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Antarctica, Sentinel Range, Summary of Activities

Summary of activities. A total of 68 climbers attempted 4,897m Vinson Massif, including seven women. Unusually poor weather was experienced in the second half of the season, one reason that only 55 climbers reached the summit, to give a success rate of barely 81%.

In addition to this regular activity, several teams this season had other, more interesting objectives. Undoubtedly the most ambitious of these was the Chilean team, led by Rodrigo Jordan, who planned a lengthwise traverse of the range from north to south, including ascents of some high peaks—two of them virgin, plus a new route on Vinson. This was the first time such a traverse had been attempted, although much of the terrain, such as the Embree, Patton, and Dater Glaciers, had been visited by climbing expeditions in recent years.

However, the Chileans encountered not only poor weather, but difficult sledging terrain, being forced to cross numerous east-west ridges and lower their sledges down technically difficult passes. The team only attempted one of its main unclimbed objectives, Mt. Giovinetto, but retreated due to the cold and high winds on November 29th. They did, however, make the first ascent of a smaller peak, Mt. Segers (2460m), on December 6th. Segers is a rocky peak to the northeast of Vinson, situated above the head of the Crosswell Glacier. After descending the Thomas Glacier, the Chileans made fast time once out of the Sentinels, and after a 368km journey of 53 days reached ANI’s Patriot Hills base camp on January 2nd, from where they were flown out on January 4th.

The Omega Foundation again sent a team to obtain an accurate height for Mt. Shinn, long considered Antarctica’s third highest mountain. Damien Gildea, 33, of Australia, and Rodrigo Fica, 35, of Chile, flew in to Vinson base camp on November 19th and on November 28th occupied Vinson Camp 3, which is situated on the col between Vinson and Shinn and is the normal last camp for ascents of both peaks. Even after the range was resurveyed in 1979, resulting in a revised USGS map, no height was given for Shinn. USGS publications merely defined it as “…a mountain over 4800m.” Gildea had long thought that Shinn was probably lower than this, an idea reinforced by his first attempt to measure the mountain in November 2001 (see AAJ 2002 ppg. 339–342).

The pair left camp at 5pm on November 30th, deliberately late so as to run the GPS unit wholly within one UTC Day, for best data collection. The lower part of the route is low-angled and passed very quickly, but the upper slope steepened, with sections of 55° on poor ice and snow. The upper section was climbed unroped and no avalanche hazard was encountered, save for a large, partially detached shield of hard, hollow ice perched at the top of the slope, immediately beneath the summit seracs. The channel through the seracs was around 60°, but brought the climbers right on to the summit itself, which gives stunning views of the nearby peaks such as Tyree and Epperly.

Once anchored, the pair set up the GPS unit and began logging data, then set up a Marmot summit tent around 5m below the summit on the only flat place available, which was right on top of one of the summit seracs. A handline was rigged back up to the summit, which Gildea used to periodically check the functioning of the GPS unit. The weather on the day was perfect, probably the best of the season, making the job much easier and safer. After logging data for six hours, most of which was spent dozing in the tent, the pair packed up and down- climbed the route, again unroped, until Fica encountered a deep crevasse on the middle slopes of Shinn, cutting across the route.

After returning to camp 3, two days were spent in poor weather, after which the pair quickly returned to Vinson base camp, only to wait several days to fly out, due to more bad weather. Unlike the previous year, conditions on the Branscombe Glacier were relatively soft and snowy, enabling the pair to enjoy a leisurely ski all the way from camp 2 back to base camp.

However, at base camp the pair undertook the second part of their objective, which was to submit the GPS data to the Australian government AUSPOS website, via Iridium satellite phone, and have the results of their work automatically emailed back to them. This process worked flawlessly and the Omega team obtained the new height of 4660.508m for Mt. Shinn. This is around 140m lower than previously thought and therefore a significant contribution to Antarctic science and mapping. A full report of this expedition can be found at www.theomegafoundation.org.

It should be noted that not only had the route up the “headwall” changed considerably from the previous year—much more to the right, to avoid the seracs and crevassing in the center at the top—but that the old camp 2 site, nestled in next to a stable serac just above the corner of the upper Branscombe, had avalanche debris to within 20m of it, this having fallen from the lower cliffs on the south west face of Shinn and crossed the cwm.

In early January, Robert Anderson guided four clients on a new route from the south-west. Anderson had visited this side of Vinson previously, when in November and December of 1992 he climbed two new routes up Vinson, one on the southwest face and another on the west- southwest ridge. The 2003 route was the first time that commercially guided clients had either attempted or completed a new route on any of the highest Sentinel peaks. (See report below.)

Around the same time, regular Sentinels visitor Conrad Anker was attempting another new route on the east side of the mountain, also with clients. Anker, with Chileans Misael Alvial, Andronico Luksic and Maximo Pacheco, was landed on the Dater Glacier. Though the team established a first camp, bad weather prevented any further progress and they were flown out in late January.

Damien Gildea, AAC, Australia