Abstract
The impact of climate change on river discharge in Japanese basins is analyzed by feeding future climate projection data into a distributed rainfall-runoff model. The projection data used consists of daily surface and subsurface runoff data downscaled by hourly precipitation for the current climate experiment (1979-2003), the near future climate experiment (2015-2039), and the future climate experiment (2075-2099), which were simulated by a high resolution general circulation model (MRI-AM20km) developed by the Meteorological Research Institute, Japan Meteorological Agency. The main findings of runoff simulations are as follows: 1) clear changes of hourly flood peak discharge, daily drought discharge and monthly discharge were detected; 2) for each discharge, the degree of the changes differs according to location; and 3) the changes appear in the near future climate experiment, which become clear in the future climate experiment.
