Student Scholar Symposium Abstracts and Posters

Document Type


Publication Date

Fall 11-29-2022

Faculty Advisor(s)

Dr. Thomas Piechota


The Colorado River Basin is crucial to the Western United States, providing water for seven states and Mexico. Historical and future periods of drought and surplus are analyzed in 17 Colorado River stations. Unimpaired streamflow data are evaluated from the U.S. Geological Survey, Bureau of Reclamation, and Coupled Modeled Intercomparison Projection 5 from 1950-2099. Future projections are based on eight climate scenarios. Four climate models (HadGEM2-ES, CNRM-CM5, CanESM2, MI-ROC5) are observed at Representative Concentration Pathways (RCP) 4.5 and 8.5 emission scenarios. Furthermore, the ensemble water year means of the four models are analyzed. The durations of drought or surplus, magnitudes, intensities, and water year flows are compared for historical and future periods. Results demonstrate a notable difference between the historical record and future projections. Drought and surplus severity are projected to increase in both RCP 4.5 and 8.5 scenarios. The HadGEM2-ES and MI-ROC5 models predict drier settings, while the CNRM-CM5 and CanESM2 models project wetter scenarios. The critical Lees Ferry station, to which most upper basin stations flow, is expected to see drought and surplus duration and magnitude two times larger than the historical record. Due to climate change, the two streamflow extremes of drought and surplus continue to worsen. As the Western U.S., and other parts of the world, suffer from intense and uncertain weather conditions, it is crucial to evaluate drought and surplus patterns and advance flow modeling. In addition, proper water management and infrastructure are needed to adapt to the changing climate.


Presented at the Fall 2023 Student Scholar Symposium at Chapman University.

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