Research Mentor(s)
Mitchell, Robert
Description
The River Basin Model (RBM) is used to assess how stream temperatures will change in the Nooksack River due to warming climates by tracking heat exchanges along stream segments. Before modeling forecasted climate scenarios, I first calibrated the model to observed historical stream temperatures. The calibration of the RBM to a stream network involves the adjustment of eleven different variables until the simulated temperatures match observed historical stream temperatures. Because the manual process of calibrating the model is extremely time consuming, I developed a Python script to converge on the optimal variables required for the RBM calibration. The script adjusts variables until it determines a statistically acceptable fit between the simulated and observed stream temperatures, until it detects that the continued variance of a variable causes a decrease in the statistics, or until the variable hits the imposed bounding limits. I used my optimization script to calibrate the RBM in each of the three sub-basins in the Nooksack River basin: the South Fork, Middle Fork, and the North Fork. I used outputs from hydrology models produced by Murphy (2016) as inputs to the RBM and calibrated the model to observed temperatures from USGS gauges in each of the sub-basins. My future objectives are to use the calibrated models in all three basins with forecasted climate data to simulate the hydrology and stream-temperature response in the three forks of the Nooksack River into the 21st century.
Document Type
Event
Start Date
18-5-2020 12:00 AM
End Date
22-5-2020 12:00 AM
Department
Geology
Genre/Form
student projects, posters
Subjects – Topical (LCSH)
Climatology--Statistical; Hydrological forecasting--Washington (State)--Nooksack River Watershed; Climatic changes--Washington (State)--Nooksack River Watershed
Geographic Coverage
Nooksack River Watershed (Wash.)
Type
Image
Keywords
Calibration, Optimization, Nooksack River, Stream Temperature, Python, Script, Hydrology, RBM, River Basin Model, DHSVM, Distributed Hydrology Soil and Vegetation Model
Rights
Copying of this document in whole or in part is allowable only for scholarly purposes. It is understood, however, that any copying or publication of this document for commercial purposes, or for financial gain, shall not be allowed without the author’s written permission.
Language
English
Format
application/pdf
Included in
Calibration optimization of a stream temperature model applied to the Nooksack River
The River Basin Model (RBM) is used to assess how stream temperatures will change in the Nooksack River due to warming climates by tracking heat exchanges along stream segments. Before modeling forecasted climate scenarios, I first calibrated the model to observed historical stream temperatures. The calibration of the RBM to a stream network involves the adjustment of eleven different variables until the simulated temperatures match observed historical stream temperatures. Because the manual process of calibrating the model is extremely time consuming, I developed a Python script to converge on the optimal variables required for the RBM calibration. The script adjusts variables until it determines a statistically acceptable fit between the simulated and observed stream temperatures, until it detects that the continued variance of a variable causes a decrease in the statistics, or until the variable hits the imposed bounding limits. I used my optimization script to calibrate the RBM in each of the three sub-basins in the Nooksack River basin: the South Fork, Middle Fork, and the North Fork. I used outputs from hydrology models produced by Murphy (2016) as inputs to the RBM and calibrated the model to observed temperatures from USGS gauges in each of the sub-basins. My future objectives are to use the calibrated models in all three basins with forecasted climate data to simulate the hydrology and stream-temperature response in the three forks of the Nooksack River into the 21st century.