A Critical Evaluation of the Application of Natural Hazard and Climate Models.
Boehlert, Brent.
2015
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Abstract: Planning for
natural hazards and climate change requires that we develop the best possible
understanding of future hydroclimatic conditions. Modeling tools have become essential
in meeting this goal, but selecting the most appropriate models and distilling
actionable findings from their outputs is still a major challenge. In this research, we
investigate this issue from two perspectives: ... read more(1) the evaluation of hypothesized natural
hazard models, with a focus on predicting flooding events (Chapters 1 and 2); and (2)
patterns of agreement and uncertainty in water availability projections derived from a
wide array of climate model ensembles (Chapter 3). The first chapter evaluates the
appropriateness of traditional metrics of `goodness-of-fit' as measures of the
performance of a hypothesized natural hazard model (i.e., the applicability of a
selected probability density function). We find that goodness-of-fit can be quite
misleading, causing us to reject the correct model and generate potentially large errors
in design event (e.g., 1000-year flood) estimation in the process. We propose an
alternative metric that gives a more balanced assessment of goodness-of-fit. In the
second chapter, we introduce a property called transformational concordance. This
property can be used to evaluate whether a hypothesized model and its distributional
behavior are consistent with observations. Through our analysis of concordance, we
reveal systematic bias in GEV parameter estimation, which is cause for significant
concern given the wide application of the model for flood and other natural hazard
modeling. The third chapter focuses on improving our understanding of the timing,
location, and magnitude of climate change impacts on water needs and availability. Using
a wide range of recently available climate model ensembles, we explore the spatial and
temporal patterns of inter-model agreement and uncertainty in projected river runoff,
irrigation water requirements, and basin storage yield. Cost estimates of adapting
global water supply systems are developed for each ensemble, and implications for water
management are discussed.
Thesis (Ph.D.)--Tufts University, 2015.
Submitted to the Dept. of Civil Engineering.
Advisor: Richard Vogel.
Committee: Kenneth Strzepek, Susan Solomon, Laurie Baise, and Nicholas Matalas.
Keywords: Hydrologic sciences, and Climate change.read less - ID:
- 2514nx56s
- Component ID:
- tufts:21370
- To Cite:
- TARC Citation Guide EndNote
