Prediction of extreme floods based on CMIP5 climate models: a case study in the Beijiang River basin, South China

Hydrology and Earth System Sciences. 2015;19(3):1385-1399 DOI 10.5194/hess-19-1385-2015

 

Journal Homepage

Journal Title: Hydrology and Earth System Sciences

ISSN: 1027-5606 (Print); 1607-7938 (Online)

Publisher: Copernicus Publications

Society/Institution: European Geosciences Union (EGU)

LCC Subject Category: Technology: Environmental technology. Sanitary engineering | Geography. Anthropology. Recreation: Environmental sciences

Country of publisher: Germany

Language of fulltext: English

Full-text formats available: PDF, XML

 

AUTHORS

C. H. Wu (School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510640, China)
G. R. Huang (School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510640, China)
H. J. Yu (School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510640, China)

EDITORIAL INFORMATION

Peer review

Editorial Board

Instructions for authors

Time From Submission to Publication: 40 weeks

 

Abstract | Full Text

The occurrence of climate warming is unequivocal, and is expected to be experienced through increases in the magnitude and frequency of extreme events, including flooding. This paper presents an analysis of the implications of climate change on the future flood hazard in the Beijiang River basin in South China, using a variable infiltration capacity (VIC) model. Uncertainty is considered by employing five global climate models (GCMs), three emission scenarios (representative concentration pathway (RCP) 2.6, RCP4.5, and RCP8.5), 10 downscaling simulations for each emission scenario, and two stages of future periods (2020–2050, 2050–2080). Credibility of the projected changes in floods is described using an uncertainty expression approach, as recommended by the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC). The results suggest that the VIC model shows a good performance in simulating extreme floods, with a daily runoff Nash–Sutcliffe efficiency coefficient (NSE) of 0.91. The GCMs and emission scenarios are a large source of uncertainty in predictions of future floods over the study region, although the overall uncertainty range for changes in historical extreme precipitation and flood magnitudes are well represented by the five GCMs. During the periods 2020–2050 and 2050–2080, annual maximum 1-day discharges (AMX1d) and annual maximum 7-day flood volumes (AMX7fv) are expected to show very similar trends, with the largest possibility of increasing trends occurring under the RCP2.6 scenario, and the smallest possibility of increasing trends under the RCP4.5 scenario. The projected ranges of AMX1d and AMX7fv show relatively large variability under different future scenarios in the five GCMs, but most project an increase during the two future periods (relative to the baseline period 1970–2000).