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Title: Contrasting rainfall-runoff characteristics of floods in desert and Mediterranean basins
Abstract. Catchment-scale hydrological studies on drylands are lacking because of thescarcity of consistent data: observations are often available at the plotscale, but their relevance for the catchment scale remains unclear. Adatabase of 24 years of stream gauge discharge and homogeneoushigh-resolution radar data over the eastern Mediterranean allows us to describe the properties of floods over catchments spanning from desert toMediterranean climates, and we note that the data set is mostly of moderateintensity floods. Comparing two climatic regions, desert and Mediterranean,we can better identify specific rainfall-runoff properties. Despite the large differences in rainfall forcing between the two regions, the resulting unitpeak discharges and runoff coefficients are comparable. Rain depth andantecedent conditions are the most important properties to shape floodresponse in Mediterranean areas. In deserts, instead, storm core propertiesdisplay a strong correlation with unit peak discharge and, to a lesser extent,with runoff coefficient. In this region, an inverse correlation with meancatchment annual precipitation suggests also a strong influence of localsurface properties. Preliminary analyses suggest that floods in catchmentswith wet headwater and dry lower section are more similar to desertcatchments, with a strong influence of storm core properties on runoffgeneration.  more » « less
Award ID(s):
1632048
PAR ID:
10113327
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Hydrology and Earth System Sciences
Volume:
23
Issue:
6
ISSN:
1607-7938
Page Range / eLocation ID:
2665 to 2678
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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