Author(s): S. Y. Liong; S. C. Liew; M. T. Vu; V. S. Raghavan; V. T. Phan
Linked Author(s):
Keywords: Dynamical downscaling; Regional Climate Model; Proxy data; Reanalyses; Intensity-Duration-Frequency; Transboundary
Abstract: This paper focuses on finding proxies data for rainfall data in the data sparse Southeast (SE) Asia region. Lack of good quality and/or long record rainfall data are often the case in SE Asia. This situation leads to challenges in, for examples, deriving reliable storm drainage design curves, assessing flow rate in transboundary catchment, anticipating flow rate for hydropower station, optimally managing crop growths, etc. Two of the aforementioned issues are discussed in this paper: storm drainage design curves (IntensityDuration-Frequency curves), and transboundary catchment model. The proposed proxy data come from dynamically downscaled reanalyses data for the domain of interest. In this study, a Regional Climate Model (RCM), Weather Research and Forecasting (WRF), is used for the entire SE Asia. The proxy data for the current climate are derived from WRF, driven by the reanalyses data, for the SE Asia domain at a high spatial resolution of 30×30 km. For data sparse sites it is absolutely crucial to apply regional frequency analysis by using downscaled reanalyses data as proxy to derive higher confidence level IDF curves with longer records. The proposed approach has been successfully demonstrated and implemented on Singapore, Jakarta and Vietnam regions. Another issue considered is the trans-boundary problem where data sharing between two countries is often a challenge. This paper shows a transboundary catchment, Da River catchment, where upstream is in the Chinese territory while downstream is in the Vietnam territory. A SWAT model is applied; upstream region’s rainfall data are derived from the WRF model to rainfall stations in China. Again, the study shows that precipitation data originated from downscaled reanalysis data are very useful proxies, as station data, in transboundary catchment.
Year: 2014