Friday 23 November 2007

Productivity!

After a few days of sitting around in a windy storm, I awoke Thursday to find conditions....marginal. I stood out on the deck with Toddy and Simon, the science coordinator, surveying the conditions. Toddy - who makes the call on the weather - was pessimistic, as is his job. So, we gave it another hour, and I got the call on the radio - conditions are better, and we're going out. Finally!

So, yesterday was a whirlwind trip around the ice shelf. First, we escorted a Sno-cat (large tracked snow vehicle; I'll show one in the Halley tour soon) to the Precious Bay caboose, a little cabin on the south side of the shelf, maybe 12km away. This caboose was to be removed after sitting there for several seasons. So - surpise - a lot of digging was involved.

Once the bulk of the digging was done, Toddy and I skived off to make a rosette measurement. Have I described rosettes? I can't be bothered to search my blog to find out. So, here it is again.

A rosette is a set of four poles in the snow - one in the middle, and three arranged in a ~100m triangle around it. When we measure it, we put a GPS antenna at the top of each pole, hook it up to a car battery, and let it sit for an hour or so. I haven't bothered to take a picture of a rosette point; but here, I'll poach one from the field report of my predecessor, Kathy:



So, setting up these points is relatively simple - very simple, in fact. The Trimble devices we use have two buttons on them - power, and record. Much less complicated that the Leica GPS devices we use in our permanent setups - but I'll get to that anon.

Once our devices were in place recording, we took off on our skidoos to the Precious Bay coast. The search continues for a relief point - the location where a ship may unload onto sea ice, before making the journey to Halley. This relief point, wherever it is, will form a major part of my life around Christmas time, so I won't go into detail on it now. Suffice it to say, we didn't find a good relief point at Precious that day.

So, we toodled on back to our rosette - passing a big hole in the snow where a caboose stood a few hours ago - gathered our devices, and sped off back to Halley.

Next was the north side of the shelf, where I checked on one of our permanent GPS sites, which wasn't working. These permanent sites are my main reason for being down here - and, like relief, I will save their description for another day. This post is long and rambling enough!

Our final job yesterday, starting around 7pm, was another relief site search at the Creeks, the ragged north side of the shelf. I was getting a bit groggy at this point, mostly from concentrating on a rope for so long (it was tethered riding again; my favourite). We found a reasonably relief point, that might be considered. While Toddy was walking around on it, checking it out, I sat and enjoyed the rugged ice cliff view. I'll grab a picture at some point - a beautiful sunny day, open water in the distance, 2 km of sea ice in between, a sole penguin wandering around about 1km out, and two snow petrels swooping around us, obviously wondering why there were colorful items (us) amongst all that white. Snow petrels are white, agile birds that swoop like swallows. Makes me wonder why they evolved to have this agility - it's not like there are complicated objects in the Antarctic that they need to fly around.

Anyway, at the end of the day, we returned to Halley, and not a moment too soon. Our good run of sunshine disappeared and we lost contrast. Skidooing in no contrast is a surreal experience. You can't tell the sky from the snow, and the surface of the snow is featureless. It's like you're skidooing in the void. My rope is attached to Toddy, a little bit ahead in the void, but other than that, you could be in the null space. Until you fly over a little hill that you couldn't see, and come crashing back into reality for a moment.

Anyway, we got back. And today, another plane has landed bringing more visitors - but I'll talk about that later. And, as many of you probably saw, there was a bit of an incident today with a Canadian-operated ship in British (claimed) Antarctic Territory! I can't add much commentary, except that it happened quite close to one of BAS' other bases (Signy). We may hear more about it from them eventually, but I don't think they were involved in the rescue plan.

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