Senior Research Associate
It is becoming increasingly apparent that maintaining global temperature rise within safe limits is no longer achievable by reducing emissions alone. In addition to ambitious cuts in greenhouse gas emissions, excess carbon dioxide will also need to be removed from the atmosphere—both to recover from a now inevitable overshoot in emissions, and also to offset emissions that are difficult to eliminate. Most feasible and scalable carbon dioxide removal (CDR) methods rely on photosynthesis to remove carbon from the atmosphere. The carbon fixed in plant biomass can then be stored in a range of possible ways, such as by sequestering post-combustion CO2 in geological reservoirs, by building ecosystem carbon stocks in soils and trees, or by converting biomass into stable black carbon (biochar). However, there are important environmental, social and economic tradeoffs in using land to provide climate-change mitigation in addition to all the other demands we require of it, such as habitat, food, fiber, and ecosystem services. Large uncertainties remain in how large the maximum sustainable potential is for the biosphere to provide CDR, and in how to achieve an optimized portfolio of methods that make the best use of available resources.
My research aims to address these issues of how best to remove atmospheric carbon dioxide. The main tools I use involve quantitative modeling to provide improved understanding of processes, and improved analyses of impact at both the regional and global scales. I apply these analyses to inform policy decisions about the impacts and most appropriate choices of technology, land use and land management, taking into account economic and environmental trade-offs and synergies, particularly between food security and climate-change mitigation. The main foci of my research in recent years have included soil carbon sequestration; restoration of degraded land; sustainable management of landscapes to integrate climate-smart agriculture, agroforestry, soil and water conservation, and reforestation with non-timber forest products; biochar; and bioenergy with carbon capture and storage. My approaches to these systems have encompassed soil carbon modeling to better understand the processes underlying carbon stabilization; improved cost-effective and rigorous greenhouse gas inventories of national scale programs; techno-economic analysis of biomass conversion technologies; geospatial modeling and analysis of food-security interventions; and integrated assessment of biochar-bioenergy systems.
Woolf, D., Solomon, D., & Lehmann, J. (2018). Land restoration in food security programmes: synergies with climate change mitigation. Climate Policy, 1-11.
Woolf, D., Cowie, A., Lehmann, J., Sohi, S., Whitman, T. & Cayuela, M. (2018). Biochar and climate change mitigation: Navigating from science to evidence based policy. Advances in Soil Science: Soil and Climate. (Ed. Lal, R.) Springer.
DeCiucies, S., Lehmann, J., Woolf, D., Whitman, T., & Enders, A. (2018). Priming mechanisms associated with pyrogenic organic matter additions to soil. Geochimica et Cosmochimica Acta. 238:329-342
Woolf, D., Lehmann, J, Joseph, S., Campbell, C. & Christo, F. (2017). An open source biomass pyrolysis reactor. Biofuels, Bioproducts & Biorefining,11: 945–954.
Woolf, D., Lehmann, J., & Lee D.R. (2016) Optimal bioenergy power generation for climate change mitigation with or without carbon sequestration. Nature Communications 7:13160.
Woolf, D., Milne, E., Easter, M., Jirka, S., DeGloria, S., Solomon, D., & Lehmann, J. (2015). Climate Change Mitigation Potential of Ethiopia’s Productive Safety-Net Program (PSNP). World Bank Report. Cornell University. https://ecommons.cornell.edu/handle/1813/41296
Dharmakeerthi, S., Hanley, K., Whitman, T., Woolf, D., & Lehmann, J. (2015). Organic carbon dynamics in soils with pyrogenic organic matter that received plant residue additions over seven years. Soil Biology and Biochemistry 88, 268-274.
Cowie, A., Woolf, D., Gaunt, J., Brandao, M., & de la Rosa, R. (2014). Biochar, Carbon Accounting and Climate Change, in Lehmann, J. and Joseph, S. (Eds.), Biochar for Environmental Management II.
Woolf, D., Lehmann, J., Fisher, E. M., & Angenent, L. T. (2014). Biofuels from pyrolysis in perspective: trade-offs between energy yields and soil-carbon additions. Environmental science & technology, 48(11), 6492-6499.
Shabangu, S., Woolf, D., Fisher, E. M., Angenent, L. T., & Lehmann, J. (2014). Techno-economic assessment of biomass slow pyrolysis into different biochar and methanol concepts. Fuel, 117(Part A) 742–748.
Woolf, D., & Lehmann, J. (2012). Modeling the long-term response to positive and negative priming of soil organic carbon by black carbon. Biogeochemistry, 111(1–3), 83-95.
Woolf, D., Amonette, J. E., Street-Perrott, F. A., Lehmann, J., & Joseph, S. (2010). Sustainable biochar to mitigate global climate change. Nature Communications, 1(5), 1–9.