Downscaling Spatial Rainfall Field from Global Scale to Local Scale Using Improved Multiplicative Random Cascade Method
نویسندگان
چکیده
Synopsis Non-homogenous multiplicative random cascade method downscales spatial rainfall field from a coarse scale into a finer one. Currently, this kind of downscaling is less reliable even though it correctly produces a long term average spatial pattern. It fails reproducing the patterns in repeated trials; and there is a higher chance of magnitude fluctuation. These drawbacks are needed to overcome. In this study, a new method, named as random cascade Hierarchical and Statistical Adjustment (HSA) method, is introduced and tested to downscale 1.25 degree GAME Re-analysis data into 10-minute spatial resolution. The obtained results are highly improved, quite robust and reliable than the previous method.
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