Yunjiao Pu, Ph.D.
Associate Professor
Office: Academic Building II-B1-217
Email: yunjiao.pu@nju.edu.cn
RESEARCH INTEREST
Atmospheric Electricity; Lightning; High-energy atmospheric physics; Ionospheric physics
BIO
Dr. Pu is an atmospheric physicist specializing in atmospheric and space electricity. Since 2018, she has been leading radio observations of lightning at Duke University. She served as a ground mission scientist for the 2023 ALOFT campaign, a collaborative effort between NASA and the University of Bergen focused on airborne observations of high-energy radiation emanating from thunderstorms. Her research extends to developing state-of-the-art atmosphere radio remote sensing techniques spanning from very low frequencies to very high frequencies. Her work revolves around the physics of lightning discharge, its associated impact on the environment, and the Earth’s electrical environment in general.
The Atmospheric Electricity Laboratory is accepting applications for Master's, PhD, and Postdoctoral positions. Students with backgrounds in atmospheric science, electrical engineering, physics, and related fields are welcome to inquire.
EDUCATION
Ph.D. in Electrical and Computer Engineering, Duke University, 2022
M.S. in Atmospheric Physics, University of Chinese Academy of Sciences, 2018
B.S. in Atmospheric Sciences, Nanjing University, 2015
POSITIONS
Tenure-track Associate Professor, Nanjing University, 2025 -
Research Scientist, Duke University, 2024 - 2025
Postdoctoral Associate, Duke University, 2022 - 2023
AWARDS AND HONORS
AGU Outstanding Reviewer Citation (JGR: Atmospheres) 2023
International Union of Radio Science (URSI) Young Scientist Awardee 2023
AGU Fall Meeting Outstanding Student Presentation Award (OSPA) 2021
Duke University Kristina Johnson Award 2021
Distinct Graduates of Beijing City 2018
National Scholarship for Graduate Students 2017
National Scholarship for Undergraduate Students 2013
COURSES TAUGHT
Graduate Courses: Advanced Atmospheric Sciences, English Course for NHI Master's Students
Undergraduate Courses: Atmospheric Science Experiments and Field Methods, English Course for Bachelor's Students
Dec 7, 2022 and Nov 23, 2023 | Nanjing University, guest lecture titled “Introduction to Atmospheric Electricity” in the undergraduate class Chasing the Mystery of Atmospheric Sciences.
2019 Fall and 2021 Spring | Duke ECE270DL Waves and Fields, teaching assistant and lecturer for both lab experiments and lectures.
SUPERVISION OF STUDENTS
Current lab members:
Chunan Zhang (2025 - ), research assistant, thunderstorm high-energy radiation and cloud microphysics
Shixian Yin (2025 - ), undergraduate, lightning imaging and simulation
Hongtao Li (2025 - ), undergraduate, hardware design for lightning and meterology studies
Before Summer 2025:
Spring 2023 – Spring 2025 | Zeck J*, from Duke ECE, project on radio remote sensing of the lower ionosphere.
Fall 2022 – Spring 2023 | Anya T*, from North Carolina School of Science and Math, project on numerical simulation of lightning radio interferometry.
Summer 2022 | Santosh K*, from North Carolina School of Science and Math, project on machine learning of lightning radio signals.
Spring 2022 | Braeden W*, undergraduate of Duke University, project on laboratory measurement of radio frequency devices.
Summer 2019 | Joshua F*, from East Chapel Hill High School, project on electromagnetic and optical measurements of laboratory spark discharge.
SERVICE
Member, AGU Atmospheric and Space Electricity Section Fellows Review Committee, 2023 - 2024
Primary convener and Co-chair, Session AE002 “Advances in Instrumentation and Signal and Data Processing Methods for Atmospheric Electricity Applications”, American Geophysical Union (AGU) Fall Meeting, New Orleans, USA, 2025
Co-convener and Co-chair, Session AE002 “Advances in Instrumentation and Signal and Data Processing Methods for Atmospheric Electricity Applications”, AGU Fall Meeting, USA, 2023 - 2024
Co-Chair, 2nd Internation Symposium on Lightning Physics and Lightning Meteorology (ISLPM), Beijing, China, 2025
Host of American Geophysical Union Atmospheric and Space Electricity Early Career Seminar Series, 2023 - 2024
Reviewer, Science, Science Advances, Geophysical Research Letters, Journal of Geophysical Research, Atmospheric Research, Journal of Atmospheric and Solar Terrestrial Physics, Remote Sensing, etc
Evaluator, National Science Foundation, USA, 2025 -
Member, American Geophysical Union (AGU), 2017 -
SELECTED PUBLICATIONS
I am a co-author of 25 refereed publications in journals including Nature, Geophysical Research Letters, and Journal of Geophysical Research-Atmospheres, 11 of which are as first or corresponding author*. Full records are available on Google Scholar.
Pu,Y.*, Cummer,S. A.*, & Jia,Y. (2025). Continental-scale lightning observations at high frequency. Geophysical Research Letters, 52, e2025GL116075. https://doi.org/10.1029/2025GL116075
Studying lightning processes over long distances is challenging because lightning-emitted radio waves weaken as they travel over the ground. A new approach is demonstrated to use high-frequency (HF, 3–30 MHz) radio emissions reflected by the ionosphere to study lightning remotely and improve long-distance storm monitoring.
Pu, Y., and S. A. Cummer (2019), Needles and Lightning Leader Dynamics Imaged with 100–200 MHz Broadband VHF Interferometry, Geophysical Research Letters, 46, 13556–13563. https://doi.org/10.1029/2019GL085635
I improved a broadband VHF lightning interferometer to image detailed lightning processes inside the cloud with high spatial and time resolution. This enables the discovery of needle-to-negative leader transition and other lightning development dynamics that were not readily detectable in the past.
Pu, Y.*, & Cummer, S. A*. (2024). Continuous initial breakdown development of in‐cloud lightning flashes. Journal of Geophysical Research: Atmospheres, 129(20), e2024JD041302. https://doi.org/10.1029/2024JD041302 (Eos Editor’s Highlight)
Pu, Y., & Cummer, S. A. (2024). Imaging step formation in in‐cloud lightning initial development with VHF interferometry. Geophysical Research Letters, 51(1), e2023GL107388. https://doi.org/10.1029/2023GL107388
How lightning propagates in the first few milliseconds has long been a mystery. Utilizing state-of-the-art lightning imaging with a 30-250 MHz VHF interferometer, the above two papers provide clear images of the detailed processes during initial development of in-cloud lightning flashes.
Pu, Y., N. Y. Liu and S. A. Cummer, (2022), Quantification of Electric Fields in Fast Breakdown during Lightning Initiation from VHF-UHF Power Spectra, Geophysical Research Letters, 49, e2021GL097374. https://doi.org/10.1029/2021GL097374
Pu, Y., S. A. Cummer, and N. Y. Liu (2021), VHF Radio Spectrum of a Positive Leader and Implications for Electric Fields, Geophysical Research Letters, 48, e2021GL093145. https://doi.org/10.1029/2021GL093145
In-situ measurements of lightning at precise times and locations are nearly impossible. The above two papers propose novel VHF-UHF radio spectral techniques that indirectly measure electric fields in the precise regions where lightning begins/propagates.
Pu, Y., S. A. Cummer, F. C. Lyu, M. Briggs, B. Mailyan, M. Stanbro, and O. Roberts (2019), Low Frequency Radio Pulses Produced by Terrestrial Gamma-Ray Flashes, Geophysical Research Letters, 46, 6990–6997. https://doi.org/10.1029/2019GL082743
A statistical study between TGF and lightning radio signals is conducted to study TGF-lightning connection. The connection between TGF and a low frequency slow-pulse during lightning development has been confirmed.
Pu, Y., S. A. Cummer, A. Huang, M. Briggs, B. Mailyan, and S. Lesage (2020), A Satellite-Detected Terrestrial Gamma Ray Flash Produced by a Cloud-to-Ground Lightning Leader, Geophysical Research Letters, 47, e2020GL089427. https://doi.org/10.1029/2020GL089427
Built upon the slow-pulse-TGF connection, I discovered likely a new type of reverse TGF produced by a cloud-to-ground lightning leader.
Pu, Y., Cummer, S. A., Lyu, F., Zheng, Y., Briggs, M. S., Lesage, S., et al. (2023). Unsupervised clustering and supervised machine learning for lightning classification: Application to identifying EIPs for ground-based TGF detection. Journal of Geophysical Research: Atmospheres, 128, e2022JD038369. https://doi.org/10.1029/2022JD038369
I designed a machine learning framework to distinguish various lightning radio signals. This enables large-scale ground-based TGF detection using a proxy signature named EIPs, which in turn would improve our understanding of TGF generation.
Pu, Y., X. S. Qie, R. B. Jiang, Z. L. Sun, M. Y. Liu, and H. B. Zhang (2019), Broadband Characteristics of Chaotic Pulse Trains Associated with Sequential Dart Leaders in a Rocket-Triggered Lightning Flash, Journal of Geophysical Research-Atmospheres, 124, 4074–4085. https://doi.org/10.1029/2018JD029488
Pu, Y., R. Jiang, X. Qie, M. Liu, H. Zhang, Y. Fan, and X. Wu (2017), Upward negative leaders in positive triggered lightning: Stepping and branching in the initial stage, Geophysical Research Letters, 44, 7029–7035, https://doi.org/10.1002/2017GL074228
Rocket triggered lightning is useful to study detailed lightning physics due to its known occurrence. The above two papers reveal optical and broadband radio characteristics of both upward and downward negative lightning leaders.
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