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Staff information

Haewon McJeon

Human-Earth Sys Sci: Decisions
Earth Scientist


Haewon McJeon is a Senior Research Scientist jointly appointed at the Joint Global Change Research Institute and the Center for Global Sustainability through a partnership between the Pacific Northwest National Laboratory and the University of Maryland. His research focuses on the development of low-carbon, carbon-neutral, and carbon-negative pathways for climate change mitigation.

Haewon served as the lead Integrated Assessment Modeler for the two White House reports on deep decarbonization pathways for the U.S. (Long-Term Strategy, 2021 and Mid-Century Strategy, 2016). He also served as the modeling lead for the America’s Pledge project. Throughout his career, he has worked closely with research clients from government, foundations, and the private sector.

He has published widely on the role of fossil fuels in climate change, decarbonization technologies, and decision making under uncertainty. He has published more than 50 papers in peer-reviewed journals including Nature, Science, Energy Economics, and Climatic Change.

Dr. McJeon holds a Ph.D. and a Master’s degree in Environmental Policy from University of Maryland and a Bachelor’s degree in Economics from Seoul National University.

Education and Credentials

  • Ph.D., Environmental Policy, University of Maryland, MD, USA
  • B.A., Economics, Seoul National University, Seoul, Korea

PNNL Publications


  • Gao P., Y. Gao, Y. Ou, H.C. McJeon, X. Zhang, S. Ye, and Y. Wang, et al. 2023. "Fulfilling global climate pledges can lead to major increase in forest land on Tibetan Plateau." iScience 26, no. 4:Art. No. 106364. PNNL-ACT-SA-10687. doi:10.1016/j.isci.2023.106364
  • Pressburger L.D., K.R. Dorheim, T. Keenan, H.C. McJeon, S.J. Smith, and B. Bond-Lamberty. 2023. "Quantifying Airborne Fraction Trends and the Destination of Anthropogenic CO2 by Tracking Carbon Flows in a Simple Climate Model." Environmental Research Letters 18, no. 5:Art. No. 054005. PNNL-SA-178364. doi:10.1088/1748-9326/acca35
  • Surana K., M.R. Edwards, K. Kennedy, M. Borrero, L. Clarke, R. Fedorchak, and N. Hultman, et al. 2023. "The role of corporate investment in start-ups for climate-tech innovation." Joule 7, no. 4:611-618. PNNL-SA-169512. doi:10.1016/j.joule.2023.02.017


  • Bergero M., M.T. Binsted, O. Younis, E. Davis, M. Siddiqui, R. Xing, and E. Arbuckle, et al. 2022. "Technology, technology, technology: An Integrated Assessment of Deep Decarbonization Pathways for the Canadian Oil Sands." Energy Strategy Reviews 41. PNNL-ACT-SA-10584. doi:10.1016/j.esr.2022.100804
  • Cui R., N. Hultman, D. Cui, H.C. McJeon, L. Clarke, J. Yuan, and W. Cai. 2022. "A US-China coal power phaseout and the global 1.5 degrees C pathway." Advances in Climate Change Research 13, no. 2:179-186. PNNL-SA-166672. doi:10.1016/j.accre.2021.09.005
  • Edwards M.R., Y. Cui, M. Bindl, N. Hultman, K. Mathur, H.C. McJeon, and G.C. Iyer, et al. 2022. "Quantifying the regional stranded asset risks from new coal plants under 1.5°C." Environmental Research Letters 17, no. 2:Art. No. 24029. PNNL-ACT-SA-10559. doi:10.1088/1748-9326/ac4ec2
  • Iyer G.C., Y. Ou, J.A. Edmonds, A.A. Fawcett, N. Hultman, J. McFarland, and J.G. Fuhrman, et al. 2022. "Ratcheting of climate pledges needed to limit peak global warming." Nature Climate Change 12, no. 12:1129 - 1135. PNNL-SA-172425. doi:10.1038/s41558-022-01508-0
  • Kintner-Meyer M., G. Conzelmann, H. Kim, N. Zhou, P.J. DeStephano, S. Durga, and A. Elgowainy, et al. 2022. The Net Zero World Initiative’s Preliminary Analysis of Decarbonization Pathways for Five Countries. PNNL-33619. Richland, WA: Pacific Northwest National Laboratory. The Net Zero World Initiative’s Preliminary Analysis of Decarbonization Pathways for Five Countries
  • Kintner-Meyer M., G. Conzelmann, H. Kim, N. Zhou, P.J. DeStephano, S. Durga, and A. Elgowainy, et al. 2022. The Net Zero World Initiative’s Preliminary Analysis of Decarbonization Pathways for Five Countries. PNNL-SA-179337. Richland, WA: Pacific Northwest National Laboratory. The Net Zero World Initiative’s Preliminary Analysis of Decarbonization Pathways for Five Countries
  • Ou Y., G.C. Iyer, A.A. Fawcett, N.E. Hultman, H.C. McJeon, S. Ragnauth, and S.J. Smith, et al. 2022. "Role of non-CO2 greenhouse gas emissions in limiting global warming." One Earth 5, no. 12:1312-1315. PNNL-ACT-SA-10703. doi:10.1016/j.oneear.2022.11.012


  • Arbuckle E., M.T. Binsted, E. Davis, D. Vannucci Chiappori, M. Bergero, M. Siddiqui, and C. Roney, et al. 2021. "Insights for Canadian electricity generation planning from an integrated assessment model: Should we be more cautious about hydropower cost overruns?." Energy Policy 150. PNNL-ACT-SA-10495. doi:10.1016/j.enpol.2021.112138
  • Cui R., N. Hultman, D. Cui, H.C. McJeon, S. Yu, M.R. Edwards, and A. Sen, et al. 2021. "A plant-by-plant strategy for high-ambition coal power phaseout in China." Nature Communications 12, no. 1:1468. PNNL-ACT-SA-10479. doi:10.1038/s41467-021-21786-0
  • Edmonds J.A., S. Yu, H.C. McJeon, D. Forrister, J. Aldy, N. Hultman, and R. Cui, et al. 2021. "How much could Article 6 enhance Nationally Determined Contribution ambition toward Paris Agreement goals through economic efficiency?." Climate Change Economics 12, no. 2:2150007. PNNL-SA-162547. doi:10.1142/S201000782150007X
  • Fuhrman J., A.F. Clarens, K.V. Calvin, S. Doney, J.A. Edmonds, P. O'Rourke, and P.L. Patel, et al. 2021. "The Role of Direct Air Capture and Negative Emissions Technologies in the Shared Socioeconomic Pathways towards +1.5°C and +2°C Futures." Environmental Research Letters 16, no. 11:Art. No. 114012. PNNL-ACT-SA-10539. doi:10.1088/1748-9326/ac2db0
  • Fuhrman J.G., A.F. Clarens, H.C. McJeon, P.L. Patel, Y. Ou, S. Doney, and W. Shobe, et al. 2021. "The role of negative emissions in meeting China’s 2060 carbon neutrality goal." Oxford Open Climate Change 1, no. 1:kgab004. PNNL-ACT-SA-10518. doi:10.1093/oxfclm/kgab004
  • McJeon H.C., B. Mignone, P. O'Rourke, R. Horowitz, H. Kheshgi, L.E. Clarke, and P. Kyle, et al. 2021. "Fossil energy deployment through midcentury consistent with 2°C climate stabilization." Energy and Climate Change 2. PNNL-ACT-SA-10418. doi:10.1016/j.egycc.2021.100034
  • Ou Y., C.W. Roney, J. Alsalam, K.V. Calvin, J. Creason, J.A. Edmonds, and A.A. Fawcett, et al. 2021. "Deep mitigation of CO2 and non-CO2 greenhouse gases toward 1.5°C and 2°C futures." Nature Communications 12, no. 1:Art. No. 6245. PNNL-SA-158423. doi:10.1038/s41467-021-26509-z
  • Ou Y., G.C. Iyer, L. Clarke, J.A. Edmonds, A.A. Fawcett, N. Hultman, and J. McFarland, et al. 2021. "Can updated climate pledges limit warming well below 2°C? Increased ambition and implementation are essential." Science 374, no. 6568:693-695. PNNL-SA-163608. doi:10.1126/science.abl8976
  • Van De Ven D.P., M.I. Westphal, A. Gambhir, G. Peters, H.C. McJeon, N. Hultman, and K. Kennedy, et al. 2021. "The impact of U.S. re-engagement in climate on the Paris targets." Earth's Future 9, no. 9:e2021EF002077. PNNL-SA-165167. doi:10.1029/2021EF002077


  • Fuhrman J., H.C. McJeon, P.L. Patel, S. Doney, W. Shobe, and A.F. Clarens. 2020. "Food-energy-water implications of negative emissions technologies in a+ 1.5° C future." Nature Climate Change 10, no. 10:920-927. PNNL-ACT-SA-10482. doi:10.1038/s41558-020-0876-z
  • Hultman N., L.E. Clarke, C. Frisch, K. Kennedy, H.C. McJeon, T. Cyrs, and P. Hansel, et al. 2020. "Fusing subnational with national climate action is central to decarbonization: the case of the United States." Nature Communications 11, no. 1:Article No. 5255. PNNL-ACT-SA-10500. doi:10.1038/s41467-020-18903-w
  • Kaufman N., A. Barron, W. Krawczyk, P. Marsters, and H.C. McJeon. 2020. "A near-term to net zero alternative to the social cost of carbon for setting carbon prices." Nature Climate Change 10, no. 11:1010-1014. PNNL-SA-151884. doi:10.1038/s41558-020-0880-3
  • Sampedro Martinez de Estivariz J., R. Cui, H.C. McJeon, S.J. Smith, N. Hultman, L. He, and A. Sen, et al. 2020. "Quantifying the reductions in mortality from air-pollution by cancelling new coal power plants." Energy and Climate Change 2. PNNL-ACT-SA-10477. doi:10.1016/j.egycc.2020.100023


  • Bond-Lamberty B., K.R. Dorheim, Y. Cui, R.L. Horowitz, A.C. Snyder, K.V. Calvin, and L. Feng, et al. 2019. "gcamdata: An R Package for Preparation, Synthesis, and Tracking of Input Data for the GCAM Integrated Human-Earth Systems Model." Journal of Open Research Software 7, no. 1:Article No. 6. PNNL-SA-135553. doi:10.5334/jors.232
  • Calvin K.V., P.L. Patel, L.E. Clarke, G.R. Asrar, B. Bond-Lamberty, R. Cui, and A. Di Vittorio, et al. 2019. "GCAM v5.1: Representing the linkages between energy, water, land, climate, and economic systems." Geoscientific Model Development 12, no. 2:677-698. PNNL-SA-137098. doi:10.5194/gmd-12-677-2019
  • Cui R., N. Hultman, M.R. Edwards, L. He, A. Sen, K. Surana, and H.C. McJeon, et al. 2019. "Quantifying operational lifetimes for coal power plants under the Paris goals." Nature Communications 10. PNNL-ACT-SA-10417. doi:10.1038/s41467-019-12618-3
  • Feijoo F., B. Mignone, H. Kheshgi, C.A. Hartin, H.C. McJeon, and J.A. Edmonds. 2019. "Climate and carbon budget implications of linked future changes in CO2 and non-CO2 forcing." Environmental Research Letters 14, no. 4:044007. PNNL-ACT-SA-10335. doi:10.1088/1748-9326/ab08a9
  • Fuhrman J., H.C. McJeon, S. Doney, W. Shobe, and A.F. Clarens. 2019. "Why Integrated Assessment Modeling of Negative Emissions Technologies Is Hard and How We Can Do Better." Frontiers in Climate 1. PNNL-ACT-SA-10465. doi:10.3389/fclim.2019.00011
  • Santos Da Silva S., F.R. Miralles-Wilhelm, R. Muņoz Castillo, L.E. Clarke, C.J. Braun, A. Delgado, and J.A. Edmonds, et al. 2019. "The Paris pledges and the energy-water-land nexus in Latin America: Exploring implications of greenhouse gas emission reductions." PLoS One 14, no. 4:e0215013. PNNL-SA-136697. doi:10.1371/journal.pone.0215013
  • Yu S., J.D. Horing, Q. Liu, R.T. Dahowski, C.L. Davidson, J.A. Edmonds, and B. Liu, et al. 2019. "CCUS in China’s Mitigation Strategy: Insights from Integrated Assessment Modeling." International Journal of Greenhouse Gas Control 84. PNNL-SA-128974. doi:10.1016/j.ijggc.2019.03.004


  • Gillingham K., W. Nordhaus, D. Anthoff, G.J. Blanford, V. Bosetti, P. Christensen, and H.C. McJeon, et al. 2018. "Modeling Uncertainty in Integrated Assessment of Climate Change: A Multi-Model Comparison." Journal of the Association of Environmental and Resource Economists 5, no. 4:791-826. PNNL-ACT-SA-10291. doi:10.1086/698910
  • Iyer G.C., K.V. Calvin, L.E. Clarke, J.A. Edmonds, N. Hultman, C.A. Hartin, and H.C. McJeon, et al. 2018. "Implications of sustainable development considerations for comparability across nationally determined contributions." Nature Climate Change 8. PNNL-SA-121202. doi:10.1038/s41558-017-0039-z


  • Calvin K.V., B. Bond-Lamberty, L.E. Clarke, J.A. Edmonds, J. Eom, C.A. Hartin, and S.H. Kim, et al. 2017. "The SSP4: A World of Deepening Inequality." Global Environmental Change 42. PNNL-SA-115202. doi:10.1016/j.gloenvcha.2016.06.010
  • Davidson C.L., R.T. Dahowski, H.C. McJeon, L.E. Clarke, G.C. Iyer, and M. Muratori. 2017. "The value of CCS under current policy scenarios: NDCs and beyond." Energy Procedia 114. PNNL-SA-121411. doi:10.1016/j.egypro.2017.03.1885
  • Iyer G.C., C.M. Ledna, L.E. Clarke, J.A. Edmonds, H.C. McJeon, P. Kyle, and J. Williams. 2017. "Measuring Progress from Nationally Determined Contributions to Mid-Century Strategies." Nature Climate Change 7. PNNL-ACT-SA-10269. doi:10.1038/s41558-017-0005-9
  • Mignone B.K., S. Showalter, F. Wood, H.C. McJeon, and D. Steinberg. 2017. "Sensitivity of Natural Gas Deployment in the US Power Sector to Future Carbon Policy Expectations." Energy Policy 110. PNNL-ACT-SA-10189. doi:10.1016/j.enpol.2017.08.012
  • Muratori M., C.M. Ledna, H.C. McJeon, P. Kyle, P.L. Patel, S.H. Kim, and M.A. Wise, et al. 2017. "Cost of Power or Power of Cost: a U.S. Modeling Perspective." Renewable & Sustainable Energy Reviews 77. PNNL-ACT-SA-10131. doi:10.1016/j.rser.2017.04.055
  • Muratori M., H. Kheshgi, B.K. Mignone, H.C. McJeon, and L.E. Clarke. 2017. "The future role of CCS in electricity and liquid fuel supply." Energy Procedia 114. PNNL-ACT-SA-10186. doi:10.1016/j.egypro.2017.03.1893
  • Muratori M., H. Kheshgi, B.K. Mignone, L.E. Clarke, H.C. McJeon, and J.A. Edmonds. 2017. "Carbon Capture and Storage across Fuels and Sectors in Energy System Transformation Pathways." International Journal of Greenhouse Gas Control 57. PNNL-ACT-SA-10144. doi:10.1016/j.ijggc.2016.11.026


  • Aldy J., W. Pizer, M. Tavoni, L. Reis, K. Akimoto, G.J. Blanford, and C. Carraro, et al. 2016. "Economic Tools to Promote Transparency and Comparability in the Paris Agreement." Nature Climate Change 6. PNNL-ACT-SA-10174. doi:10.1038/nclimate3106
  • Scott M.J., D.S. Daly, M.I. Hejazi, P. Kyle, L. Liu, H.C. McJeon, and A. Mundra, et al. 2016. "Sensitivity of Future U.S. Water Shortages to Socioeconomic and Climate Drivers: A Case Study in Georgia Using an Integrated Human-Earth System Modeling Framework." Climatic Change 136, no. 2:233-246. PNNL-SA-105762. doi:10.1007/s10584-016-1602-8


  • Barron R.W., and H.C. McJeon. 2015. "The differential impact of low-carbon technologies on climate change mitigation cost under a range of socioeconomic and climate policy scenarios." Energy Policy 80. PNNL-SA-107937. doi:10.1016/j.enpol.2015.01.038
  • Bosetti V., G. Marangoni, E. Borgonovo, L. Anadon, R.W. Barron, H.C. McJeon, and S. Politis, et al. 2015. "Sensitivity to Energy Technology Costs: A Multi-model comparison analysis." Energy Policy 80. PNNL-SA-107392. doi:10.1016/j.enpol.2014.12.012
  • Calvin K.V., S. Rose, M.A. Wise, H.C. McJeon, L.E. Clarke, and J.A. Edmonds. 2015. "Global Climate, Energy, and Economic Implications of International Energy Offsets Programs." Climatic Change 133, no. 4:583-596. PNWD-SA-10499. doi:10.1007/s10584-015-1482-3
  • Fawcett A., G.C. Iyer, L.E. Clarke, J.A. Edmonds, N. Hultman, H.C. McJeon, and J. Rogelj, et al. 2015. "Can Paris pledges avert severe climate change?." Science 350, no. 6265:1168-1169. PNNL-ACT-SA-10111. doi:10.1126/science.aad5761
  • Gillingham K., W. Nordhaus, D. Anthoff, G.J. Blanford, V. Bosetti, P. Christensen, and H.C. McJeon, et al. 2015. "Modeling Uncertainty in Climate Change: A Multi-Model Comparison." National Bureau of Economic Research. PNNL-SA-112764. doi:10.3386/w21637
  • Iyer G.C., J.A. Edmonds, A.A. Fawcett, N. Hultman, J. Alsalam, G.R. Asrar, and K.V. Calvin, et al. 2015. "The contribution of Paris to limit global warming to 2 °C." Environmental Research Letters 10, no. 12:Article No. 125002. PNNL-SA-111720. doi:10.1088/1748-9326/10/12/125002
  • Iyer G.C., L.E. Clarke, J.A. Edmonds, B.P. Flannery, N. Hultman, H.C. McJeon, and D. Victor. 2015. "Improved Representation of Investment Decisions in Assessments of CO2 Mitigation." Nature Climate Change 5, no. 5:436-440. PNNL-ACT-SA-10042. doi:10.1038/nclimate2553
  • Iyer G.C., L.E. Clarke, J.A. Edmonds, N. Hultman, and H.C. McJeon. 2015. "Long-term payoffs of near-term low-carbon deployment policies." Energy Policy 86. PNNL-ACT-SA-10084. doi:10.1016/j.enpol.2015.08.004
  • Iyer G.C., N. Hultman, J. Eom, H.C. McJeon, P.L. Patel, and L.E. Clarke. 2015. "Diffusion of low-carbon technologies and the feasibility of long-term climate targets." Technological Forecasting and Social Change 90, no. Part A:103-118. PNNL-SA-93434. doi:10.1016/j.techfore.2013.08.025
  • Scott M.J., D.S. Daly, J.E. Hathaway, C.S. Lansing, Y. Liu, H.C. McJeon, and R.H. Moss, et al. 2015. "Calculating Impacts of Energy Standards on Energy Demand in U.S. Buildings with Uncertainty in an Integrated Assessment Model." Energy 90, no. Part 2:1682-1694. PNNL-SA-102017. doi:10.1016/


  • McJeon H.C., J.A. Edmonds, N. Bauer, L.E. Clarke, B. Fisher, B.P. Flannery, and J. Hilaire, et al. 2014. "Limited impact on decadal-scale climate change from increased use of natural gas." Nature 514, no. 7523:482-485. PNNL-ACT-SA-10016. doi:10.1038/nature13837
  • Scott M.J., D.S. Daly, Y. Zhou, J.S. Rice, P.L. Patel, H.C. McJeon, and P. Kyle, et al. 2014. "Evaluating sub-national building-energy efficiency policy options under uncertainty: Efficient sensitivity testing of alternative climate, technolgical, and socioeconomic futures in a regional intergrated-assessment model." Energy Economics 43, no. 2014:22-33. PNNL-SA-92108. doi:10.1016/j.eneco.2014.01.012
  • Wise M.A., H.C. McJeon, K.V. Calvin, L.E. Clarke, and P. Kyle. 2014. "Assessing the interactions among U.S. climate policy, biomass energy, and agricultural trade." The Energy Journal 35, no. Special Issue. PNNL-SA-92917. doi:10.5547/01956574.35.si1.9


  • Lemoine D.M., and H.C. McJeon. 2013. "Trapped Between Two Tails: Trading Off Scientific Uncertainties via Climate Targets." Environmental Research Letters 8, no. 3:Article No. 034019. PNNL-SA-84333. doi:10.1088/1748-9326/8/3/034019

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