Most severe disasters have included extreme rainfall intensity. Consequently, it is necessary to develop rainfall observation technology that provides observations over a large area over a short-term, with high accuracy. This study was conducted to clarify the accuracy of X-band multi-parameter radar (X-MP) over the Hokuriku region using rain-gauge data collected by the Japan Meteorological Agency (JMA) and the Water and Disaster Management Bureau under the Ministry of Land, Infrastructure, Transport and Tourism (MLIT). Additionally, this study analyzed results in terms of installed altitudes of rain-gauge stations and distance from the radar site to the rain-gauge station.
 Results of statistical analyses show that the distance from the radar site engenders lower accuracy of the X-MP.However the X-MP data accuracy was equal to that of rain-gauge data within a 20 km radius from the radar site. Although the X-MPs provide observations with high accuracy for rainfall observation, snowfall observation was less accurate. Therefore,quantitative snowfall estimation might improve the observation accuracy of the X-MP. Examination of the Z-R relation and the K_DP-R relation shows that Z-R might provide better accuracy than K_DP-R beyond a 30 km radius from the radar site. Results suggest the necessity of using and analyzing more observation data.

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 The United States, as a superpower, has begun to approach the Mekong River Basin, an international waterway.The Obama administration brought with it a shift in U.S. foreign policy, particularly addressing the ''rebalancing of Asia.'' However, this policy has been undertaken to restrain China, which exerts a strong influence on Southeast Asia. Moreover, the U.S. approach to the Mekong River was spurred by a shift to democracy in Myanmar. China has built successive dams on the river, reflecting a one-sided policy of exploitation that is increasingly straining the Mekong River Basin's water resources. Consequently, downstream countries have voiced criticism of Chinese projects and policies. International politics still entails ''power politics.'' Even if an issue involves the use of an international river, it is much more important to analyze trends of superpower policies and actions than to analyze an international cooperation framework.

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