoths were annually towed out onto the seasonal ice and arranged in a cluster. By the end of the season, the ice was gone and so were the vehicles, gone to the bottom of McMurdo Sound.

Throughout the 1970’s the McMurdo dump was right off the front of the station. All manner of station refuse ended up there, from solid waste including wood and metal, to garbage. During this period, the population of skuas burgeoned, fattened by the rich supply of nutrients that the dump provided. At the same time, the population of Adelie penguins in the rookery at Cape Royds diminished as more eggs and chicks fell prey to the increased number of marauding gulls.

Skuas were not the only birds to pick the McMurdo dump in those days. Kiwis from New Zealand’s Scott Base would come over the hill in the wee hours and glean plywood, sheet metal, pipes, and the like for use at their station. About once a week the dump was incinerated, producing waves of thick smoke that would waft through town if the wind was coming from the west. Raw sewerage poured from an elevated pipe at the end of the dump directly into Winter Quarters Bay. The whole affair was pretty rude.

With Observation Hill rising inthe background, the McMurdo dump burns at the foot of the station. The sewer pipe follows the road down to the dump.

The McMurdo dump reduced to blackened metal following incineration.

Skuas congregate in the McMurdo dump where the pickins were easy.

Raw sewage pours from the end of the sewer pipe into Winter Quarters Bay.

In October of 1978 President Carter signed into law the Antarctic Conservation Act of 1978, which set guidelines for wildlife conservation, specially-protected areas, and pollution control. Pollution control measures were not instituted until 1984, when the U. S. Antarctic Program issued directive no. 84-1, setting forth guidelines for waste disposal which included incineration. During this period the McMurdo dump was moved from the waterfront to a volcanic crater up behind the station where it was out of sight.

During the 1986-87 summer season, Greenpeace established a small base at Camp Evans, several hundred yards down the beach from Scott’s (1910-12) “Terra Nova” hut, which they occupied continuously until 1991. The primary aim was to gain a seat at the table during negotiations for continuation of the Antarctic Treaty after its 30-year term ended in 1991, and to advocate that all of Antarctica be turned into a “World Park.” However, during the first season, members of Greenpeace staged a series of protests at McMurdo Station, highlighting waste disposal practices and causing considerable tension on the base.

During the same summer season, an accident claimed the lives of two men who had strayed from a flagged route to Castle Rock and fallen into a crevasse. In response, USAP established a Safety Review Panel to review safety measures associated with the Antarctic program. Aside from numerous safety measures that they called for in their 1988 report, the panel also recommended an environmental clean-up of McMurdo Station, and studies to determine better ways of treating, disposing of, and retrograding waste. The same year, the Office of Polar Programs issued an implementation plan and schedule for completing the recommended actions.

During the 1989-90 summer season, station personnel began separating plastic, metal, and burnable wastes. I was in McMurdo that year and remember how novel and proper the practice seemed. The clean-up effort that season resulted in the removal by the supply ship of more than 900 tons of waste from McMurdo, including recyclable material, old rolling stock, scrap metal, radioactive and hazardous waste, and explosives.

By 1991-92, open burning at the dump was discontinued, and a 160-foot long wastewater outfall pipe connected to a domestic sewage macerator was submerged to a depth of 60 feet in Winter Quarters Bay. The following season incineration in a temporary incinerator was halted permanently. Since that time all burnable waste has been retrograded back to the States.

When I returned to McMurdo in 2000-01, a full scale recycling operation was set up in the crater where the dump had been. Recycling bins for specific types of refuse were scattered all over the base in living spaces and in work spaces. Everyone participated in distributing their trash into the appropriate bins. The green transformation of McMurdo was complete.

Recycling bins are lined up adjacent to the sicence cargo yard, 2010-11. From left to right the bins are for Cardboard, Wood, Glass, Clothing, Aluminum cans, Paper towels, Plastic, Food waste, Mixed paper, and Hazaradous waste.

A small assortment of recycling cans in one of the sleeping area. Photo by Danny Foley.

The recycling facility at McMurdo (indicated by the green arrow) sits in an old volcanic crater above storage yards at the upper end of McMurdo Station.

Windmills in The Gap between McMurdo Station and Scott Base are a recent addition to the power supply for the stations.

Gallery – Mount Discovery

Mount Discovery, the graceful volcano to the southwest of McMurdo Sound, is a landmark of many moods.

Going Swimming in Antarctica on the Huffington Post

My new piece for the Huffington Post titled “Going Swimming In Antarctica By Accident and On Purpose” has just been posted. It has been adapted from The Roof at the Bottom of the World. Check it out at HuffingtonPost.com.

Climbing for Science in Antarctica

Over the past several months I’ve talked a lot about Antarctica and what it’s like to be there, but I haven’t really said much about what I’ve actually done there and why. My research career has followed two paths, the unraveling of the history of the half-billion year old mountain belt that forms the foundation of the Transantarctic Mountains (TAM) (the Ross mountain belt of my last post), and the application of fission-track dating toward determining the uplift history of the present day TAM. The fission-track story is easier to explain, but even then…. Wikipedia has a good, succinct explanation of the technique if you want to delve into it.

All dating techniques in geology rely on the rates of decay of radioactive isotopes. In order to determine a date, you need to quantify the abundances of radioactive parent and stable daughter isotopes in a sample, which usually means measuring them with a mass spectrometer. Different minerals have different “closure temperatures,” when parent and daughter atoms no longer leak in or out of the crystal. I like to say that this is when “the clock starts.” Fission-tracks are produced by the fission (splitting in half) of atoms of Uranium, rather than by radioactive decay (emission of sub-atomic particles), but the result is the same. In the mineral apatite, fission tracks anneal (heal themselves and disappear) at temperatures higher than ~110° C, and below that temperature they start to be recorded. That’s when the apatite-fission-track clock starts. In the 1980’s it was our coolest clock, barely hotter than boiling water, the kind of temperature that exists only a couple of miles down in the crust. Charting the passage of the 110° C isotherm (temperature horizon) through rock is a window into its history of uplift and erosion.

The story starts in 1981-82 in northern Victoria Land, where I was working out of a large, helicopter camp collecting granite samples from throughout the region. Along for the early part of the season was Andy Gleadow, the Australian fission-tracker from the University of Melbourne. He sat in the fifth seat of the Huey as we flew around bashing off pieces of the mountains for chemical and isotopic analyses back home. Andy was a pioneer in what is known as “vertical profiling,” a sampling strategy wherein one collects samples over as much vertical relief in as limited a horizontal distance as possible. Samples at the top are always older, and samples at the bottom, younger, as they should be since rock cools from above. One morning we collected five samples from sea-level to the saddle between the two peaks at the summit of Mt. Murchison. The helo pilots did a superb job of finding quasi-level patches of rock or snow at places along the ridgeline. It was really slick. We covered 3,400 meters (11,000 feet) of relief in about two hours and the view was lofty.

Mt. Murchison rises directly up from the Ross Sea to its twin-peaked summit at 3,385 meters. The red dots indicate collection sites where helicoppter landings were made in November, 1980.

Andy took the samples back to Melbourne where they were analyzed by his Ph.D. student, Paul Fitzgerald, a New Zealander who was studying the art of fission-tracking. I met Paul in 1985-86 working out of another helicopter-supported camp, this one to the west of Beardmore Glacier. Paul was in the last year of his Ph.D., a very promising lad looking for his next step. I was starting to have kids and looking for a way to cut back on three-month field seasons I’d been putting in mapping up until then. We made a pact. If he would come to Arizona State, set up a fission-track lab, and teach me how to count, I would take him to the highest-relief granite peaks in the whole of the TAM.

For the 1987-88 season, I was back in the dream world of Scott Glacier, along with Paul, brother Mugs (again), and a second climber, Lyle Dean. Our goal was to climb the biggest mountains that we could find and collect them at 100-meter spacing. Furthermore, in the name of Science, we needed to reach the summits where surveyed points allowed us to set our altimeters, essential for controlling the elevation of the sample set. Samples were 10-15 pounds each and we each typically had three or four samples in our packs at the end of the day.

The first profile that we collected was from the top of the eastern buttress of Mt. Griffith, which we named Fission Wall. We climbed the smooth, hard snow slope to the right of the rock face with crampons, sidehilling back and forth, needing to frontpoint for only a short stretch in the middle when the slope reached about 50°. From the top of the buttress, we rappelled for about four pitches, collecting on the steep ground, and then were able to hike down face first from there. A couple of days later we completed the collection of Griffith with a climb to its summit along a similar steep snow slope. The high ridgeline offered a view over into the drainage of Amundsen Glacier and more than a hundred miles beyond. (The opening photo on the gallery on the homepage was shot from this ridge.)

Routes and collecting localities on the Fission Wall and in the background, the summit of Mt. Griffith.

Paul Fitzgerald rejoicing at the top of the Fission Wall.

Mugs setting the rope for our first rappel on the Fission Wall.

Paul summitting Mt. Griffith. The Medina Hills play out to the north where they meet the Ross Ice Shelf. Scott Glacier appears to the right of the figure.

Our second climb and collection was to a summit that we named Heinous Peak. With 7,500 feet of relief, this was the most grueling climb of the season. Being from Arizona, I use a Grand Canyon depth measure when it comes to relief on a mountain. That was 1 1/2 Grand Canyons. From there we moved camp down to Mt. Borcik. The climb followed a chute that is out of sight in the photo. A fault ran through the cleft, and the rock was pretty rotten, but we managed to scramble up through this part. On the upper face we moved over mixed rock and ice to the summit. From there we traversed to the large snow chute and downclimbed. At the bottom of the chute was a cliff that was vertical for the length of our rope, save for about three feet that touched at the bottom. We rappelled down this face and then staggered back to camp so loaded with rocks we could hardly stand. The season ended with our crossing Scott Glacier to the Gothic Mountains where we collected a profile from Mt. Zanuck.

Route and collecting sites on Mt. Borcik.

Two years later Paul and I were back in Antarctica, this time in the the Sentinel Range of the Ellsworth Mountains, that grouping in West Antarctica, which claims the highest altitude on the continent, 4,897 meters (16,066 feet) at the Vinson Massif. Mugs was along again, and the second climber was New Zealander, Rob Hall. The normal route up the Vinson is a steep, scree-littered snow slope on the west side of the Sentinel Range up to a shoulder where you camp, and the following day begin a long, gradual ascent to the summit. From looking at air photos we thought we might be able to drive our snowmobiles down into the glacier that drains the front of the Vinson, and then to drive up to the climbers’ Camp 1. It worked, and from the shoulder we hiked up to about 13,000 feet where we put up a tent for the day we did the summit. Next we drove over to the low spurs in front of the Vinson and collected at scant outcrops on their crests. The day we summitted the Vinson we stopped at our high tent, rested some and drank a brew, then completed the ascent, sampled down to the snowmobiles, and drove back to basecamp, around 16 hours return. In total this profile was about 3,500 meters (10,000 feet) of relief, two Grand Canyons. The results warranted a paper in Science, and we even made the cover.

Routes and collecting sites on the Vinson Massif. We reached the glacier draining the face of the Vinson where the glacier leaves the image in the middle of its left side.

Original image of cloud on the western face of Sentinel Range with the summit of Mt. Shinn peaking out at the top. The Science cover reversed the image.

Gallery – Ice Puddles 3.0

This weeks gallery are more images of cracks in ice. All were taken on a single pond on the crest of Hut Point Peninsula. The honeycomb pattern in the last two images outlines single crystals of ice, rather than being fractures like those in the other images.

Geology of the Transantarctic Mountains

Last week the holidays broke my routine. As I head into the New Year, The Roof at the Bottom of the World has been launched, and I will all too soon be back to the professorial demands of my day job. My resolution for the New Year is to keep this blog going on a monthly basis, with postings on the first of the month, and what better send-off for 2012 than a short, illustrated lecture on the geology of the Transantarctic Mountains? If you do not know the Rock Cycle, a brief primer can be found at this link.

The present-day Transantarctic Mountains (TAM) arose about 40-50 million years ago, as West Antarctica extended and pulled away from East Antarctica, along a master fault located along the seaward side of the mountains. Perhaps not coincidentally, the trend of the TAM follows an old, rifted margin of East Antarctica along which a major mountain belt formed around a half billion years ago. Geologists call mountain-building episodes orogenies, and they give them names. This orogenic episode in Antarctica is called the Ross. As with most sequences of rocks associated with mountain building, the Ross suite of sedimentary rocks were mostly deposited in oceanic settings, in part associated with volcanic rocks, and accumulated prior to and during the mountain-building interval. These rocks were buried deeply and deformed. In the guts of the mountain belt, melting occurred and voluminous magmas rose up into the overlying sequences. Then the whole process shut down and the mighty mountain range was eroded deeply to its core with only a level plain remaining. Deciphering the complexities of the Ross mountain belt has been the primary focus of my research throughout my career.

Kukri is the name given to the erosion surface on the Ross orogenic belt. Between about 350 and 180 million years ago, a thick sequence of sedimentary rocks accumulated on the Kukri erosion surface. The so-called Beacon deposits were laid down mainly by rivers and streams. Ancient glacial deposits characterize the lower portion of the sequence, and a number of layers of coal occur higher up. The Permian seed fern, Glossopteris, and the Triassic mammal-like reptile, Lystrosaurus, date the sequence, and allow correlation with similar sequences of sedimentary rocks found throughout the continents of the southern hemisphere.

The Beacon sequence ends with a brief episode of profuse magmatism, associated with the beginnings of break-up of the supercontinent of Pangaea. Much of the magma intruded as tabular sheets (sills) between layers of the Beacon sediments.

The uplift of the TAM 40-50 million years ago has left no rock record within the mountains themselves; however, sediments in the Ross Sea, offshore of the mountains, record their history of erosion. The final geological event to produce bedrock in the TAM is eruption of the McMurdo volcanic suite. Volcanism has been active at a sprinkling of centers along the Victoria Land coast beginning about 20 million years ago, and continuing to the present-day in the active lava lake on the summit of Mt. Erebus, not far from McMurdo Station and Scott Base.

This photo encapsulates the geology of the Transantarctic Mountains with folded and intruded metamorphic rocks of the Ross orogenic belt capped by the Kukri erosion surface and overlain by Beacon sedimentary rocks, the thin, light-colored beds, which have been intruded by the dark layers of magma. Scale on the cliff is about 600 feet vertical.

The highest reaches of the TAM are flat-topped and blocky, owing to the nature of the horizontal bedding in the Beacon sediments. Mt. Blackburn at the back of the image is the highest summit on the east side of Scott Glacier. The prominant horizontal line below the summit is the Kukri erosion surface. Beneath that all of the rock is Ross granite.

With the exception of the thin band of Beacon sediments in the uplands at the horizon, all the outcrops in this image are Ross igneous and meatmorphic rocks.

The contacts between igneous and metamorphic rocks can be beautiful by virture of their complexity. Pegmatite Point, Duncan Mountains.

A typical exposure of Beacon sediments, Falla Formation on Mt. Falla.

Beacon sedimentary rocks intruded by dark, igneous rocks, south end of The Cloudmaker. Piedmont glaciers puddle out across the rocky flat, merging with Beardmore Glacier at the right edge of the image.

A steam cloud rises from the summit of Mt. Erebus, the active volcano on Ross Island. Castle Rock is the prominent plug in the foreground.

At the summit of Mt. Erebus is a crater within a crater. Within the inner crater a crusted lake of lava continuously convects, releasing steam and other vapors.

Gallery – CTAM Crevasses

Last year I brought in the New Year at the CTAM camp (short for Central Transantarctic Mountains camp.) I had several fantastic flights over extremely crevassed terrain. This week’s gallery is a sampling. The first two images are of Beardmore Glacier, the third and fourth are of Nimrod Glacier, the fifth is of the northeast flank of Mt. Markham, and the sixth is a random image from the middle of nowhere at the edge of the East Antarctic Ice Sheet.

Ascent of The Tusk, Liv Glacier, Antarctica

People always ask when they see this picture, “Is that you out there?” To which I always reply, “No, that’s me behind the camera.” Were it not for a crooked back, I would have been out there with Phil Colbert, and would have missed the shot. Sometimes things work out the way they are supposed to. This peak, named The Tusk by a New Zealand geological party that had traversed the area in the early 1960’s, is a 600-foot horn of pure marble that juts up at the edge of Liv Glacier close to where it enters the Ross Ice Shelf. Overridden by a much thicker Liv Glacier at a time in the past when the ice shelf was grounded and backed into the mountains to higher elevations, the profile of the peak is vertical to overhung in the upstream direction, but tapers smoothly at a consistent angle of about 30 degrees downstream. The peak is basically a walk-up from the north.

The Tusk viewed from the south.

When I first became aware of this beautiful hunk of rock was in December 1970 during my first trip to the Ice. Directly to the north of The Tusk is a shoulder and high ridgeline called Mt. Henson, which had been mapped by the New Zealand party, as having a contact between marble and schist. I had been there is December, 1970, on my first trip to the Ice, landed by a helicopter at the foot of the mountain. My partner and I had climbed to the summit of the ridge and measured and collected the stratigraphic section of the marble and metavolcanic rocks along the ridgecrest.

South face of Mt. Henson, with dark schist on the right side of the massif in contact with the narrow band of white marble and gray metavolcanic rocks to the left.

When we were finished, we high-tailed it off the ridge, dropped the samples by our survival gear, and started hiking straight toward The Tusk with time we thought to climb and collect it. Much to our chagrin, the helicopter came a couple of hours early and we did not even make it to the foot of The Tusk.

Four years later, on my second trip to the Ice, I was working in the Duncan Mountains, directly across Liv Glacier from Mt. Henson and The Tusk. The Kiwis had also mapped a contact between schist and volcanic rocks in the Duncan Mountains. As with the contact at Mt. Henson, they had interpreted it as being conformable, meaning that one group of layered sedimentary (or volcanic) rocks follows on top of another, their beds parallel. In the course of our mapping, we had decided that the contact in the Duncan Mountains was in fact a fault, a break in rocks along which there had been movement or displacement. It now occurred to us that the contact at Mt. Henson might also be a fault, and since I had not given it more than a passing glance in 1970, we decided to cross the mouth of Liv Glacier and check it out.

Charlie Corbato, my advisor, and Phil Colbert check the air photos during the crossing of Liv Glacier. This photo looks south along the medial furrow on Liv Glacier, with a ridge of crevasses immedaitely to the right.

We followed the Kiwi route which skirted a huge and obvious crevasse field on its north side, then locked into a deep furrow up the middle of the glacier that was smooth with snow, but flanked by heavily crevassed ridges on either side. After following this south for a couple of miles, we cut straight across the Liv again. In the furrow we crossed lots of crevasses that were a couple of feet wide and very deep, but because of their width we were able to drive across them comfortably given the length of our snowmobile. But on the far side of the furrow, we encountered wider and increasingly subtler crevasses, and so were forced to probe for a couple of miles. When we finally made it to the far side we sledded to the north of Mt. Henson to have a look at the structure and then drove back into the reentrant to the south of Mt.Henson were we camped.

North face of Mt. Henson, with dark schist on the left and light-colored marble throughout the rest of the massif.

The next day, December 27, we climbed to the top of the ridge and examined the contact close up. It was highly sheared and deformed, and although the layering on either side of the boundary was parallel, the degree of deformation right at the contact led us to interpret it also as a fault.

Contact between schist and marble near the summit on the south face of Mt. Henson.

When I awoke the next day, my 28th birthday, my lower back was spasmed so badly that I couldn’t stand. I lay in my sleeping bag all day with only slight improvement to my pain. The next day I could at least walk and sit on a snowmobile, so we drove over to The Tusk and climbed it. Each step was painful to me, but the incline was so smooth and gentle that I was able to gut it out to the top. When we reached the summit, the bulbous end of The Tusk beckoned immediately to the south. Phil said he was going out to see what the view was like from there. I declined. On the steepest part to the right of the sharp edge leading to the tip, Phil used his hands to scramble along, but otherwise he frictioned his way along on two feet. When he got to where he was going, he stood for about five minutes contemplating the scene then turned and came back. I shot a single photo, as was my practice at the time, of what I perceived to be the best frame of the shot, and that was that.

This is me sitting on the summit of The Tusk with my spasmed back. The tip of the massif is visible to the left.

We made it down, more painfully than I had ascended, and drove the snowmobile back to the Duncan Mountains following our footprints and snowmobile tracks to the spot where we had started this side trip across Liv Glacier. In hindsight we had hung it out more on this traverse than any other in my Antarctic career.