Dr. Charles Koven is an Earth System Scientist in the Climate Sciences Department. His research focuses on the relationship between climate change and Earth’s carbon cycle. He has worked on permafrost feedbacks to climate change, global and regional forest disturbance dynamics, and coupled carbon-climate projections across a wide range of future trajectories to inform climate mitigation.
Dr. Koven was a Lead Author of the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), as well as a Drafting Author of the Summary for Policymakers. He was also a Contributing Author of the Fifth IPCC Assessment Report.
What will happen to the terrestrial carbon sink once we reach net zero?
Currently about half of anthropogenic CO2 emissions are taken up by land and ocean sinks, which on land has been driven largely by CO2 fertilization. While a large amount of research has focused on how these sinks may weaken under further unmitigated CO2 emission scenarios, less focus has been on the behavior of these sinks under highly mitigated future scenarios. Here we ask how we expect carbon sinks to behave if we are able to achieve net zero or net negative carbon dioxide emissions, what are some of the key uncertainties governing these coupled carbon-climate responses to net zero and net negative emissions, and how these dynamics may inform both climate policy and the potential for using biospheric sinks as a form of carbon dioxide removal.