Monday 8 November 2004
Post Winter Trip
I've just got back from my post-winter trip which is one of the few opportunities we get to leave the base and see some of the sights of Antarctica. Since I didn't get round to writing very much about my pre-winter trip I thought I'd better make more effort for this one, especially since it was so successful.
We set off on Sunday night, slightly earlier than planned after we harrassed poor Ed our field assistant into leaving. The weather had been the best we'd had since the return of the light and we were anxious not to miss out chance to get off base. We'd already done a lot of the packing but it still took a while to lash the sledges and get kitted up so we didn't head off until early evening. With summer approaching that's not a problem - we've basically got 24 hour sunlight again now anyway.
Our first destination was the McDonald Ice Rumples, an area of the Brunt Ice Shelf where the moving ice shelf is grounded against the rock beneath. As the shelf moves it is subjected to tremendous pressure and is torn apart creating some interesting scenery to explore. By the time we'd arrived and set up camp it was around midnight and we were all pretty tired. Our enthusiasm paid off though as the weather was good the next day so we headed out to explore.
We got kitted up in crampons and strapped all the climbing gear we needed to our harnesses. It was only a short walk to the edge of the ice shelf and the view from the top was spectacular. We got a good view of PR Peak - a large section of the shelf which has been upended and is visible from back at Halley. In the distance steam was rising off the sea as areas without ice started to refreeze. We abseiled off the shelf and into one of the two creeks that lie adjacent to the peak. These are gently sloping regions which join the top of the shelf to the sea ice. Further along the coast there are several more Creeks, each of which was formed here in the past and have slowly been pushed westward as the shelf rotates.
The active nature of the region became more apparent as we walked further into the creek towards the sea. Cracks that had been a few centimetres across a week ago (when the last trip visited) were now almost impassable and had to be jumped over. Eventually we had to turn back as the terrain became too difficult to continue. At one point we saw the footprints from the last trip passing across what was now a two metre wide chasm!
On Tuesday we travelled in linked pairs across a crevasse field to get a closer look at the large peak that is such a familiar part of our horizon. Linked travel involves pairs of people connected by a length of rope. If either person falls into a crevasse their partner can stop them falling too far and set up a pulley system to pull them out if necessary. Although crevasses are very common in the kind of terrain we were crossing it is fortunately quite rare for anyone to fall right into one. Large crevasses are usually obvious even if they are covered by thin bridges of snow. Smaller ones tend to catch you unawares but you usually fall forwards so you don't go right in. Rhian proved herself to be the expert in the field of crevasse finding and at one point lost both legs in one.
The peak was inaccessible due to a large drop covered with boulders of ice the size of buses. Quite a few had fallen to the bottom and the regular creaking and cracking noises from all around us reminded us that it was moving all the time. The peak itself is already falling apart, with large cracks all across its face.
In the afternoon a layer of thick cloud had appeared overhead which results in poor contrast, making it difficult to see even quite large features. It's more dangerous to travel on broken terrain in those conditions as it's impossible to see where you're walking so instead we returned to camp and found a crevasse to abseil into. The campsite was surrounded on three sides by them so we didn't have to look far - the one we chose was only 15 metres from our tents. It was about a metre wide at the surface and slowly narrowed as you decended. By the time we got 20 metres below the surface it was only just wide enough to fit into, but it continued below that as far as we could see.
On Wednesday the Sun was out again and although there was a fairly stiff breeze we decided to leave the Rumples and head to the Hinge Zone. We took down our tents, packed up and lashed the sledges and headed inland. Unfortunately the wind remained strong and a bank of cloud appeared on the horizon, threatening to reduce the contrast and force us to camp before we reached our destination. Also Craig had left a small gap in his windproof jacket while skidooing and was suffering from frostnip on his neck. Since we were passing near to Halley anyway we decided to make a dash for the base, sit out the weather and get Craig's neck looked at by the base Doctor.
The next day the wind had dropped off, but once again poor contrast prevented us from going to the Hinge Zone. Instead we decided to head for the coast to look at some of the older creeks formed by the grounded ice at the Rumples. Creek 2 was used to resupply the base the previous summer so had a line of drums marking a safe routine that can be travelled in most weather. It also has a small heated hut called a caboose that offers a few more home comforts than a pyramid tent!
We set off in the morning and set up one tent to give us a bit more space (sleeping 4 in the caboose is pretty cosy). After that we walked down to the sea ice edge which had changed considerably since the last visit. Most of the smooth 'fast' ice had vanished and was replaced by chaotic, lumpy 'chossed' ice. Most likely the fast ice had been blown out to sea by strong winds and replaced with damaged ice from further along the coast. Before heading back we practiced our ice axe arrest technique on a slope at the bottom of the cliffs. This is needed if you are linked and your partner falls into a crevasse - you need to be able to use your ice axe to stop you both from being pulled in.
Friday was another glorious sunny day so we followed to coastline along to Creek 1. There were a few interesting snow
slopes to climb and then a short abseil down onto the sea ice. The sea ice here was more sheltered so there was a much larger area of smooth fast ice. We spent a couple of hours on the sea ice before climbing back up and over Creek 1 towards the caboose at Creek 2. Before heading back we found an incredible ice cave at Creek 2. We walked in the front past snow stalactites hanging from the ceiling then found a way to climb up out of the top of the creek via a crevasse in the ceiling of the cave.
The next day we decided to move to another caboose further along the coast at Windy Bay. After a nice drive along the coast we arrived and in the afternoon we abseiled off the cliff to visit the large emperor penguin colony. The chicks had grown considerably since our last visit and had started to cluster together in creches of younger birds. The creches are looked after by a few adults while the others go out to sea to feed. We couldn't see any open water from the top of the cliffs so it still might be many miles for them to waddle.
Ed, Craig and I slept in the caboose that night, while Rhian opted for a more adventurous option - she slept outside in a snow pit she dug for herself! The pit looked very much like a shallow
grave, but she assures us that when enclosed in her down sleeping back and bivvy bag and sheltered from the wind she was perfectly warm (quite a good tribute the effectiveness of our sleeping bags as the temperature dropped to -27 C overnight). Sunday was our last day so after another short visit to the penguins we packed up for the last time and headed back along the drum line to Halley for a much needed shower and warm bed.
We all realise just how lucky we were with this trip - except for one day on base in the middle we got to explore something every day. As well as getting to see so much of our surroundings I've particularly enjoyed having the chance to learn more polar travel skills. One my pre-winter trip I was very much doing as I was told but by the end of this one I felt confident lashing sledges, driving skidoos, setting up camp, travelling while linked and abseiling and climbing with crampons. Ed has been great at teaching us new stuff and pushing us to try more. It's been great to feel a bit more capable than last time and now I'm looking forward to next year's trips more than ever.
I've added a new gallery with pictures from the trip.
Posted by simon at 9:10 AM