CAREER: Experimental Warming, Permafrost Thawing, and the Loss of Old Carbon from Tundra: Radiocarbon Research and Education to Understand Ecosystem Feedbacks to Climate Change

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Enough carbon is contained in soils and permafrost of northern ecosystems to double current carbon dioxide in the atmosphere. Because of the size and nature of the permafrost carbon pool, decomposition of previously frozen, old organic carbon is one of the most likely positive feedbacks from terrestrial ecosystems to climate change in a warmer world. This project uses radiocarbon measurements as a unique fingerprint for detecting the loss of old soil carbon in combination with an ecosystem-scale field manipulation to determine controls over the release of permafrost carbon. This high-precision isotope research is paired with the continued development and teaching of an intensive short course designed to expose students to the emerging technology of accelerator mass spectrometry for measuring radiocarbon. Increased numbers of radiocarbon measurements combined with more researchers skilled in the interpretation of this data offers great promise towards detecting changes in ecosystem and global carbon cycling. Climate change is altering the world in which we live. At present, increasing greenhouse gases responsible for climate change are largely a result of human activities. However, climate change may alter the natural cycling of carbon in ecosystems far from direct human influence. The permafrost carbon pool is more than 100 times the current annual inputs of carbon dioxide into the atmosphere from human activity, and thresholds at the freezing point indicate that abrupt changes are possible. This research and education plan focusing on radiocarbon is aimed at understanding more broadly whether terrestrial ecosystems will accelerate or mitigate future climate change.