Modeling Intensity-Duration-Frequency curves for the whole range of
precipitation: A comparison of models
Abstract
Intensity-Duration-Frequency curves are useful in water resources
engineering for the planning and design of hydrological structures. As
opposed to the common use of only extreme data to build IDF curves,
here, we use all the non-zero rainfall intensities, thereby making
efficient use of the available information. As a parametric model, we
use the Extended Generalized Pareto Distribution (EGPD) for the non-zero
intensities. We consider three commonly used approaches to build the IDF
curves. The first approach is based on the scale-invariance property of
rainfall, the second relies on the general IDF formulation of
Koutsoyiannis et al. (1998) while the last approach is purely
data-driven (Overeem et al., 2008). Using these three approaches, and
some extensions around them, we build a total of 10 models for the IDF
curves and then we compare them in a split-sampling cross-validation
framework. We consider a total of 81 stations at 10 min resolution in
Switzerland. The results reveal the model based on the data-driven
approach as the best model. It is able to correctly model the observed
intensities across duration while being reliable and robust. It is also
able to reproduce the space and time variability of extreme rainfall
across Switzerland.