Work

Precipitation variability within an urban monitoring network via microcanonical cascade generators

Year: 2015

Type: article

Abstract: . Understanding the variability of precipitation at small scales is fundamental in urban hydrology. Stochastic models of precipitation are required to feed hydrodynamic models with high resolution data, in order to obtain a probabilistic assessment of urban drainage networks. Microcanonical random cascades are considered here to represent precipitation time series collected in 25 gauges of a monitoring network in Warsaw, Poland. Breakdown coefficients (BDCs) are calculated separately for a hierarchy of subdaily timescales from 5 min (time resolution) to 1280 min, for all gauges. Strong deformations of BDC histograms in form of sharp peaks at small timescales are observed due to the truncation of precipitation depths recorded by gauges. Satisfactory smoothing of empirical BDC histograms is obtained statistically by a slight randomization of nonzero precipitation amounts. The scarce representation of BDCs at large timescales, due to the short period of observation, is solved by the introduction of an algorithm based on overlapping moving windows. BDC histograms are modeled by a 2N-B distribution, which combines two Normal (N) and one Beta (B) distribution. A clear evolution of the distribution from 2N-B at small timescales, to N-B at intermediate timescales, and finally to Beta distribution for large timescales is observed in all gauges. The performance of the microcanonical cascades is evaluated for the considered gauges. Synthetic time series are analyzed with respect to their intermittency and variability of intensity, and compared to observed series. BDC histograms, for each timescale, are compared among the 25 gauges in Warsaw, and with other gauges located in Poland and Germany. The cluster analysis is used to identify patterns of BDC histograms among analyzed set of gauges and timescales, as well as to detect outlier gauges.

Source: Hydrology and earth system sciences

DOI: 10.5194/hess-19-485-2015

Authors: P. Licznar, C. De Michele, W. Adamowski

Institutions: Wrocław University of Science and Technology, Politecnico di Milano, John Paul II Catholic University of Lublin

Language: English

Topic: Precipitation Measurement and Analysis

Subfield: Atmospheric Science

Field: Earth and Planetary Sciences

Domain: Physical Sciences

SDGs: Sustainable cities and communities, Clean water and sanitation

Open Access status: gold

Estimated APC paid: $1,725