By Dave Risk
As I explained briefly (I think) in an earlier post, the McMurdo Dry Valleys are desert-like deglaciated portions of coastal Antarctica that are of scientific interest for biologists in particular, because of the extreme dryness and cold. Special organisms live here that cling to life on, and in, the rocks. (http://en.wikipedia.org/wiki/McMurdo_Dry_Valleys) For my trip, we will be visiting Taylor Valley (http://en.wikipedia.org/wiki/Taylor_Valley) and staying adjacent to Spaulding Pond (http://en.wikipedia.org/wiki/Spaulding_Pond) at the bottom of the Howard Glacier. Spaulding pond is a biological hotspot, relative to other areas in the Dry Valleys at least. The pond sits directly across from the Canada glacier, so named in ~1910 by Canadian physicist Charles Wright who was exploring the area with Robert Scott. (http://en.wikipedia.org/wiki/Canada_Glacier)
Our trip into Spaulding Pond was delayed by poor helicopter weather. The situation was re-evaluated every 2 hours until at about 4 pm flights were called off. When we did finally get into the field, it was snowing. We broke down the two 1-ton helicopter sling loads that had been delivered days earlier with our science equipment, camping gear, food, and fuel. We erected our large “Polar Haven” tent, and our small sleeping tents for two. A Sigma camp stove furnace was installed in the Polar Haven to keep us warm when working inside. The lavatory tent (ahem) was also erected some distance from the main camp.
I went to visit my long-term measurement station on the first evening after dinner. Unfortunately, the station had experienced a failure over the course of the year, and didn’t record everything we had hoped for. While we had been successful the three previous years in collecting year-round records, we had been less lucky and had only captured some data from the past few weeks. That is unfortunately how it goes sometimes in harsh regions science. There were, however, clear signs that the measurement station could be repaired which gave me hope for the coming year. But, I would have to be busy to undertake and test relatively major repairs, plus finish my other planned experiments. Luckily, there is an abundance of daylight in the polar summer!
The snow persisted for the first 3 days, with an accumulation of several centimetres, all of which is quite unusual for the Dry Valleys. Ian, the 11-time Dry Valley veteran, commented that he had never seen so much snow, or the Valleys so wet, in all his visits. We likely received much of the annual precipitation during our stay. And, it was somewhat cooler than usual for this time of year, with temperatures persistently below -3. Spaulding Pond, which was largely covered by ice when we arrived, froze over completely during the cloudy days. For my colleagues who were flying, or mapping sediment characteristics, the snow either curtailed or totally arrested their research. Trey and Stu fuelled an evening Dry Valley tent party on the 2nd night, which raised spirits significantly. Luckily, my own work was unaffected by the weather, but I certainly felt for the others, and for Trey and Stu whose trip back to Scott Base was postponed a full day owing to cancelled heli movements.
When the sun did arrive, the landscape was transformed within hours. With the low humidity (normally less than 20%), the snow sublimated quickly despite the subzero temperatures. In places, one could even see vapour leaving the soil surface. Though the pond ice and cold temperatures persisted, clear blue sky and brown rock was a welcome sight. Trey and Stu unfortunately missed the beautiful blue sky Dry Valleys. With time, our UAV flights and sediment mapping programs got running. The place became DRY, and coupled with the thinner ozone above the south pole, skin is at risk. I had less trouble with the sun than the dryness. Several times daily I had to slather glycerin cream on my crusty peeling nose, and eventually even had to start putting it IN my nose to help arrest dryness and bleeding. Wind and poor weather returned shortly before our departure, but the departure day itself was stunning, still cool but with clear skies and light winds that allowed some of us to work without jackets.
We pulled out from the field slightly earlier than originally expected, so as to make an earlier northbound Hercules flight to New Zealand. Our original schedule was for a later Hercules, but that became impossible as Board meetings were being held on base, and our original plane was oversubscribed with important visitors. In all, we were in the field for 9 days including our late arrival and early pullout. We still got things done (barely) by making up for the bad weather by making hay on the good days. During the trip, I erected a secondary measurement station to measure the CO2 activity of the Pond and adjacent soils, installed soil gas samplers that I would visit twice daily, and started reprogramming the main station. I filled 400 gas sampling vials, and worked from 8 am – 10 pm most days, with regular breaks in between to help others troubleshoot their technical issues with UAVs, etc. Maggie and Marwan helped me along the way as well, with gas sampling, and to create timeseries maps of the infrared soil skin temperatures across all my sampling sites. The UAV flights mapped features above my sampling area, and my gas data will be useful to them as ground truthing information.
Overall my experience was very positive. Our group was fabulous. The climate wasn’t harsh, or uncomfortable, and in fact I brought too many clothes. Most of all, the place was simply unlike any other. The Dry Valleys are remarkable for what they lack, and what they aren’t. There are no animals, predators to watch for, birds, or even visible insects. On calm days there is no sound except the occasional creak of a glacier, or a crack of the pond ice, or the occasional flap of a helicopter. The armoured soil surface, created by frost and which looks so durable and joint jarring, is actually soft to the touch, as it rides atop layers of fluffy frost-heaved sand. There are no smells – at all. This is a prototypical environment of sterility and sensory deprivation that few will ever experience.
For me, there may be an opportunity again next year as part of Charlie’s group but alas I’ll be back in the classroom, so perhaps a StFX student will again benefit from this polar collaboration like Chris did last year.