Naoko Sakaeda, Ph.D.
Associate Professor
School of Meteorology
University of Oklahoma
Norman, Oklahoma, USA
Email: nsakaeda@ou.edu
Curriculum Vitae
Google Scholar Profile
Research Gate Profile
ResearcherID Profile
Short Bio:
Dr. Sakaeda received Ph. D in atmospheric sciences at University at Albany, SUNY in Albany, New York and a Bachelor of Science at the University of Washington in Seattle, Washington. Prior to joining the School of Meteorology as a faculty, she was a National Research Council postdoctoral associate at NOAA/ESRL in Boulder Colorado. Dr. Sakaeda grew up in southeast Asia, which led to her interest in tropical meteorology. Her research interests include understanding the dynamics of tropical clouds and precipitation in various scales and their interactions with higher latitudes.
Hrag Najarian
Ph. D. Student
Hrag joined the Sakaeda Research group in the Fall of 2019. He was born in Lebanon but then moved to Los Angeles at the age of 5. Soon after, he became fascinated by the weatherman’s ability to predict the future which sparked a passion that grew out of hand. He completed his B.S. in Atmospheric Sciences at the University of California, Davis in the Summer of 2018, and then his M.S. in Meteorology at the University of Oklahoma in the Fall of 2021, studying cloud-radiative effects within the Madden-Julian Oscillation. He is now pursuing his Ph.D. working alongside Dr. James Ruppert and Dr. Naoko Sakaeda to continue to understand cloud-radiative interactions on a diurnal time scale within the seasonal-to-subseasonal timescale over the Maritime Continent through numerical modeling.
Email: hrag.najarian@ou.edu
Sadiksha Rai
Ph.D. Student
Sadiksha joined the Sakaeda Research Group in August 2019 and is studying the Madden Julian Oscillation (MJO) with her main focus on the relationship between tropical stratospheric oscillation called Quasi Biennial Oscillation (QBO) and MJO. She was born and raised in Nepal and completed her B.Sc. Meteorology in 2017 from Tri-Chandra Multiple Campus, the only college providing meteorology course at the undergraduate level in Nepal. She completed her two semesters for graduate-level in the Central Department of Hydrology and Meteorology, Kathmandu, Nepal and then made her path to the University of Oklahoma. In her childhood, she used to be very curious about different weather and climatological phenomena and shapes of clouds used to interest her a lot. Surely, it’s her interest that drives her all the way from Nepal to the US to broaden her knowledge about meteorology and different dynamics related to it.
Email: sadi05@ou.edu
Sadiksha’s CV
TATIANA ESTEVA-INGRAM
Ph.D. Student
Tatiana joined the Sakaeda Research Group in August 2021 and is studying the Madden-Julian Oscillation (MJO) with focus on the seasonality of the MJO teleconnections. After spending most of her life in Sparta, New Jersey, she attended the University of Louisiana-Monroe where she obtained her B.S. in Atmospheric Sciences along with a minor in Mathematics in 3 years. When presenting her REU research at the Annual American Meteorological Society Meeting in 2021, she won best undergraduate poster in the Atmospheric Electricity session. Her interest in the weather started at an early age but living through Hurricane Sandy and taking a tropical class in college is where the interest in tropical-extratropical interactions began to bloom.
Email: tatiana.nei1@ou.edu
Wayne (Yuan-huai) tsai
Ph.D. Student
Wayne joined the Sakaeda Research Group in the fall of 2023. He was born and raised in Taiwan. Wayne completed his B.S. in Earth Sciences at National Taiwan Normal University and his M.S. in Atmospheric Sciences at National Taiwan University. His interest in tropical climates was sparked during his master’s research, where he studied how tropical waves influence rainfall extremes on subseasonal timescales, evaluating their predictability in the subseasonal-to-seasonal (S2S) prediction models. Currently, he is pursuing his Ph.D. and working with Prof. Naoko Sakaeda and Prof. James Ruppert. His research primarily explores how the Madden-Julian Oscillation (MJO) modulates diurnal processes over tropical islands, while also assessing the ability of S2S prediction models to capture these characteristics.
E-mail: wayne.yhtsai@ou.edu
Wayne’s Curriculum Vitae
Jessica Davis
Master’s Student
Jessica joined the Sakaeda Research Group and the University of Oklahoma’s School of Meteorology in August 2024. She has been working assessing tropical-extratropical interactions associated with convectively coupled equatorial waves. Jessica graduated from Michigan State University with a dual major Bachelors of Science in Geographic Information Science, and Environmental Geography Concentrated in Atmospheric and Climate Sciences, along with a minor in Social Science Quantitative Data Analytics. During her undergraduate studies, Jessica worked with the State Climatologist for Michigan Dr. Jeffrey Andresen to update the Michigan Hazard Analysis Index. Jessica is particularly interested in topics including but certainly not limited to climate variability, interactions, and impacts.
Email: jessica.r.davis-2@ou.edu
Jessica’s CV
Shu-Hsuan Lin
PhD Student
Shu-Hsuan joined the Sakaeda research group in Fall 2024. She earned her B.S in Earth Sciences from National Taiwan Normal University and her M.S in Atmospheric Physics from National Central University. From 2022 to 2024, She worked as a research assistant at Academia Sinica, Taiwan, where she explored climate model simulations. Currently, she is now pursuing her Ph.D. with Professor Naoko Sakaeda, focusing on the role of cloud-radiative feedback as the coupling mechanisms of the Madden Julian Oscillation (MJO) and the Quasi-Biennial Oscillation (QBO). Her primary research interests lie in tropical meteorology, examining the nature of tropical systems through various lenses, including observational data, climate models, and machine learning.
Email: shuhsuan.lin-1@ou.edu
Shu-Hsuan’s Website
Isabelle Jernigan
PhD Student
Isabelle joined the Sakaeda Research Group in August 2025. She is originally from South Carolina, and earned her B.S. in Meteorology and Atmospheric Sciences from Penn State with minors in Math and Geographic Information Systems (GIS). As an undergraduate, she conducted research on intrinsic tornado predictability with Dr. Paul Markowski. Isabelle went on to complete her M.S. in Meteorology at the University of Oklahoma in Summer 2025, where she investigated tornadic supercell evolution in the extreme environment of the 27 April 2011 super outbreak under the supervision of Drs. Tony Lyza and Matt Flournoy. Now pursuing a Ph.D., Isabelle has shifted her focus to tropical meteorology, with current research centered on the coastal environment and mesoscale convective systems (MCSs) in the West Africa region.
Julian Moreno
Undergraduate Research Assistant
Alumni
Shun-Nan Wu: 2020-2025 Postdoc and Research Scientist. Currently an assistant professor at the University of Kansas. website
Jacob Hamil: 2024 REU Student from the University of Georgia. Project: Madden-Julian Oscillation (MJO) Teleconnections and their Impact on Precipitation in South America (NWC REU 2024)
Sonny Krennin: 2024 REU Student from the St. Cloud State University. Project: A Case Study of Mesoscale Convective System Reorganization off of the West Coast of Africa (NWC REU 2024)
Theresa Lincheck: Completed Master’s degree in August 2024. Thesis: Evolution of Observed Cloud Organization within Tropical Rainfall Events during the DYNAMO/AMIE Field Campaign
Patrick Thornton: 2023 REU student from the North Carolina State University. Project: Connecting African Easterly Wave development and offshore precipitation (NWC REU 2023)
Kevin Martinez-Lopez: 2022 REU student from the University of Puerto Rico at Mayagüez, Project: Factors Affecting Precipitation over Western Puerto Rico during the NASA 2021 CPEX-AW Project. (NWC REU 2022)
Stephen Foskey: Completed Master’s degree in Aug 2022, Thesis: The Impact of the Madden-Julian Oscillation on Extreme Winter Weather over the Contiguous United States.
Andrew Berrington: Completed Master’s degree in Dec 2020, Thesis: Relationships between the Circulation and Eastward Propagation of the Madden-Julian Oscillation.
Leanne Blind-Doskocil: 2019 REU student from Texas A&M University, Project: Evolution of the Diurnal Cycle of Tropical Rainfall associated with the Madden-Julian Oscillation (a summary of her work is available here).