Continuous rainfall simulation: estimation at ungauged locations

Abstract

Continuous simulation of extended rainfall sequences is becoming an increasingly important tool in rainfall-runoff modelling and design flood estimation. Recently, a nonparametric approach has been developed in which continuous (sub-daily) rainfall fragments are conditioned to daily rainfall on the current day and the rainfall state (wet or dry) on adjacent days using a k-nearest neighbour conditional resampling algorithm, with this method performing well in simulating both Intensity-Frequency-Duration characteristics and antecedent moisture when tested in Sydney, Australia. A limitation of this approach, however, is that extended pluviograph records at the location of interest are required, limiting applicability to only a small number of locations across Australia where such records are available.