#crevasses

[postingcards]

a group of hikers poses beside a crevasse on nisqually glacier, mt. rainier rppc by ranapar studios, ca. 1920s

[bergsmotiv]

Jasper National Park, Canada The Athabasca Glacier has many areas with deep crevasses. These crevasses are near the toe of the glacier.

[tealin]

Basler to the Beardmore 4: And Back Again

As usual, the properly formatted post is up at the official blog – caught this too late as usual!

Having had the grand tour of the Beardmore Glacier, we set our course to return to McMurdo.  There was one waypoint we were to hit on the way back, but the first part of the journey was just peaceful ice and cloud as far as the eye could see.

After about an hour of abstract land- and skyscapes, we approached our rendezvous point with history: 79°29'S 170°E – One Ton Depot.  There it is!

One Ton Depot was the name given to the final cache of food and supplies taken out along the route to the pole in the summer of 1911, so that not everything would have to be hauled from base when they set out to reach the South Pole the next summer. It was supposed to be laid at 80°S, but due to a spell of bad weather, the condition of the ponies, and the imminence of the end of the safe travel season, they decided that 79°29’S was far enough. In 1911 that was the prudent decision; they could not have known that, the following year, the last three survivors of the five who reached the Pole would get within that 35½ statute mile margin and could really have done with the extra food and fuel. It is one of the great ‘what if’s of polar history.

Another ‘what if’ hovers around Apsley Cherry-Garrard’s trip to One Ton in March 1912. In Scott’s plans, he called for the dog teams to meet the returning Polar Party out on the ice shelf. Due to extenuating circumstances at base, the dogs were sent out later than called for, and under the command of Apsley Cherry-Garrard, who had never been in a leadership position before and could not navigate with a sextant as the Navy men could. The Polar Party was reported to be in good condition by the last people who had seen them, and, time having passed since the planned rendezvous, were likely to be nearer One Ton than the original rendezvous, he was instructed to go there and then decide what to do.

Just as it had when the depot was originally laid, the weather was starting to break up – Antarctica moves very quickly from summer into winter, and it takes no prisoners. Cherry and the dogs arrived at One Ton on March 4th; over the following week only two days were clear enough to travel, and all were bitterly cold. The dogs were short of food and losing condition, so taking them further would have been a significant risk. On March 10th, Cherry left the extra rations and turned back north. Again, an apparently prudent decision at the time, but one that would haunt him for the rest of his life.

It was a completely unscouted location so we couldn't land, but we did a low tight turn so that I could see the terrain and, more importantly, what was visible on the horizon.  I had heard that One Ton was the furthest south one could reliably navigate by landmarks alone – a convenient location for a young explorer who had failed to get his head around celestial navigation.  The view would be different from a few hundred feet up than it would be from ground level, but with the clear day and calm conditions I could at least guess what might be seen. The impression I had was that the top of Erebus would just poke up from the horizon, there, but as far as I could tell from the plane, one was more likely to see Mt Discovery, which was closer and darker.  

This is a fully zoomed-out view of Ross Island from that loop:

We were closer to Minna Bluff and Mt Discovery; the latter is a smaller mountain than Erebus, but being closer and with more exposed rock, the atmospheric perspective would not blot it out so much.

This is not a fair photo to judge against the previous one for distance, as I have zoomed in here, but you can see how the contrast is much higher on these nearer landmarks.  I think the only way you'd locate Erebus more easily than Mt Discovery from here is if there was enough of an eruption to make a large smoke plume.

When planning this trip with the fixed-wing coordinators, alternatives had been discussed in case the Basler flight didn't work out.  I would get views of the Beardmore from a turnaround flight to Pole, and for a recce of One Ton might join one of the regular maintenance trips out to an automated weather station called Alexander Tall Tower, which is only 25km from the location of One Ton.  All the automated weather stations have names, hence ‘Alexander’; 'Tall Tower' is because it's 30m high with instruments at regular intervals all the way up, to measure what's happening in different layers of air.  

As it happened, the Basler trip came off, but we paid a visit to Tall Tower anyway – in fact we buzzed it: one of the other Kenn Borek planes was out there, having brought its attendant meteorologist plus one of the other media outfits, a film crew making the second series of One Strange Rock.  This crew were my best friends at McMurdo so it was really fun to see them at work, not least because their luck with flights had been much poorer than mine.

Just as One Ton was on the 'Southern Road' in Scott's time, so Tall Tower is on the Southern Road now – a slightly different route, taken by the South Pole Traverse convoy taking supplies from McMurdo to Pole, oriented to go up a different glacier than the Beardmore.  We followed this some of the way back, so I got a good appreciation of the road as a scratch on the cue-ball surface of the ice shelf.  Returning parties tried to use their outbound tracks as much as possible to navigate home; sometimes the light was bad and sometimes they were covered by drift, but they'd often cross the tracks again once celestial navigation straightened them out, and that would put them back on course.  A team of sledges with dogs and ponies is going to leave a fainter scratch than multi-ton tractors hauling vast bladders of fuel, but in a vista of windblown snow, a manmade disturbance can really stand out.

Rather than following the road all the way back, as terrestrial creatures would do, we flew over White Island!  This is the side which catches the wind from the south and east, so is not as white as the side you see from McMurdo.

And as we approached Williams Field, the light was just right to show off the sea ice/Barrier interface south of Cape Armitage.

When we finally piled out of the plane, I thanked Steve enthusiastically for what had been by far the best flight of my entire life.  'Yeah, sorry about the turbulence back there,' he said.

'Oh that was nothing! I've had much worse coming in to Edmonton.'  Which is true; I once made peace with death on a flight into Edmonton through a storm which, later that afternoon, spawned a tornado.

'Yeah, but's that's because you were flying into Edmonton.'

I can't argue with that: the Beardmore is definitely not Edmonton.

An article in the October 1911 edition of the South Polar Times – the magazine whose writing and publication kept the men happily occupied during the dark and crowded months of winter – posited Antarctica as a holiday destination in the distant future when global warming had rendered it balmy.  In this antipodean Switzerland, tourists would travel comfortably by aeroplane over the geography which the men reading the magazine were, at that point, yet to walk across themselves.  Wilson illustrated this article with a gauzy cloudscape and a wonderful spindly yellow biplane like the Wright brothers'.  Cherry, writing on the other side of a war which saw the rapid development of aircraft into nimble and efficient vehicles, knew the future of Antarctic travel was in the air, and thought that sensible.  I wonder if either of them could have imagined such a jolly picnic in the sky, going most of the route to the Pole and back in one day, in time for a nice hot dinner in the Galley.

[terrypratchettparadise]

He thought of the deep crevasses and windy caves of Underlay, and the stories of the creatures that dealt there. Of course, he didn't believe in them. He'd told them, because the handing of an oral mythology was very important to a developing culture, but he didn’t believe in supernatural monsters. He shivered. He hoped they didn’t believe in him.

Terry Pratchett - The Carpet People

[growltaire]

my excuse for everything

[mountrainiernps]

Landscape Language Crevasse (n) – a crack or fissure in a glacier With most of the winter’s snow melted off, more and more crevasses on Mount Rainier’s glaciers are visible. Crevasses are deep cracks or fissures in the ice of a glacier. They form in the brittle upper layers of a glacier, or in places where the ice is moving at different rates. For instance, crevasses can form at the edges of a glacier where the ice drags against the sides of a valley versus the faster-flowing middle of the glacier. Crevasses can be many feet deep and unstable, making climbing the mountain increasingly hazardous. NPS photo of crevasses on the North Mowich Glacier, 8/31/17. ~kl

[connor-burrows]

Glacier Snout II by rolandkunz

[tokior1]