- Expertise on national climate strategies and policies, assessments of national ambition in the U.S., China and other major economies, fossil phaseout strategies, and subnational climate action
- Served in the Office of Special Presidential Envoy for Climate in the U.S. State Department; and in the Obama White House. Contributed to U.S. Long Term Strategy, U.S-China Joint Glasgow Declaration, U.S. 2025 NDC
- Founded and directs the Center for Global Sustainability, which links collaborative research with policy engagement to support enhanced global climate ambition and action
Nate Hultman is the Founder and Director of the Center for Global Sustainability at the University of Maryland, and Professor in the School of Public Policy. Prof. Hultman’s work focuses on developing and assessing policy strategies to target and achieve ambitious national climate goals. This includes U.S. emissions mitigation policy, rapid coal phaseout strategies in diverse national contexts, and economy-wide emissions strategies in key countries, with a focus on China and others. He was recently Senior Advisor in the Office of the Special Presidential Envoy for Climate at the U.S. Department of State, where he led the writing of the 2021 U.S. Long Term Strategy report and helped negotiate the U.S.-China Joint Glasgow Declaration at COP26. In his academic research, he was also lead author of several recent assessments of U.S. national climate strategies and emissions targets in advance of the announcement of the U.S. 2030 climate target (NDC). From 2014-2016, Hultman worked at the White House on the Obama Administration’s climate and energy policy team. During this time, he helped develop the U.S. 2025 NDC, supported bilateral engagements with China and others, and participated in the international climate negotiations in Paris. He has participated in the UN climate process for 25 years, starting with the Kyoto meeting. Hultman is also a nonresident senior fellow at the Brookings Institution, and associate director of the Joint Global Change Research Institute, a collaboration between the University of Maryland and the Pacific Northwest National Laboratory. He was formerly a visiting fellow at the University of Oxford and a Fulbright fellow. He holds an M.S. and Ph.D. in Energy & Resources from the University of California, Berkeley, and a B.A. in Physics from Carleton College.
- Climate change; energy policy; US federal climate policy

After the U.S. withdrew from the Paris Agreement in 2017, CGS led the analysis of commitments from the more than 4,000 cities, states, businesses, universities, communities of faith, and more who pledged to support the goals of the Paris Agreement in their own capacity. Since the U.S. officially rejoined the Paris Agreement in March 2021, CGS has continued working with U.S. subnational and international partners to deliver analysis that informs how an "all-of-society" ambitious and achievable U.S. climate strategy can drive actionable and feasible policy. CGS informs U.S. climate policy from the local to global through developing integrated modeling and climate scenarios for the federal government, advising on international discussions to ramp up ambition, and collaborating from the bottom-up to move the resources necessary to set and achieve ambitious climate goals.
Learn More about Building a Comprehensive U.S. Climate Policy
Through our research on the state of global coal, CGS conducts analysis on the trends of global coal power -- leveraging and building on new global datasets to paint a global and country-specific picture of coal power worldwide.
Learn More about Program to Accelerate the Global Coal Transition
Our work at CGS builds a model integrating engagement, analysis, and multi-level governance that can provide the driving force for enhanced ambition.
Learn More about Analytics for Global Climate Ambition
The China Program at CGS integrates scientific research, education, policy analysis, and stakeholder engagement to help understand and inform the development and deployment of China’s climate, energy, and environment strategies across international, national, and local contexts.
Learn More about China ProgramSchool Authors: Alicia Zhao, Haewon McJeon, Yiyun 'Ryna' Cui, Gokul Iyer, Kathleen Kennedy, Shannon Kennedy, Nathan Hultman
Other Authors: Tom Cyrs, John Feldmann, Kevin Kennedy, Kowan O'Keefe (CGS PhD Candidate), Sujata Rajpurohit, Lainie Rowland
School Authors: Yiyun 'Ryna' Cui, Jiawei Song, Nathan Hultman
Other Authors: Xueqin Cui, Diyang Cui, Xiaoli Zhang, Fan Dai, Jessica Gordon, Zhinan Chen, Daniel Kammen
School Authors: Morgan Edwards, Yiyun 'Ryna' Cui, Nathan Hultman, Haewon McJeon, Gokul Iyer, Jiawei Song, Alicia Zhao
Other Authors: Matilyn Bindl, Krinjal Mathur
School Authors: Mengye Zhu, Leon Clarke, Nathan Hultman
Other Authors: Vaibhav Chaturvedi
School Authors: Gokul Iyer, Leon Clarke, James 'Jae' Edmonds, Nathan Hultman, Yiyun 'Ryna' Cui, Sha Yu, Haewon McJeon
Other Authors: Yang Ou, Allen A. Fawcett, James R. McFarland, Matthew Binsted, Claire Fyson, Andreas Geiges, Sofia Gonzales-Zuñiga, Matthew J. Gidden, Niklas Höhne, Louise Jeffery, Takeshi Kuramochi, Jared Lewis, Malte Meinshausen, Zebedee Nicholls, Pralit Patel, Shaun Ragnauth, Joeri Rogel J., Stephanie Waldhoff
School Authors: Yiyun 'Ryna' Cui, Leon Clarke, Nathan Hultman, Shannon Kennedy
Other Authors: Diyang Cui, Camryn Dahl, Claire Squire
School Authors: Yiyun 'Ryna' Cui, Nathan Hultman, Haewon McJeon, Leon Clarke
School Authors: Nathan Hultman, Leon Clarke, Haewon McJeon, Alicia Zhao, Yiyun 'Ryna' Cui, Shannon Kennedy
Other Authors: Kevin Kennedy, Wendy Jaglom, Erin Bridgwater, Randall Mendell, Haley Leslie-Bole, Lanie Rowland, Emily McGlynn, Tansy Massey-Green, Tom Cyrs, John O'Neill, Rebecca Gasper, John Feldmann, Kowan O'Keefe
School Authors: Nathan Hultman
School Authors: Haewon McJeon, Nathan Hultman, Leon Clarke
School Authors: Morgan Edwards, Yiyun 'Ryna' Cui, Nathan Hultman, Haewon McJeon, Gokul Iyer, Jiawei Song, Alicia Zhao
School Authors: Nathan Hultman
School Authors: Yiyun 'Ryna' Cui, Nathan Hultman
School Authors: Kavita Surana, Leon Clarke, Nathan Hultman
Other Authors: Niamh McCarthy, Dame Karen Pierce, Claire Langley, Nigel Purvis
School Authors: Nathan Hultman, Leon Clarke, Haewon McJeon, Yiyun 'Ryna' Cui, Shannon Kennedy, Alicia Zhao, Jenna Behrendt
Other Authors: John O'Neill, Nathan Hultman, Leon Clarke, Haewon McJeon , Yiyun 'Ryna' Cui, Shannon Kennedy, Alicia Zhao, Jenna Behrendt
School Authors: Nathan Hultman
School Authors: Nathan Hultman, Leon Clarke, Haewon McJeon, Alicia Zhao, Jenna Behrendt, Yiyun 'Ryna' Cui
Other Authors: Kevin Kennedy, Tom Cyrs, John O'Neill, Wendy Jaglom , John Feldmann, Kowan O'Keefe
School Authors: Nathan Hultman
Other Authors: Sander Chan, Idil Boran , Harro van Asselt, Paula Ellinger, Miriam Garcia, Thomas Hale, Lukas Hermwille, Kennedy Liti Mbeva, Ayşem Mert, Charles B. Roger, Amy Weinfurter, Oscar Widerberg, Paulette Bynoe, Victoria Chengo, Ayman Cherkaoui, Todd Edwards, Malin Gütschow, Angel Hsu, David Levaï, Saffran Mihnar, Sara Posa, Mark Roelfsema, Bryce Rudyk, Michelle Scobie, Manish Kumar Shrivastava
School Authors: Nathan Hultman
School Authors: Yiyun 'Ryna' Cui, Nathan Hultman, Haewon McJeon, Sha Yu, Morgan Edwards, Christina Bowman, Leon Clarke, Jiehong Lou, Mengye Zhu
Other Authors: Diyang Cui, Arijit Sen, Kaihui Song, Junjie Kang, Fuqiang Yang, Jiahai Yuan, Weirong Zhang



















