This wasn’t just any snow: this was the snow off of the IceTop tanks, which meant that I actually got to see the IceTop tanks (which, if you remember, I’d missed doing when they filled the last one with water last week), check out how clear the ice is (under the snow), and talk with the people who helped with the design. (AND I got to drive a snowmobile…with a trailer behind it. That was pretty cool, too!) So three of us spent all morning on Friday and Saturday driving a snowmobile (with sled) between the 40 IceTop stations, unloading our sled of two ladders, two dustbins, a hand broom, a spade, a window-scraper, a measuring tape, a wrench, two foam thingies and two labeled posts. We’d toss all this gear down into the station—maybe 6 feet below ground level—toss ourselves over the edge after the gear (the beauty of working where there’s snow—this bit was more like sledding), and get to work. Each station contains two tanks, and each tank contains two DOMs and some large amount of optically clear ice. So we’d scrape the snow off the ice in each tank by climbing up the ladders, unhooking the sunshades that protect the tanks, sticking our butts way up in the air to bend over the edge of the tank, and using the scraper, the hand broom and two dustbins to collect the snow and toss it over the edge. Then we’d uncover all the cables outside the tanks using the spade, unscrew a plug (using the wrench) and stick the posts where the plug was and surround each one with a foam thingy to keep it upright. (The posts label each tank and stick way up above ground level so that when the stations become completely covered with snow we can still find them—ha ha!). Then we’d measure the height of the posts, take some photos inside the tanks, make notes of how much snow was on them, toss our gear back out over the edge of the stations, and scramble up the embankments. By the end we could do each station in about 15 minutes—depending on how much snow had collected on the ice (due to variations in orientation, some stations had half a foot of snow while others were just dusted with frost). After awhile this got a bit cold, but it was really exhilarating to be doing something constructive with my mornings! (Of course, I only spent 2 mornings doing it…). It also made me very hungry.
In the afternoons I ran another SPAT for dom-testing (which I won’t describe because you surely know the drill as well as I do by now), and then on Saturday evening I got to help deploy a string! Well, only the very beginning of a string before our shift ended, but still—pretty cool! Here’s how it works—the first step toward deploying a string is to drill through the fern layer—this is the layer of snow on top of the actual ice. This layer is maybe 50 ft. So we have a firn drill (which is more like a standard drill) that drills through that layer and after that we start the hot water drilling, which is really like using a firehose with a fancy nozzle and pointing it down at the ice. The special nozzle sprays water in all directions so that the ice melts evenly. The drillers work for maybe two days total until the hole is the proper depth of 2500m. (That’s two days unless the fern drill runs into something—like meat stores that were forgotten about and buried under 30ft of ice. This happened the other day and things took a bit longer for that hole. It also takes longer if there’s a problem with the hot-water hose, because if you shut off the hot water the hose freezes—this also caused some delays last week.) Then the drillers reel up the 2.5km of hose and clear out to the next hole. Now, don’t be deceived, we have it pretty posh these days—we drill and deploy inside mobile structures, called “tosses”. (The structures actually have serial numbers TOS1##### and TOS2##### which I assume is how they got their names.) Back in the early days they drilled and deployed outside, until they had the bright idea to block the wind with things like parachutes (apparently standing behind parachutes actually helped more than it got in the way, but I can’t imagine how). The TOS isn’t warm, per se-although it is heated—simply because it’s raised a few feet off the ground and isn't insulated (and because there’s a big hole going down 2500 m into ice which causes a slight draft of cold air to be constantly blowing through each TOS)—but it does block the wind, which helps a great deal. Anyway, back to how this works. The drillers finish and move on to the next TOS. Then the deployers come in and deploy a string while the drillers are drilling the next hole. Actual deployment takes about 5 hours, but there is lots of preparation which happens ahead of time, like un-boxing the DOMs that Jens and I have tested, sorting them, making sure each DOM has a form to fill out as it’s deployed, and all sorts of other things I don’t know anything about. Obviously, by the time I arrived on site most of this was done, though because we were a bit early (the time is hard to predict) we saw the last of the drilling equipment being removed from the holes. Once this happened we hooked up all of our main data cables and things and then we could finally begin. I was, of course, on DOMs. My job was to bring the DOMs from where they’re stored in the tos, remove the tape from the cables, remove the caps from the connector at the end of the each cable, insert a teeny tiny blue o-ring using a special o-ring insertion tool, and then, after the DOM itself is attached to the main cable, unspool the DOM cable as the DOM is lowered into the hole. This may sound really easy, but as a beginner it was a bit stressful and the pace is uneven, so sometimes I wasn’t doing anything, and other times it was too quick. But it was fun and interesting, and once again it was great to be doing something useful with my time.
Today before spending my afternoon DOM-testing, we finished off the deployment with the cable drag. This is where we drag the connector of the main cable over to the IceTop station where it will be hooked up for data-taking. I even found this interesting, though it involved a lot of standing around and waiting to be told to “Pull!” or “Stop!”
Until now, I really had no idea how all this worked. In fact, one of the most frustrating things about being here has been to be told “Oh, if you have free time just work on your analysis.” That’s silly. I can work on my analysis anywhere in the world, I can’t learn about the project from anywhere but here. So this entry may be boring to most of you, but to me this is the best part. This is what I’m here for, and to finally be doing things—to finally understand how things work on this project that I’ve donated 4 years of my life to (probably more since high-stress jobs shorten your lifespan)—is so cool it’s unbelievable!