Too many days since I last blogged, sorry. I have been quite busy, and very tired in the evenings. Today, Steve and Fred left by Twin Otter, taking off around noon. They and the pilots of the plane had intended to stay here for lunch, but a sudden increase in wind from nothing to strong gusts reminiscent of yesterday (more on that in a bit) convinced them to leave in a hurry, while they still could, in case the weather deterioriated. I spent the morning packing up samples that Steve could take out with him – mostly frozen soil specimens – and generally procrastinating. Though, I was somewhat productive in that I was able to clean out and organize my tent, to some extent.
Yesterday was spectacularly windy. We had katabatic winds, which are strong, steady winds generated by a large ice field and associated glaciers. We could do no work outdoors yesterday afternoon, simply because the winds were so strong. We collapsed our tents, rather than see them carried out into the fjord, though happily the winds lessened in the evening to mere windiness and most of us were able to reset our tents and sleep in them, rather than moving into either the kitchen or lab buildings.
A few days ago we finally threw in the proverbial towel regarding the multiplexer / Avensys unit of hardware and software of the FTIR. Multiple valves had failed on the multiplexer, either at the level of the solenoids in the valves or at the level of the electronic control circuitry, and the software was never very easy to work with. Since we had reached the point of using it only to provide power to one chamber at a time to open and close, and we were opening and closing chambers using the button on the chambers rather than the Avensys control software, we moved the relevant bits of electronics from the multiplexer’s large Pelican case into the smaller case that housed the pumps. We weren’t using the 9L/min “purge” air pump, either, so we ditched that, too. This considerably lightens and simplifies the FTIR system, making it much easier to move around in the field here.
Moving the FTIR is something that now happens daily, and the lighter load and reduction from 3 to 2 pieces is a major improvement. The FTIR itself is more-or-less permanently strapped to an open-frame backpack, and the Pelican case, which we refer to as “the green box” can contain the computer and all needed cables and hoses in addition to the pump and some electronics. We have 2 generators, one of which is lighter and smaller than the other and has its own open-frame backpack. This allows movement of the FTIR between sites by one person in one trip if the destination has the other generator, and in 2 trips (or 2 people) if the generator must also be moved. We have enough control cable/hose sets (10m long) and chambers to leave sets at most of our sites, so those only rarely have to be moved, and then generally short distances – the Willows site is only about 100 metres from the Wet Sedge Meadow site, for example, so one pair of chambers and cable/hose sets stays at one of those 2 locations.
With Steve’s departure, we have a new on-site supervisor: Dr. Greg Henry of UBC, who has been studying Alexandra Fjord for nearly 20 years. This afternoon was my first bit of work without Steve’s direct supervision, but everything seemed to have gone more-or-less according to plan. Greg walked around to see what had changed since last year, and admired the soil gas sampling probes I was working on at the “Dryas” site. Steve and I were worried that Greg would consider the probes too disruptive to the environments he is studying, but he said that they seemed OK and was satisfied that we weren’t causing too much damage.
2 comments:
Great to see you in Calgary. How about a little more detail on the people up there with you? Poor Erin.
MOM
Have you found the buried Ur-Quan dreadnought yet up there?
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