Meet Our Team

Our team includes data analysts, scientists, policy experts, and communication pros, offering an extensive skillset to bring cutting-edge analysis to policy research.


Angel Hsu, PhD

Principal Investigator
PhD, Environmental Policy

Angel Hsu, PhD, is an Associate Professor of Public Policy and the Environment, Ecology and Energy Program (E3P) at the University of North Carolina-Chapel Hill and holds a PhD in Environmental Policy from Yale University.

She is the Founder and Principal Investigator of Data-Driven EnviroLab. Angel previously held appointments at Yale-NUS College in Singapore as Assistant Professor of Environmental Studies, and the World Resources Institute (WRI) where she managed and led WRI’s efforts to develop corporate greenhouse gas accounting and reporting initiatives in developing countries, including China. Angel was also the lead author of the 2018 UNEP Emissions Gap report chapter on non-state actors and an author for the IPCC AR6. Angel holds an M Phil in Environmental Policy from the University of Cambridge, and a BS in Biology and BA in Political Science from Wake Forest University in Winston-Salem, NC.

Julia Cardwell

Evan Johnson, PhD

Research Assistant Professor
PhD, Public Policy

Evan Johnson is a Research Assistant Professor of Public Policy at UNC-Chapel Hill. He founded Arclight Analytics, a data science consulting group that provides analysis and data solutions for the government and non-profit organizations. Johnson has previously served as Principal Consultant on multiple Evaluation Panels at the U.S. National Academies of Science, Engineering and Medicine, where he has co-authored reports for Congress to aid in evaluating Public R&D programs for innovation and entrepreneurship. His research focuses on the various interactions among governments, scientists, and entrepreneurs in shaping our innovation landscape, particularly with respect to climate change. Johnson teaches also teaches courses in Quantitative Policy Analysis, Research Design, and Energy Policy and Resources at UNC. He holds master’s and doctoral degrees in public policy from the University of Wisconsin and UNC-Chapel Hill, respectively.

Xuewei Wang

Xuewei Wang

Research Scientist
MS, Natural Resources and the Environment

Xuewei holds an MS in Natural Resources and the Environment from the University of Michigan, where she focused on estimating and mapping sustainable agriculture practices with remote sensing imagery and machine learning. She is interested in conducting natural resources management, addressing environmental challenges, and helping sustainable development through big data and data mining. Xuewei’s professional experience includes building machine learning models for precision agriculture, land-cover-land-use classification, leveraging multispectral optical and radar sensor data on the environment problem-solving, and geospatial data API development. She is an expert in applying remote sensing data to environmental issues and Google Earth Engine, where she is developing a java-script based application for our Urban Environment and Social Inclusion Index.  As a data enthusiast, Xuewei also explores other topics where environmental studies and data science intersects, including data visualization, deep learning, and web development. She loves to capture the beauty of mother nature with her camera.

Diego Manya

Research Associate
MEM, Masters of Environmental Management – Yale

Diego Manya is a Data Scientist and hold a Masters of Environmental Management degree from the Yale School of Environment. He has extensive experience working in environmental management, sustainable development, international cooperation and project implementation, supporting private and public actors in the US, Latin-America and the Caribbean. His focus is in interdisciplinary research and supports multiple initiatives combining data discovery, remote sensing, statistics and machine learning in topics like urbanization, climate change and equity with a particular focus in the Urban Environmental and Social Inclusion Index, a project he helped conceptualize and developed from the pilot stages. He is an Environmental Engineer from the UNALM in Peru and is based in Lima, Peru.

Julia Cardwell

Sarah Berk

Postdoctoral Research Associate
PhD, Climactic Research

Sarah Berk, a Postdoctoral Research Associate at the Data-Driven Lab, earned her PhD from the Climatic Research Unit at the University of East Anglia, UK. Her doctoral thesis concentrated on projecting surface urban heat islands under both current and future climates, employing machine learning techniques combining with satellite, reanalysis, and CMIP6 data. Currently, her research pursuits have shifted towards investigating the canopy urban heat island phenomenon. This includes exploring diverse methodological approaches for its derivation and examining the human impacts of urban heat. With a longstanding interest in data and statistics, Sarah holds a BSc in Mathematics from the University of Exeter and has previously worked as a finance analyst.

Julia Cardwell

Ying Yu

Postdoctoral Research Associate
PhD, Environmental Sciences and Engineering

Ying Yu is a Postdoctoral Research Associate at Data-Driven EnviroLab, with a PhD in Environmental Sciences and Engineering from UNC-Chapel Hill. She has a Bachelor’s degree in Financial Engineering and a Master’s degree in Technology Economy and Management. Her doctoral research tackled climate challenges in energy-vulnerable communities, specifically exploring the climate-energy equity nexus and public perceptions toward renewable energy transitions. Ying’s current research interest lies in leveraging her interdisciplinary expertise in energy economics, data science, and geospatial techniques to devise targeted and differentiated environmental and energy solutions, thus informing policymakers and practitioners with data-driven and evidence-based insights. Her work involves using machine learning and remote sensing techniques to predict high-resolution energy data for data-sparse areas and conducting quantitative policy analysis to enhance urban air quality and support subnational and non-state climate actions. Ying loves backpacking and has been to 30 countries.

Student Research Assistants

Katherine Burley

UNC-Chapel Hill, PhD Student (Public Policy)

Katherine is a graduate research assistant for the Data-Driven Lab, currently pursuing a PhD in Public Policy at the University of North Carolina at Chapel Hill. Her research interests include energy and environmental policy, specifically how subnational governments and electric utilities respond to climate change issues and the ongoing renewable energy transition. Prior to entering the PhD program, Katherine worked in economic consulting. At her most recent role, she evaluated demand-side management programs and technologies for utilities and energy companies throughout North America. She received a BS in Economics from Louisiana State University and an MA in Economics from the University of Texas at Austin.

Julia Cardwell

Daniel Han

UNC-Chapel Hill, PhD Student (Public Policy)

Daniel is a 6th year Public Policy PhD Candidate at the University of North Carolina at Chapel Hill. At DDL, Daniel is working to develop a Fourier method of regression modeling (applied to the lab’s EUCoM emissions data) as part of his dissertation, along with working with Evan to better understand how subnational actors’ self select into energy and environmental policy programs and initiatives. Since our projects are extremely relevant to current climate change impacts and challenges, Daniel is excited to get hands-on experience tackling climate policy problems and creating climate policy solutions.

Julia Cardwell

Izzy Bukovnik

UNC-Chapel Hill, PhD Student (Public Policy)

Izzy is a graduate research assistant for the Data-Driven Lab and a PhD student in the Public Policy Department at the University of North Carolina at Chapel Hill. Her academic interests include the factors that influence non-state actors to enact environmental regulations (particularly the interplay between municipal and state governments), data visualization, and science communication. Izzy has a Masters in Environmental Management with a specialization in Geographic Information Systems from Duke University and a BA in Integrative Biology from the University of California at Berkeley. In her free time, Izzy enjoys hiking with her two dogs, Artemis and Virgil.

Julia Cardwell

Ella Feathers

UNC-Chapel Hill, Master’s Student (Journalism)

Ella Feathers is a student in the Science-Communication dual degree program where she earned Bachelors degrees in Economics and Environmental Studies and is pursuing a Master’s degree in Journalism. At UNC, she served as the Undergraduate Student Government Co-Director of Environmental Affairs for and the student representative to the Town of Chapel Hill Environmental Stewardship Advisory Board. Ella is passionate about finding creative and innovative ways to communicate sustainability actions and solutions.

Julia Cardwell

Christian Chung

Duke, Master’s Student (Public Policy)

Christian is a senior at the University of North Carolina at Chapel Hill studying Public Policy and Biology with a minor in Environmental Science. He is joining DDL to work on a case study on Singapore’s water resource infrastructure and to assist other RAs on data and sensor validation. In his free time, Christian enjoys going to the gym, yoga, and fashion upcycling.

Julia Cardwell

Mason Laney

UNC-Chapel Hill, Master’s Student (Computer Science)

Following completion of his Bachelors degrees in Computer Science and Linguistics with a minor in Data Science, Mason is pursuing his Masters degree in Computer Science at UNC Chapel Hill. He is joining DDL as a Machine Learning / Natural Language Processing research assistant, where he will use his skills to help us create ChatNetZero, the first LLM designed to accurately answer questions about net zero and actors’ net-zero commitments. In his free time, Mason enjoys video games and trading card games.

Julia Cardwell

Alicia Bao

UNC-Chapel Hill ’26

Alicia is a second-year computer science and sociology major working primarily with the Net Zero Tracker. Outside of academics, she advocates for the establishment of Asian American Studies at UNC and enjoys making art, and photography.

Julia Cardwell

Noah Civiletti

UNC-Chapel Hill ’24

Noah is a senior studying Mathematics, Statistics, and Geographic Information Systems (GIS) at the University of North Carolina at Chapel Hill. He is joining DDL as a GIS Analyst Student Research Assistant for the 2023-2024 academic year. Previously, Noah has modeled urban heat island effects and identified optimal green space locations in Chapel Hill and Durham. He is excited to further develop skills that blend mathematics, data, geography, and environmental issues. Outside of academics, Noah enjoys exercising, learning languages, and advocating for better urbanism. 

Julia Cardwell

Emma Holmes

UNC-Chapel Hill ’24

Emma is a senior at the University of North Carolina at Chapel Hill majoring in Global Studies with minors in Geography and Geographic Information Systems (GIS). She is joining DDL for the 2023-2024 academic year as a GIS Analyst Student Research Assistant. She is excited to develop stronger GIS and programming skills while working on projects that combine her passions for geospatial analysis, public policy, and sustainability. Outside of academics, Emma enjoys learning new hobbies, reading fantasy novels, and being a barista.

Julia Cardwell

Sarah Combs

Social Connectedness Fellow

Sarah is a recent UNC graduate with Bachelor’s degree in Environmental Health Science. Joining DDL as a fellow in partnership with the Samuel Centre for Social Connectedness, she is excited to participate in an impactful project that can generate a positive community impact. Beyond her work, Sarah enjoys cross-stitching and ultimate frisbee.

Julia Cardwell

Ming Cheng

Yale-NUS ’26

Ming Cheng is an Economics major at Yale-NUS College and pursuing a Masters in Public Health at Yale University. His academic interests include energy and environmental policy, and its intersection with public health. In his free time, Ming Cheng enjoys going to the gym and all things dance.


TC Chakraborty

PhD, Earth and Environmental Sciences

TC completed his PhD at the Yale School of Forestry and Environmental Studies and is currently a Research Scientist at Pacific Northwest National Laboratory. He has a B.Tech in Civil Engineering and an M.Tech in Environmental Engineering and Management. During his Master’s thesis, he quantified the temporal and spatial aspects of the canopy and surface urban heat islands of the greater Kanpur region using in-situ measurements, mobile campaigns, and remote sensing. He currently investigates how the exchange of energy between the surface and the atmosphere influences local weather and climate. In particular, he is interested in the influence of highly heterogeneous terrain, like urban areas, on boundary layer dynamics. His work involves running numerical weather prediction models, analyzing climate data, and satellite remote sensing.

Brendan Mapes

Marco Schletz, PhD

Post-doctoral Research Associate
PhD, Innovation and Environmental Studies

Marco holds a PhD in Innovation and Environmental Studies from the Technical University of Denmark (DTU) where worked with the UNEP DTU Partnership researching how blockchain technology can accelerate the implementation of the Paris Agreement and the Sustainable Development Goals. More specifically, he explored blockchain as a foundational technology to enable innovative governance models, specifically towards the new Paris Agreement carbon market mechanisms. Marco has experience developing national accounting systems through the Initiative for Climate Action Transparency (ICAT) and the Capacity Building Initiative for Transparency (CBIT). Additionally, he has managed climate finance projects under the ADMIRE project with external partners across the broader international community in the context of the Paris Agreement. He also holds a Master’s degree in Environmental Science from the University of Copenhagen and is certified in blockchain business innovation and application through MIT Sloan Executive Education.