Prof. Dr. Claudia I. Czimczik
Dr. Czimczik received her undergraduate and graduate education in Germany. She obtained a Diplom in Geoecology from the University of Bayreuth (1999) and a doctorate (Dr. rer. nat.) from the Max-Planck-Institute for Biogeochemistry and Friedrich-Schiller-University (2003) in Jena. She joined UCI’s Department of Earth System Science (ESS) as a researcher in 2003, and the faculty in 2011.
Current Graduate Students
Yuan Liu joined the group in 2024. He is interested in understanding the key processes and feedbacks that drive soil carbon dynamics and CO₂ emissions in permafrost systems, and how wildfire and climate change influence these dynamics and potentially accelerate permafrost thaw and greenhouse gas release. He graduated from the University of California, Irvine with a B.S. in both Chemistry and Earth System Science. During his undergrad, he conducted research on the biogeochemical effects of habitat restoration, specifically examining how the restoration of coastal sage scrub ecosystems influences soil carbon and nitrogen cycling. Additionally, he worked as an undergraduate lab assistant for KCCAMS facility, where he developed and obtained a strong foundation in radiocarbon measurement techniques and gained hands-on experience with sample preparation and analysis.
Lurui Niu joined the group in 2023. She graduated from the University of California, Irvine with B.S. in Earth System Science and Biological Science. During her undergrad, she aimed to investigate the source appointment of aerosols in Canada’s tar sand region. Then, she earned a master’s degree in Biogeochemistry and Pollutant dynamics from ETHz, Switzerland. At ETHz, she primarily assisted with the geoscience group and handed on the latest instrument for radiocarbon measurements: MICADAS. Now at UCI, Lurui is interested in aerosol studies from many aspects: 1) isotope-based source appointment of aerosol; 2) how sustainable aviation fuels and advanced jet engines are changing the microphysical properties of aerosols.
Allison Welch joined in 2020 with a broad interest in studying how biogeochemical cycles and other aspects of terrestrial landscapes are changing in response to climate change and other disturbances. She graduated from the University of Florida with a B.S. in Environmental Science with minors in Geology and Wildlife Ecology. During her undergrad, she primarily assisted with paleoclimate research with a focus in geochemistry of fossil corals. She worked on many other projects that spanned applied wildlife management and conservation genetics. Allison’s research explores the implications of shrub expansion into Arctic graminoid tundra systems. She is co-advised by Drs. Claudia Czimczik and Alex Guenther.
Current Postdoctoral Researchers | Specialists
Melissa Schwab joined the group in 2024. She received her doctorate in biogeochemistry from ETH Zurich in 2021. Her research focuses on carbon cycling across riverine and marine systems, with particular interest in how climate-driven processes influence the mobilization, transformation, and export of organic carbon. She combines radiocarbon dating, biomarker analysis, and remote sensing to quantify source-to-sink dynamics, and has worked extensively in Arctic and temperate environments. Her work also incorporates geospatial modeling, machine learning, and Bayesian statistical approaches to constrain carbon fluxes and improve predictive understanding of biogeochemical responses to environmental change.
Current Undergraduate Students
Ian Bachant
Nicole Nielsen
Dhvani Patel
Cecilia Del Rivo
We are STEM majors, incl. chemists, biologists, and geo-, earth, and environmental scientists. If you are interested in joining us, please contact us at czimczik@uci.edu. We are always looking for talented UCI undergraduates (e.g. EarthSS199), future graduate students, and postdocs!
Former Group Members
Postdoctoral Researchers
Shawn Pedron; now at Pattern AG (spedron@uci.edu)
Sandra Holden (NOAA Climate and Global Change Fellow); now at Stanford University (sandra.holden@stanford.edu)
Max (Massimo) Lupascu; now at National University of Singapore (mlupascu@nus.edu.sg)
Simon Fahrni (KCCAMS Postdoc Fellow), now at Ionplus AG (fahrni@ionplus.ch)
Graduate Students
Cindy Yañez (PhD 2023), now at California Air Resources Board (CARB)
Audrey Odwuor (PhD 2021), now at California Air Resources Board (CARB)
Shawn Pedron (PhD 2021), now at Pattern AG
Blanca Rodríguez (PhD 2021), now at South Coast Air Quality Management District
Clayton Elder (PhD 2017), now at NASA AMES (clayton.d.elder@nasa.gov)
Gergana Mouteva (PhD 2016), now at Blue Origin
Recent Undergraduate Students
Dennis Melka
Jazmin RomeroYuan Liu (B.S. Earth System Science & Chemistry, 2024)
Julia Brestyansky (B.S. Earth System Science, 2024)
Angelu Lesaca (B.S. Earth System Science, 2024)
Giselle Jimenez (B.S. Earth System Science, 2023)
Yezzen Khazindar (B.S. Earth System Science, 2022)
Lurui Niu (B.S. Earth System Science & Biological Sciences, 2020)
Brittney Martinez (B.A. Social Ecology with a Minor in Earth and Atmospheric Science, 2020)
Hao Han (B.S. Earth System Science, 2020)
Malissa Tayo (B.S. Earth System Science with a Minor in Global Sustainability, 2020)
Carla Mendez (B.S. Earth System Science with a Minor in Global Sustainability, 2018)
Tiffany Nguygen (B.S. Earth System Science, 2018)
Matthew Schweiger (B.S. Earth System Science with a Minor in Biomedical Engineering, 2018)
Junior G. Mazariegos (B.S. Earth System Science, 2015)
Jaenna Wessling (B.S. Earth System Science, 2015)
Grace Mortero (B.S. Earth System Science, 2015)