The implicit nonlinear normal mode initialization (INMI) is applied to a tropical limited area shallow water model in spherical coordinates.The boundary condition for the INMI scheme is based on the boundary formulati...The implicit nonlinear normal mode initialization (INMI) is applied to a tropical limited area shallow water model in spherical coordinates.The boundary condition for the INMI scheme is based on the boundary formulation of the model.The INMI scheme is found to be very efficient in suppressing spurious gravity wave oscillation and providing a well balanced initial data set for the model.The INMI scheme involves solving a number of elliptic type equations with varying complexity.and hence an efficient numerical technique is required for solving such equations.In order to make INMI computationally more attractive,we are employing the multigrid method for solving all the elliptic type equations in the INMI scheme.The numerical procedures for the development of such multigrid solvers are briefly described.展开更多
Vertical profiles of virtual potential temperature,specific humidity,temperature at saturation points,moist static energies along with parcel condensing levels using minisonde data are analysed for two stations throug...Vertical profiles of virtual potential temperature,specific humidity,temperature at saturation points,moist static energies along with parcel condensing levels using minisonde data are analysed for two stations through which a mon- soon depression passed.The height of the cloud base came down as low as 910 hPa level from 835 hPa.Equivalent po- tential temperature increased in the vertical profile as well as in the conserved variable diagram as the depression ap- proached the station.Parcel condensing levels showed clearly inversion top and cloud top but not in all cases.Moist stat- ic energy showed an increase upto 10 kJ/kg as the depression approached.展开更多
文摘The implicit nonlinear normal mode initialization (INMI) is applied to a tropical limited area shallow water model in spherical coordinates.The boundary condition for the INMI scheme is based on the boundary formulation of the model.The INMI scheme is found to be very efficient in suppressing spurious gravity wave oscillation and providing a well balanced initial data set for the model.The INMI scheme involves solving a number of elliptic type equations with varying complexity.and hence an efficient numerical technique is required for solving such equations.In order to make INMI computationally more attractive,we are employing the multigrid method for solving all the elliptic type equations in the INMI scheme.The numerical procedures for the development of such multigrid solvers are briefly described.
文摘Vertical profiles of virtual potential temperature,specific humidity,temperature at saturation points,moist static energies along with parcel condensing levels using minisonde data are analysed for two stations through which a mon- soon depression passed.The height of the cloud base came down as low as 910 hPa level from 835 hPa.Equivalent po- tential temperature increased in the vertical profile as well as in the conserved variable diagram as the depression ap- proached the station.Parcel condensing levels showed clearly inversion top and cloud top but not in all cases.Moist stat- ic energy showed an increase upto 10 kJ/kg as the depression approached.
