Abstract
Possible impacts of climate change on human life and economic activity are being pointed out, and it is important for urban areas with dense population to implement countermeasures. This study aims to analyze changes in risks of annual high temperature / precipitation days up to 2050 for approximately 3600 urban areas in the world under different climate change scenarios. It also analyzes major factors behind such changes for addressing the planning measures. As a result, we found that the risks of annual high temperature days will increase in all the urban areas caused by an increase in the number of high temperature days, and the increase in number will be all the more conspicuous as climate change level becomes high. The risks of annual high precipitation days will also increase in many urban areas, while they will decrease in a quarter of urban areas in the world. Furthermore, the major causes for the increase in the high precipitation risks will be different among the urban areas. Planning measures will be required for urban areas by taking into account the factor expected to dominantly contribute to the risk changes.