2016-2017 USAP Field Season
Elucidating the Antarctic methane cycle at the Cinder Cones Reducing Habitat
Dr. Andrew Thurber
Oregon State University
Project Web Site:
Supporting Stations: McMurdo Station
Methane is a greenhouse gas that exists in vast reservoirs within the marine realm. Microbial communities in ocean sediments produce methane as they break down organic compounds and also mitigate its release through oxidation. The mechanisms of methane cycling by these benthic microbes are poorly understood. Prior research suggests that methane cycling in polar oceans is particularly dynamic, and microbial oxidation rates occasionally fail to keep up with methane production, resulting in massive methane release to the atmosphere. As climate change alters the rate and variance of methane release, it is important to understand how the microbial methane ‘filter’ responds to fluctuations in methane cycles in polar regions. An expansive microbial mat containing methanogenic archaea and bacteria was recently discovered at the underwater Cinder Cones area. This site provides a unique opportunity to study a benthic Antarctic habitat with active methane cycling. This research will identify the concentration and source of methane within this site and analogous sites in the southern Ross Sea. Researchers will characterize the microbial communities and will quantify the time scales in which the communities respond to methane input. This work could inform future research into the dynamics of early recruitment and community succession of these methane-cycling microbes.
Field Season Overview
Team members are planning a total of 12 dives over the course of their deployment. Most of the dives will be at the Cinder Cones site, with some dives at Little Razorback Island and Turtle Rock towards the end of the deployment. Field sites will be primarily accessed by Pisten Bully, and a fish hut will be provided to cover dive holes. In the event that sea ice conditions do not allow Piston Bully and/or Reed Drill access to the site at Cinder Cones the team will determine another site to access by snow mobile, will create a dive hole using a Hotsy (i.e. hole melter), and will use a Tomato Hut to cover the hole. On each of the dives they will collect sediment samples using small push cores. They will transport those samples back to station in a cooler and will keep them in a small flow through aquarium while processing. Some samples will need to stay frozen (at -80°) and cold (not frozen) during their return to the home institution.
Deploying Team Members