| In developing countries、it is urgent to implement non-structural flood countermeasures such as flood forecasting/warning systems to promote early evacuation in addition to structural measures. However、it is difficult to implement such systems in ungauged basins in developing countries due to lack of hydrological information because they require costly facilities and highly advanced observation、for example、with precipitation telemeters and radars. On the other hand、satellite-based global rainfall data are widely available for public use、and research has been in progress to apply this type of data to a broad range of areas including flood management in ungauged basins. In particular、a near-real-time rainfall product called GSMaP_NRT has drawn much attention because of its high spatial and temporal resolutions and short data latency. This product is considered very promising for flood forecasting and warning in ungauged basins in developing countries. However、research has found that satellite-based rainfall products in general tend to underestimate rainfall when compared with ground precipitation、hich poses a problem in their use for flood forecasting and warning. Thus、a correction method for satellite data is necessary to use them for flood runoff analysis. Shiraishi et al. developed a correction method in their 2009 study、and found that the method can drastically reduce the error rate under certain conditions. This paper will briefly review the development of the correction method by Shiraishi et al. and describe its applicability assessment over river basins in Japan. |
