Hello! My name is Emelia Chamberlain and I am a first year PhD student here in the Bowman Lab working on the MOSAiC project. I just got back from a very exciting week in Utqiagvik Alaska for MOSAiC snow and ice training. But first, an overview… As mentioned in an earlier post, the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) project is an international effort to study the Arctic ocean-ice-atmosphere system with the goal of clarifying key climatic and ecological processes as they function in a changing Arctic. Within the larger scope of this project, our lab and collaborators from the University of Rhode Island (URI) will be studying how microbial community structure and ecophysiology control fluxes of oxygen and methane in the central Arctic Ocean.
MOSAiC begins in Sept of 2019, when the German icebreaker RV Polarstern will sail into the Laptev Sea and be tethered to an ice flow. Once trapped in the ice, both ship & scientists will spend the next year drifting through the Arctic. The goal is to set up a central observatory and collect time-series observations across the complete seasonal cycle. This year-long time series will be both exciting and critical for the future of Arctic research, but it is logistically difficult to carry out. The cruise is split up into 6 “legs”, with scientists taking two month shifts collecting observations and living the Arctic life. Resupply will be carried out by other icebreakers and aircraft. I myself will be taking part in the last two legs of this project from June – October 2020, with Jeff, Co-PI Brice Loose (URI), and his post-doc Alessandra D’Angelo (URI) representing our project on the rest of the voyage.
Laboratory training in Bremerhaven, Germany
As one would imagine, with over 600 scientists involved and continuous measurements broken up between multiple teams, this project requires a LOT of advanced planning. However, this is the fun part, as it means we get to travel a lot in preparation! In March, Jeff and I traveled to Potsdam, Germany to participate in a MOSAiC implementation workshop. Shortly after, we took a train up to the Alfred Wegener Institute facilities in Bremerhaven with Brice, Alessandra, and other MOSAiC participants to train on some of the instrumentation we will be operating on the Polarstern. We spent a full week training on instruments like a gas chromatograph, gas-flux measurement chambers, and a membrane inlet mass spectrometer (MIMS). While many of us had operated these types of instruments before, each machine is different and several were engineered or re-designed by participating scientists specifically for MOSAiC.
The bulk of the training was focused on the MIMS, which will be used to take continuous underway ∆O2/Ar measurements from surface waters during MOSAiC. Water is piped from below the Polarstern and run through the mass spectrometer where dissolved gas concentrations are measured. Argon (Ar), a biologically inert gas, is incorporated into the ocean’s mixed layer at the same rate as oxygen (O2). However, while argon concentrations are evenly distributed, oxygen concentrations are affected by biogeochemical processes (photosynthesis and respiration by biota). We can therefore compare oxygen and argon measurements in the water column to determine how much oxygen has deviated from what we would expect through physical air-sea exchange processes (i.e. deviations from biologic activity). From these oxygen fluxes, we can estimate Net Community Production (NCP), which is defined as the total amount of chemical energy produced by photosynthesis minus that which is used in respiration. This is an important balance to quantify, as it is representative of the amount of carbon removed biologically from the atmosphere (CO2) and sequestered into the ocean pool. The goal is to use these continuous MOSAiC measurements to quantify these biogeochemical budgets through time and get a better understanding of whether the Arctic is net phototrophic or heterotrophic – whether photosynthesis or respiration is the dominant process.
PC: Brice Loose (URI)
Field training in Utqiagvik, Alaska
After a productive week in Bremerhaven, this past week we stepped outside the laboratory with a snow and ice field training session in Utqiagvik, Alaska. One of the challenges of Arctic fieldwork is, of course, that it takes place in the frigid Arctic environment. To help scientists prepare for life on the ice and to help standardize/optimize sampling methods for MOSAiC, there were 3 snow and ice field training sessions organized (the two others took place earlier this year in Finland.) This trip was particularly exciting for me, as it was my first time in the Arctic! Not only did I learn a lot about sampling sea ice but I was struck by the dynamic beauty of the polar landscape. No wonder researchers continue to be fascinated with the unanswered questions of this wild ecosystem.
The three trainings that everyone had to complete consisted of snow sampling, ice sampling and snow mobile training. Aside from that, people were able to learn or compare more advanced methods for their sampling specialities and test out gear, both scientific and personal weather protection. I was lucky in that the average -18ºC weather we experienced in Utqiagvik will most likely be representative of the type of weather I will be facing in the summer months of MOSAiC. The winter teams will have to contend with quite a bit cooler conditions.
While in Utqiagvik, we here at the Bowman Lab decided to make the most of this trip by also collecting some of our own sea-ice cores to sample and experiment with. The goal of our experiment is to determine the best method for melting these cores (necessary for sampling them) while providing the least amount of stress to the resident microbial communities that we are interested in sampling for. I will write up a post covering the methods and ideas behind this experiment soon – but in the meantime, please enjoy this excellent go-pro footage from beneath the ice captured by Jeff during our fieldwork. The brown gunk coating the bottom of the ice is sea-ice algae, mostly made up of diatoms. The ice here is only 68 cm thick allowing for a lot of light penetration and an abundant photosynthetic community. At the end, you can also note the elusive Scientists in their natural sampling habitat.
What’s next?
As Sept 2019 gets closer, preparations are likely to ramp up even more. Even though I won’t be in the field for another year, it is exciting to think that the start of MOSAiC is rapidly approaching and after these two weeks of training I am feeling much more prepared for the scientific logistics and field challenges that will accompany this research. However, there is still much more to come. In a few weeks I will be jetting off again, but this time to URI to meet up with our collaborators for more instrument training. And thus the preparations continue…
