Thanks to its extremely low humidity, the Antarctic atmosphere allows the sun to shine with brilliance and clarity, amplified by its reflectance from surfaces of snow and ice. On cloudless days, landscapes resonate with detail as shadows from the passing sun outline every swash of sastrugi and fragment of rock. (Having enough light was never a problem with low speed film.)Put some haze in the scene, however, and the shadows fade through muted gradations to flat white. It is not good to be traversing under such conditions, when faint signs of crevasses vanish. When a cloud becomes dense enough, it will disperse sunlight uniformly and surface definition will disappear completely, producing the phenomenon known as a whiteout. The flat white of the sky and the flat white of the snow merge into a continuous, blank field, without depth or dimension. The horizon disappears. In this featureless world, one could unknowingly step off a cliff or walk into a wall of snow. If the whiteout is produced by a dense layer of stratus cloud, it is possible to see dark outcrops of mountains many tens of miles away, but become enveloped in cloud and even nearby objects fade completely. In January of 1979, my party was working in the Churchill Mountains to the south of Byrd Glacier. We pitched camp on snow several hundred yards down from a ridgeline of rock that ran along the crest of the mountains, and gave us access to bedrock for our studies. One day our work was cut short by a cloud that materialized and descended very quickly. I still had some samples to collect and measurements to make, so I sent Scott Borg, one of the party members, scurrying back to the tents, with instructions that if the cloud came down on camp before we were back, to blow a whistle at regular intervals. Sure enough by the time that we reached the low point on the saddle where we needed to turn toward the camp, we were deep in the cloud and suspended in white. Scott was tweeting on the whistle and I was whistling back, so we safely marched the distance to camp suspended in a milky miasma. My most memorable whiteout happened during our take-out from the upper Scott Glacier area in January of 1981. The pilot scheduled to fly the plane was a Lieutenant Commander named John Paulus, who was completing his third three-year tour of duty flying and landing ski-fitted Hercules C-130’s all over Antarctica. Nicknamed “Cadillac Jack,” Paulus was the “old man” of the squadron and, among the ranks of VXE-6, was legendary for the places he had landed. For example, he had done the original put-in at our site 11 years earlier, transporting a New Zealand party that were to traverse the length of Scott Glacier with snowmobiles. The Kiwis had hoped to be put down near Mt. Howe, the southern-most outcrop of rock on the planet, but vast crevasse fields in the headreaches of Scott Glacier prevented landing farther south than the La Gorce Mountains. The day of our pick-up the weather was fine. The Herc flew into view. We packed the radio and the last standing tent. The big plane took a long, low pass over the landing site, then lifted into the air and flew away straight into the morning sun. I thought that Paulus must be messing with us, but when the plane kept on its heading to McMurdo, we unpacked the radio and called to see what was up. “Faulty hydraulics” were what was up. One of the skis wouldn’t lower properly. Okay, no problem, see you tomorrow. The following day was again fine, but when we radioed in we heard that we were not on the day’s sched because Paulus wanted our pull out, and he needed a day of rest according to rules. So again, no problem. See you tomorrow. Except that we were running low on food. Furthermore, that night while we slept, a storm came down straight off the plateau, and not just blowing snow, but lots of precip as well. By the time it played itself out 12 hours later, we were deeply drifted in, and a dense cloud had settled into a ceiling at about 7,000 feet. We could see the lower flanks of peaks some forty miles down Scott Glacier, but where snow met sky the whiteout was complete. “Visibility 50 miles, surface definition nil” was our hourly weather report to McMurdo. By the following day the cloud was thinning enough to begin to perceive a horizon, but it still hung in there as a stable ceiling. Paulus was flying a cargo run to the South Pole that day, but he intended to refuel enough to allow him a dog-leg to our pick-up site. We were in hourly contact with the Herc as it flew to the Pole and then launched in our direction. The ceiling was showing signs of thinning, but it held persistently as the plane neared. From above the clouds, the view would have been a flat sea of cottony white with mountains piercing through. Flying down into a stratus cloud without being able to see what is beneath simply isn’t done. However, flying in under such a cloud from an opening might be worth a shot if your balls are big enough. Miraculously, with the Herc about ten minutes out, a hole opened in the ceiling and I saw a patch of blue about 10 miles to the northeast. Paulus was keying the radio as he spotted the hole, circled back, and dropped into it on a header to camp. As he approached, our red parkas were the only points of reference in a sea of white that engulfed his view. The Herc slowly descended, the glacier gently rose, we were standing at the intersection. With a roar, the plane hit the ground precisely abreast of us, and not more than two wing-spans away. The screaming machine turned, lumbered back to camp, and stopped. The giant cargo door dropped at the rear of the Herc and the first man off was Cadillac Jack. With neither hat nor gloves, he strode over to us, took off his sunglasses, and shook the hands of everyone in the party. As I looked into his eyes, I saw an iciness that mirrored the landscape he had mastered through all those years. This mission was truly a fitting, final hurrah. Paulus retired to Montana after that season, but a pleasing postscript to the story is that the following year the powers-that-be named the runway at the Amundsen-Scott South Pole Station, Jack F. Paulus Skiway, in honor of Cadillac Jack.
Gallery – Starshot Drifts
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.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. 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. 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.
Gallery – Random Shots, 1.0
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.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.
Gallery – Mount Discovery
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. 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.) 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. 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.
Gallery – Ice Puddles 3.0
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.