Coupling Poisson rectangular pulse and multiplicative microcanonical random cascade models to generate sub-daily precipitation timeseries

Abstract

To simulate the impacts of within-storm rainfall variabilities on fast hydrological processes, long precipitation time series with high temporal resolution are required. Due to limited availability of observed data such time series are typically obtained from stochastic models. However, most existing rainfall models are limited in their ability to conserve rainfall event statistics which are relevant for hydrological processes. Poisson rectangular pulse models are widely applied to generate long time series of alternating precipitation events durations and mean intensities as well as interstorm period durations. Multiplicative microcanonical random cascade (MRC) models are used to disaggregate precipitation time series from coarse to fine temporal

Rainfall intensity bursts and the erosion of soils: an analysis highlighting the need for high temporal resolution rainfall data for research under current and future climates

“…A common approach to the analysis of extreme rainfall intensities is the use of downscaling from daily maxima to sub-daily values, though this is normally only extended to the prediction of hourly maxima. Sub-hourly rainfall data are generated in some micro-canonical cascade downscaling models (Jebari et al, 2012;Kianfar et al, 2016;Paschalis et al, 2014;Pohle et al, 2018) though with only moderate success in generating realistic intensities. Müller and Haberlandt (2018) for instance employed a micro-canonical cascade model and report overestimation of 5 min intensities of up to 63 %, though their "model B2" resulted in overestimates averaging only 11 %.…”

“…These may involve average intensities tallied using data pooled from many rain days and which conceal variation among days. For instance, Polemio and Lonigro (2015) used a "monthly rainfall intensity", which is the monthly rainfall depth scaled by the number of rain days in that month. Others use a similar "daily rain intensity" (e.g.…”

A hybrid stochastic rainfall model that reproduces some important rainfall characteristics at hourly to yearly timescales

“…monthly, yearly) timescales. Small-scale rainfall temporal variability influ-ences short-term watershed responses such as flash floods (Reed et al, 2007) and subsequent transport of sediments (Ogston et al, 2000) and contaminants (Zonta et al, 2005). Large-scale rainfall temporal variability Tyralis et al, 2018) influences long-term resilience of human-flood systems (Yu et al, 2017), human health (Patz et al, 2005), food production (Shisanya et al, 2011), and the evolution of human society (Warner and Afifi, 2014) and ecosystems (Borgogno et al, 2007;Fernandez-Illescas and Rodriguez-Iturbe, 2004).…”

Does the complexity in temporal precipitation disaggregation matter for a lumped hydrological model?

“…Possible solutions are either (i) the generation of precipitation time series, e.g. by Poisson-cluster models (Onof et al 2000, and references therein), alternating renewal models (Haberlandt et al 2008, Callau Poduje and Haberlandt 2017, and combinations of rainfall generation models (Paschalis et al 2014, Pohle et al 2018, or (ii) the temporal disaggregation of observed precipitation time series of a coarser resolution, which are usually available for longer periods and higher network densities than high-resolution time series. Disaggregation has the advantage that it relies on real (measured) precipitation amounts and a correct representation of time series characteristics, e.g.…”