A comparison of river discharge calculated by using a regional climate model output with different reanalysis datasets in 1980s and 1990s

Tuesday, 16 December 2014
Xieyao Ma1, Takao Yoshikane2, Masayuki Hara1, Sachiho A. Adachi3, Yasutaka Wakazuki1,4, Hiroyuki Kawase1,5 and Fujio Kimura1, (1)Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan, (2)Atmosphere and Ocean Research Institute, University of Tokyo, Tokyo, Japan, (3)RIKEN Advanced Institute for Computational Sciences, Kobe, Japan, (4)University of Tsukuba, Tsukuba, Japan, (5)Meteorological Research Institute, Ibaraki, Japan
To check the influence of boundary input data on a modeling result, we had a numerical investigation of river discharge by using runoff data derived by a regional climate model with a 4.5-km resolution as input data to a hydrological model. A hindcast experiment, which to reproduce the current climate was carried out for the two decades, 1980s and 1990s. We used the Advanced Research WRF (ARW) (ver. 3.2.1) with a two-way nesting technique and the WRF single-moment 6-class microphysics scheme. Noah-LSM is adopted to simulate the land surface process. The NCEP/NCAR and ERA-Interim 6-hourly reanalysis datasets were used as the lateral boundary condition for the runs, respectively. The output variables used for river discharge simulation from the WRF model were underground runoff and surface runoff. Four rivers (Mogami, Agano, Jinzu and Tone) were selected in this study. The results showed that the characteristic of river discharge in seasonal variation could be represented and there were overestimated compared with measured one.