Open AccessEvaluation of flash flood severity in K orea using the modified flash flood index ( MFFI )
Author(s) -
Kim BS.,
Kim HS.
Publication year - 2014
Publication title -
journal of flood risk management
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.049
H-Index - 36
ISSN - 1753-318X
DOI - 10.1111/jfr3.12057
Subject(s) - flash flood , flood myth , environmental science , hydrology (agriculture) , surface runoff , flash (photography) , magnitude (astronomy) , intensity (physics) , geology , geography , ecology , physics , biology , geotechnical engineering , archaeology , quantum mechanics , astronomy , optics
This paper was initially motivated by a flash flood index ( FFI ) study performed by B haskar et al . and others that explained flash floods using a runoff perspective by extracting a rising curve gradient, the flood magnitude ratio, and flood response time variables from runoff hydrograph. However, the runoff data are not sufficient to estimate a robust flood magnitude ratio in K orea. In addition, the existing model is not able to consider high rainfall intensity, which is an important flash flood characteristic in K orea. Flood magnitude ratio variables, thus, were replaced by rainfall intensity variables. Then, the results were compared with the existing FFI . The spatial distribution of the flood event in the H an R iver basin that occurred in J uly 2006 showed that a modified FFI , which reflects rainfall characteristics, outperformed in representing damaged (flash flood occurrence) areas in the past. Furthermore, the FFI for three different time windows (early, middle, and late periods) for the H an R iver basin during the localised intensive rainfall in J uly 2006 were analysed. Analysis of spatiotemporal distribution showed that sudden intensity was pronounced in the S eoul area during the first 10 days of J uly. During the second 10 days of J uly, a probable high‐intensity flash flood appeared in the G angwon‐do area. Meanwhile, an onsite survey of the G angwon‐do area showed that the actual occurrences of a high‐intensity flash flood were largely in agreement with the predictions made by the model.