Analysis on Spatial Variability of Rainfall in a Small Area Kim, Jong Pil; Kim, Won; Kim, Dong-Gu; Lee, Chanjoo;
This study deployed six rain gauges in a small area for a dense network observing rainfall and analyzed the spatial variability of rainfall. They were arranged in a rectangular grid with equal space of 60 m. The rainfall measurements from five gauges were analyzed during the period of 50 days because one was seriously affected by alien substance. The maximum difference in cumulative rainfall from them is approximately 38.5 mm. The correlation coefficients from hourly rainfall time series differ from each other while daily rainfall coincide. The coefficient of variation in hourly rainfall varies up to 224% and that in daily rainfall up to 91%. The results from uncertainty analysis show that with only four rain gauges areal mean rainfall cannot be estimated over 95% accuracy. For reliable flood prediction and effective water management it is required to develop a new technique for the estimation of areal rainfall.
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