Sponsor
Portland State University. Department of Civil & Environmental Engineering
First Advisor
Scott Wells
Date of Publication
1-1-2011
Document Type
Thesis
Degree Name
Master of Science (M.S.) in Civil & Environmental Engineering
Department
Civil and Environmental Engineering
Language
English
Subjects
Dynamical Downscaling, Extreme Precipitation, NARCCAP, Climatic changes -- Environmental aspects -- Oregon -- Willamette River Watershed, Precipitation variability -- Oregon -- Willamette River Watershed, Weather -- Environmental aspects -- Oregon -- Willamette River Watershed, Willamette River Watershed (Or.) -- Climate -- Mathematical models
DOI
10.15760/etd.327
Physical Description
1 online resource (v, 50 p.) : col. ill., col. maps
Abstract
One important aspect related to the management of water resources under future climate variation is the occurrence of extreme precipitation events. In order to prepare for extreme events, namely floods and droughts, it is important to understand how future climate variability will influence the occurrence of such events. Recent advancements in regional climate modeling efforts provide additional resources for investigating the occurrence of extreme events at scales that are appropriate for regional hydrologic modeling. This study utilizes data from three Regional Climate Models (RCMs), each driven by the same General Circulation Model (GCM) as well as a reanalysis dataset, all of which was made available by the North American Regional Climate Change Assessment Program (NARCCAP). A comparison between observed historical precipitation events and NARCCAP modeled historical conditions over Oregon's Willamette River basin was performed. This comparison is required in order to investigate the reliability of regional climate modeling efforts. Datasets representing future climate signal scenarios, also provided by NARCCAP, were then compared to historical data to provide an estimate of the variability in extreme event occurrence and severity within the basin. Analysis determining magnitudes of two, five, ten and twenty-five year return level estimates, as well as parameters corresponding to a representative Generalized Extreme Value (GEV) distribution, were determined. The results demonstrate the importance of the applied initial/boundary driving conditions, the need for multi-model ensemble analysis due to RCM variability, and the need for further downscaling and bias correction methods to RCM datasets when investigating watershed scale phenomena.
Rights
In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/ This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).
Persistent Identifier
http://archives.pdx.edu/ds/psu/7084
Recommended Citation
Halmstad, Andrew Jason, "Investigating Future Variation of Extreme Precipitation Events over the Willamette River Basin Using Dynamically Downscaled Climate Scenarios" (2011). Dissertations and Theses. Paper 327.
https://doi.org/10.15760/etd.327
Comments
Portland State University. Dept. of Civil & Environmental Engineering