by Matthew Shupe, CIRES/NOAA scientist and co-coordinator of MOSAiC

Our big event today was raising the met tower. After a couple days of installation and sorting out a few instrument issues, we then ran the tower in the down position for another day to intercompare the different instruments while they all sat at the same level. But with all of that preparation finished, we were then ready for the big event. This is one of those events that people talk about; we had a large group of people with us, including the 4-person communications team to be sure and document every move. I admit a certain degree of nervousness. We’ve lifted the tower a few times now and I’m not too concerned about that process. We combine human power, by just lifting and walking the tower into place, with a come-along system at our primary anchor. The problem is that we couldn’t really get an anchor in at the primary anchor point. The ice around the ridge is 5+ meters thick, such that I’m guessing the ridge itself is likely more than 7m thick. So no anchor at that position. Byron had the great idea that we should just anchor the tower to the new Met Hut (formerly the Remote Sensing hut). It is a bit far away, messing up the ideal geometry for tower guy lines…. But close enough. And the building weighs 700+ kg, plus the new equipment inside and all of its friction on the surface. So it is now serving as our primary anchor. As with on Leg 1, we had a big team, 6 of us. One on the guide rope, one on the pusher pole, 3 lifting the tower itself, and me on the come-along. A brief safety discussion, and then away we go. Crank, crank, crank on the come-along; push, push, push on the steadily elevating structure. Pretty smooth again with no major glitches. Took a couple of minutes of hard work and we now have a vertical met tower standing proud out on the ridge extending out from Polarstern into the middle of the MOSAiC floe. High above the ponds and hummocks extending beyond.