Water Sampling
And the Adventure of Science
Avalanche early yesterday morning and quite a big one, followed two smaller ones, off the main hanging glacier over the South Basin. I considered getting out of my sleeping bag to take pics, but my sleeping bag was warm, I was sleepy, and I was quite certain it would all be over by the time I got out there. So I went back to sleep. I should point out that we are well out of avalanche range. Much of the snow underneath the hanging glacier is new, and, if you embiggen the photo, you can see debris on the snow and ice that is also new. Incidentally, some of those floating boulders are about 100 m from the edge of the ice and quite large, perhaps a ton or more in weight. Imagine the energy involved!
Science is like writing, or painting or… it is a lot of small steps, a lot of failures—this sentence doesn’t work, that theme stinks, this experiment did not deliver the expected results, I didn’t expect to go there in my writing. But you can learn from those failures, just as every small step takes you closer to a finished chapter, or a successful experiment. Doing science, or writing, is normally about as exciting as watching paint try, and in all cases, you are standing on someone else’s shoulders.
I spent yesterday morning in the anoxic area of the South Basin. Alessandro Cuzzeri of University of Innsbruck and I were helping Daniel Fillion, of the University of Quebec at Rimouski, with whom I helped build a meteorological station last year, pull water samples from the anoxic layer, which begins at 75 meters.
Anoxic means without oxygen. There is no dissolved oxygen in the water for organisms to use, and oxygen normally is a requirement for life.
Yet microorganisms live in the anoxic layer of Lake Untersee, a layer that does not cover the whole of the lake. There are other lakes with anoxic layers, but Lake Untersee is unique because of its isolation from contaminants, due to distance and permanent ice cover. There is, however, dissolved methane, and some of the microorganisms do feed on the methane, although scientists don’t yet understand the pathway for that process.
Yesterday, Daniel wanted to sample at 100 meters. He previously sampled at 72.5, 85, 91 meters deep because different metabolic processes occur at different depths.
The process went like this. Tie a hammer to a Niskin bottle, which has a spring-loaded top and bottom, to weight it. Tie a line to the Niskin bottle. Make sure top and bottom are open. With the messenger, a steel weight which is part of a Niskin bottle set-up, in one hand, with your other hand, smoothly lower the Niskin bottle 100 meters, which you have pre-marked on your line. When the 100 m mark touches the surface of the lake, drop the messenger. It is strung on your line and you can feel it when it hits the spring-loaded top, closing it. Now start hauling the bottle back up. It helps to have a partner or two because 100 meters of rope coated in ice is not exactly light.
Do that… 9 times, I think, for 18+ liters of water.
Daniel strained the water through a strainer with micron openings to separate out microorganisms so he can freeze them and then, when he has access to the proper equipment, analyze their lipid profile. Each type of microorganism has a unique lipid profile, and if that profile is present, then the microorganism it belongs to, likely is too.
Why do this? Daniel’s particular interest is in primitive oceans: the past deep beyond imagining of our world. However, there is broad interest in his work in Quebec and Canada more largely, because Quebec straddles the St. Lawrence River, which is becoming increasingly anoxic. Scientists need to know, how that will change the microorganism biome that higher forms of life depend upon, and thus the ecological economy of the St. Lawrence. But there are a lot of small steps between those water samples we hauled up from Lake Untersee and useful data.
All photos © Erin Solaro, 2024.