Water Temperature Controls for Regulated Canyon‐Bound Rivers

A study on the Colorado River within Grand Canyon National Park reveals that water temperature dynamics are primarily controlled by shortwave radiation and hydropeaking flow conditions, with significant variability due to topographic shading. The research adapted a dynamic river routing and temperature model to simulate temperatures over 18 years, achieving high accuracy (RMSE of 0.93°C). Findings indicate that reservoir release temperatures dominate upstream thermal regimes, while downstream influences shift toward discharge, shortwave radiation, and air temperature. This underscores the critical role of spatial and temporal shading patterns in predicting water temperatures in canyon-bound rivers.

Mihalevich, B. A., Neilson, B. T., Buahin, C. A., Yackulic, C. B., & Schmidt, J. C. (2020). Water Temperature Controls for Regulated Canyon‐Bound Rivers. Water Resources Research, 56(12). Portico. https://doi.org/10.1029/2020wr027566