Rate My Professor Mike O’Sullivan

Dr Mike O'Sullivan is a Lecturer in the Department of Mathematics and Statistics at the University of Exeter, affiliated with the Earth System Science research group. His academic interests focus on the terrestrial carbon cycle, its coupling with climate change, and process-based modeling of land carbon fluxes. O'Sullivan plays a significant role in the Global Carbon Budget project, co-authoring annual reports that assess global carbon emissions, atmospheric growth, ocean and land sinks, and budget imbalances. These reports, such as Global Carbon Budget 2019 (4426 citations), Global Carbon Budget 2021 (1930 citations), Global Carbon Budget 2024 (798 citations), and Global Carbon Budget 2025, provide critical data for climate science and policy. He is associated with the Global Carbon Budget Office at the University of Exeter, contributing to syntheses that inform international assessments like those at COP28 and COP29.

O'Sullivan's recent research outputs highlight his contributions to understanding carbon dynamics under environmental stressors. Key publications include 'The global hydrogen budget' (Nature, 2025), 'Emerging climate impact on carbon sinks in a consolidated carbon budget' (Nature, 2026), 'Reduced Vegetation Uptake During the Extreme 2023 Drought Turns the Amazon Into a Weak Carbon Source' (AGU Advances, 2026), 'Increase in plant reliance on past precipitation associated with greening and drying' (Nature Ecology & Evolution, 2026), 'The LULUCF Data Hub: regional- and national-level discrepancies between independent global datasets and national GHG inventories' (Copernicus Publications, 2026), and 'Record-breaking high temperature amplifies the negative anomaly of tropical net land carbon sinks in the 2023-2024 El Niño' (Agricultural and Forest Meteorology, 2025). Additional influential works encompass 'Global carbon and other biogeochemical cycles and feedbacks' (2021, 1206 citations) and 'Scaling carbon fluxes from eddy covariance sites to globe: synthesis and evaluation of the FLUXCOM approach' (2020, 706 citations). He has delivered seminars, including a COP29 debrief for the Global Systems Institute, enhancing dialogue on carbon trends and climate impacts.