Research Interest
Watershed Hydrologic Scientist with 10+ years of experience in hydrologic and ecohydrological modeling, focusing on watershed processes, climate impacts, and water quality dynamics. My work integrates AI/ML and agent-based modeling to simulate human decision-making and characterize model uncertainty, informing sustainable water and environmental management. Skilled in model development, validation, uncertainty analysis, and environmental data collection, I lead projects that advance actionable solutions for water and ecosystem challenges.
SUMMARY OF QUALIFICATIONS
- Strong expertise in hydrologic science, soil science, plant physiology, and water quality
- Extensive experience in distributed ecohydrological modeling, sediment yield modeling, watershed and stream biogeochemistry modeling, including model parameterization, evaluation, and uncertainty analysis
- Skilled in climate change and land-use impact analysis
- Proficient in GIS and remote sensing applications for urban and forest management
- Experienced in AI/ML methods and agent-based modeling for environmental systems
- Expertise in hydropower and water resources modeling
- Proven ability in environmental data collection, including field sampling design and advanced data analysis
Education
- 2015 Ph.D. in the Environmental Science and Management at the University of California, Santa Barbara
- 2008 M.S. in the Geography at the Buffalo University
- 2006 M.S. in the Environmental System Engineering at the University of Western Australia
- 2003 B.SE. in the Environmental Engineering at the Pusan National University
Employment History
- 2019-Current Earth Scientist at the PNNL
- 2019-2019 Postdoctoral Research Fellow at the Lehigh University
- 2015-2019 Postdoctoral Research Fellow at the Research Foundation of CUNY and NYC DEP
- 2005-2007 Research Hydrologist at the Korea Institute of Water and Environment
Publications
JOURNAL PAPERS In Preparation
- Jang, CL., Son, K. Experimental investigation of the effects of vegetation on morphodynamics and sediment sorting processes in a large-scale outdoor laboratory
- Son, K and Tague, C Importance of soil parameter uncertainty in assessing climate change projections in small two Sierra Nevada watersheds, Journal of hydrology
- Son, K et al., Planting or Prevented Planting? Machine Learning Insights Into Farmer Decision-Making.
- Son, K et al., A Machine Learning–Guided Agent-Based Model for Simulating Prevented Planting.
- Son, K et al., Reservoir Operation Flexibility in Hydropower Production During Extreme Events.
- Son K. et al., “A Diagnostic Investigation of the Uncertainty Cascade: How Meteorological Forcing Shapes Hydrologic Model Performance, Parameterization, and Sensitivity”
Submitted Journal Papers
- Garayburu-Caruso V.A., M. Kaufman, B.K. Forbes, X. Lin, B. Hall, S.G. Fulton, and L. Renteria, et al. “Sediment-associated processes drive spatial variation in ecosystem respiration in the Yakima River basin.” Nature Communications Earth & Environment
- Danczak R.E., V.A. Garayburu-Caruso, L. Renteria, O.C. Otenburg, K. Son, M. Kaufman, and M.E. Barnes, et al. 2025. “Non-random processes impacting organic matter chemistry are maximized in mid-order streams.” Science Advances. PNNL-SA-213097.
- Son K., T.K. Tesfa, and V.C. Tidwell. 2026. “Retail Bottled Water Sales Behavior Under Extreme Events.” Earth’s Future
PUBLISHED JOURNAL PAPERS
- Jang, C.L., Shimizu, Y. and Son, K.., 2025. Impact of Mixed Grain Size Sediment Input on Braided River Morphodynamics: Insights from Experimental and Numerical Modeling. KSCE Journal of Civil Engineering, p.100288.
- Regier, P., Chen, Y., Son, K.., Bao, J., Forbes, B., Goldman, A.E., Kaufman, M., Rod, K. and Stegen, J.C., Different Methods of Estimating Riverbed Sediment Grain Size Diverge at the Basin Scale. Frontiers in Earth Science, 13, p.1529503.
- Regier, P.,Son, K.., Chen, X., Fang, Y., Jiang, P., Taylor, M., Wollheim, W.M. and Stegen, J., 2025. Allometric scaling of hyporheic respiration across basins in the Pacific Northwest United States. Journal of Geophysical Research: Biogeosciences, 130(3), p.e2024JG008344.
- Rathore S.S., D. Svyatskiy, E. Coon, Son, K.., and S.L. Painter. 2024. “Modeling the Effects of Artificial Drainage on Agriculture-dominated Watersheds using a Fully Distributed Integrated Hydrology Model.” Water Resources Research 60, no. 6:Art. No. e2023WR035993.
- Danczak, R.E., Garayburu-Caruso, V.A., Renteria, L., McKever, S.A., Otenburg, O.C., Grieger, S.R., Son, K., Kaufman, M.H., Fulton, S.G., Roebuck, J.A. and Myers-Pigg, A.N., 2023. Riverine organic matter functional diversity increases with catchment size. Frontiers in Water, 5, p.1087108.
- Son, K., Fang, Y., Gomez‐Velez, J.D., Byun, K. and Chen, X., 2022. Combined Effects of Stream Hydrology and Land Use on Basin‐Scale Hyporheic Zone Denitrification in the Columbia River Basin. Water Resources Research, 58(12), p.e2021WR031131.
- Mudunuru, M.K., Son, K., Jiang, P., Hammond, G. and Chen, X., 2022. Scalable deep learning for watershed model calibration. Frontiers in Earth Science, 10, p.1026479.
- Son, K., Fang, Y., Gomez‐Velez, J.D. and Chen, X., 2022. Spatial microbial respiration variations in the hyporheic zones within the Columbia River Basin. Journal of Geophysical Research: Biogeosciences, 127(11), p.e2021JG006654.
- Jiang, P., Son, K., Mudunuru, M.K. and Chen, X., 2022. Using mutual information for global sensitivity analysis on watershed modeling. Water Resources Research, 58(10), p.e2022WR032932.
- Hung, F., Son, K. and Yang, Y.E., 2022. Investigating uncertainties in human adaptation and their impacts on water scarcity in the Colorado river Basin, United States. Journal of Hydrology, 612, p.128015.
- Chen, X., Lee, R.M., Dwivedi, D., Son, K., Fang, Y., Zhang, X., Graham, E., Stegen, J., Fisher, J.B., Moulton, D. and Scheibe, T.D., 2021. Integrating field observations and process-based modeling to predict watershed water quality under environmental perturbations. Journal ofHydrology, 602, p.125762.
- Yang, Y.E., Son, K., Hung, F. and Tidwell, V., 2020. Impact of climate change on adaptive management decisions in the face of water scarcity. Journal of Hydrology, p.125015
- Contosta, A.R., Casson, N.J., Garlick, S., Nelson, S.J., Ayres, M.P., Burakowski, E.A., Campbell, J., Creed, I., Eimers, C., Evans, C. and Fernandez, I., 2019. Northern forest winters have lost cold, snowy conditions that are important for ecosystems and human communities. Ecological Applications, 29(7), p.e01974
- Son, K., Lin, L., Band, L. and Owens, E.M., 2019. Modelling the interaction of climate, forest ecosystem, and hydrology to estimate catchment dissolved organic carbon export. Hydrological Processes, 33(10), pp.1448-1464.
- Son, K. and Tague, C., 2019. A top–down soil moisture and sap flux sampling design of a rain–snow transition mountain watershed. Hydrological Processes, 33(11), pp.1553-1568.
- Son, K. and Tague, C. Effect of climate warming on ecohydrologic fluxes of two Sierra Nevada watersheds, Ecohydrology ; 10.1002/eco.2053
- Son, K., Tague. C and Hunsaker, C.T Effects of Model Spatial Resolution on Ecohydrologic Predictions and Their Sensitivity to Inter-Annual Climate Variability, Water 2016, 8, 321; doi:10.3390/w8080321
- Kim, J., Noh, J., Son, K. and Kim, I., 2012. Impacts of GIS data quality on determination of runoff and suspended sediments in the Imha watershed in Korea. Geosciences Journal, 16(2), pp.181-192.
- J. Kim, K. Son, J. Noh and S. Lee. Estimation of Suspended Sediment Load in Imha- Andong Watershed using SWAT Model, J. of KSEE / Vol. 30, No. 12, 2008.
- Son, K., and Kim, J., Application of Proxy-basin Differential Split-Sampling and Blind- Validation Tests for Evaluating Hydrological Impact of Climate change Using SWAT, Journal of KWRA, Vol. 41, No. 10, 969-982, 2008. 10.
- K. Son and M. Sivapalan. Improving model structure and reducing parameter uncertainty in conceptual water balance models through the use of auxiliary data, Water Resources Research, VOL. 43, W01415, doi: 10.1029/2006WR005032, 2007.
- Kim, J.K., Son, K.H., Noh, J.W., Jang, C.L. and Ko, I.H., 2006. Multi-variable and Multi-site Calibration and Validation of SWAT for the Gap River Catchment. Journal of Korea Water Resources Association, 39(10), pp.867-880.
- Kim, J.K., Son, K.H., Noh, J.W., Jang, C.L. and Ko, I.H., 2006. Evaluation of urbanization effect and analysis of hydrological characteristics in the Gap River catchment using SWAT. Journal of Korea Water Resources Association, 39(10), pp.881-890.