Record Details
Simulating extreme total water levels using a time-dependent, extreme value approach
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Simulating extreme total water levels using a time-dependent, extreme value approach |
| Names |
Serafin, Katherine A.
(creator) Ruggiero, Peter (advisor) |
| Date Issued | 2013-10-16 (iso8601) |
| Note | Graduation date: 2014 |
| Abstract | Coastal flood hazard zones and the design of coastal defenses are often devised using either the maximum recorded total water level (TWL) or a 'design' event such as the 100-year return-level flood, usually projected from observed extreme events. Despite technological advances driving more consistent instrumental records of wave heights and water levels, the observational record may be short, punctuated with intermittent gaps, and vary in quality. These issues in the observational record result in limited estimates of extreme return-level events. We present a model that simulates the various components (waves, non-tidal residuals, and tides) of TWLs on sandy beaches in a Monte Carlo sense, taking into account the conditional dependencies that exist between the components. Extreme events are modeled using non-stationary extreme value distributions that include the effects of seasonality and climate variability. The resulting synthetic TWL time series allow for empirical extraction of return level events and the ability to robustly estimate and assess present-day flood and erosion hazards. We demonstrate this approach along a northern Oregon, USA littoral cell and evaluate both the chronic and extreme coastal hazards affecting the area. Simulations result in extreme TWL return levels up to 90cm higher than those estimated from the "observational" TWL record which results in approximately 25% more coastal flooding during the simulated 100-year return level event as compared to that event computed using "observational" data only. More robust estimates of extreme TWLs and tighter confidence bounds on return level events can aid coastal engineers, managers, and emergency planners in evaluating exposure to hazards. |
| Genre | Thesis/Dissertation |
| Access Condition | http://creativecommons.org/licenses/by-nc-nd/3.0/us/ |
| Topic | total water level |
| Identifier | http://hdl.handle.net/1957/44427 |
