A numerical study of mesoscale precipitating system along Meiyu Front observed during GAME-HUBEX 1998
K. Nakamura (1), Y. Fujiyoshi (2)
(1) Frontire Research Center for Global Change/Ocean Research Institute, University of Tokyo
(2) Frontire Research Center for Global Change/Institute of Low Temperature Science, Hokkaido University
In order to improve our understanding of the mesoscale organization p
rocesses, we performed a numerical experiment of the disturbance observed near F
uyuang radar site (115.83 E, 32.93 N) on July 2nd, 1998, during GAME/HUBEX 98.
The model used in this study is Non Hydrostatic Model (NHM) developed by MRI. We
performed two runs using two datasets, i.e., the GAME-Reanalysis and ECMWF data
set, for initial and boundary conditions, and we investigate the organizing pro
cess by comparing the results of two runs.
In both runs, the model successfully reproduced the development of the
large-scale horizontal shear, convergence, and the precipitation along
the Mei-yu front. However, the disturbance of the GAME-Reanalysis run
was too strong and moved too fast to the northeastward, and after its
movement there is no intense convection. On the other hand, in the ECMWF run, t
here occurred many convection systems along the front region and properly reprod
uced the persistent heavy rainfall area. We preformed several experiments (the
wetness parameter w=0.1 and w=1.0) to investigate the effect of the surface cond
itions. It is shown that although the effect of the wetness parameter on the bo
undary layer structure is large, its effect on the convective activity seems to
be small.
Submittal Information
Name :
Date :
Dr. Kozo Nakamura
27-Jul-04-14:40:17
Organization :
Theme :
Frontier Research Center for Global Change/Ocean Research Institute University of Tokyo