Quantifying the impact of small scale unmeasured rainfall variability on urban runoff through multifractal downscaling: A case study

JOURNAL OF HYDROLOGY

卷:442

Article

Gires, A.¹  Onof, C.²  Maksimovic, C.²  Schertzer, D.¹  Tchiguirinskaia, I.¹  Simoes, N.^2,3 

[1] Univ Paris Est, Ecole Ponts ParisTech, LEESU, F-77455 Cite Descartes, Marne La Vallee, France

[2] Univ London Imperial Coll Sci Technol & Med, Dept Civil & Environm Engn, London, England

[3] Univ Coimbra, Dept Civil Engn, Coimbra, Portugal

关键词: Rainfall variability;    Downscaling;    Multifractals;    Ensemble predictions;    Urban runoff;   

DOI  :  10.1016/j.jhydrol.2012.04.005

来源: Elsevier

【 摘 要 】

This paper aims at quantifying the uncertainty on urban runoff associated with the unmeasured small scale rainfall variability, i.e. at a resolution finer than 1 km x 1 km x 5 min which is usually available with C-band radar networks. A case study is done on the 900 ha urban catchment of Cranbrook (London). A frontal and a convective rainfall event are analysed. An ensemble prediction approach is implemented, that is to say an ensemble of realistic downscaled rainfall fields is generated with the help of universal multifractals, and the corresponding ensemble of hydrographs is simulated. It appears that the uncertainty on the simulated peak flow is significant, reaching for some conduits 25% and 40% respectively for the frontal and the convective events. The flow corresponding the 90% quantile, the one simulated with radar distributed rainfall, and the spatial resolution are power law related. (C) 2012 Elsevier B.V. All rights reserved.

【 授权许可】

Free