The bottles were washed, the syringes were packed, the gloves were nestled into the sampling kits, and the radios were hung with care. It’s not a huge exaggeration to say that I felt like a little kid the night before Christmas as Allie, Kathy, and I prepped for our first field day in the Dry Valleys of Antarctica. A lot of preparation is imperative before leaving for a day to collect water samples. We tackled important questions such as, What are we hoping to analyze? What bottles do we need to prepare? How should we pick our sampling locations? Where do we want the helicopter to drop us off? How should we pack in case there’s bad weather and we are stranded for a few days? What snacks should be bring?
The most time consuming task before going into the field involves washing bottles prior to the collection of water. We are measuring a host of things, such as anions, cations, nutrients, isotopes, alkalinity, temperature, and pH. We collect separate aliquots of water for each so that we can properly store the sample until analysis. For example, the anion bottles are washed with water (not nitric or hydrochloric acid) so that they are not contaminated by the anions contained in the acid. Bottles used to collect dissolved organic carbon need to be glass (carbon sticks to plastic!) and are burned prior to collection so that any preexisting carbon is combusted. While working in an analytical lab, we are always trying to think of ways to reduce the error we introduce into samples. I’m learning a lot from both Allie and Kathy, as they have a wealth of experience and offer creative ways to keep our samples as uncontaminated as possible.
On the day of the helo flight, Allie and I rushed down to the pad to get our pre-flight briefing, which existed of weighing ourselves and our packs, and picking out a helmet. We flew out with Sam, who was offered the opportunity to fly as part of a morale trip (if there’s space in the helo, workers who do not usually get to fly in a helicopter are given chances to do so). Flying in the helicopter was a transcendental experience. We flew over the sea ice on route to Miers Valley, which is glacially carved and contains a lake. Allie is conducting her masters thesis to try to constrain the residence times of inflowing water from the 2 streams that feed Miers lake, which is about 1.5 kilometers in length. Miers has an outflow stream, which makes it more unique than the other lakes in the Dry Valley. For this reason, Miers contains very fresh water (water leaves the other lakes through evaporation, making them saline). When we got to Miers, we hiked towards the streams so we could determine where we should sample them. We also saw a mummified seal on the way there, as well as many incredible rocks. I’m really glad I brought my hand lens down with me, as field camp taught me to appreciate new places by examining them firsthand. Many of them are “ventifacts” which means they are carved out by the intense katabatic winds that sweep through the valleys. The stream sampling process was fun and involved using a syringe to collect water and filter it into the designated bottle. I was in charge of the pH probe and I took temperature and pH measurements by finding a suitable rock to stand on and letting the probe sit in the water. It was so neat to see flowing water in Antarctica for the first time! I already cannot wait to go out into the field again so I can explore the valley some more.
Over and out,