半隐式半拉格朗日动力框架的动能谱分析(2)

other factors such as physical parameterization processes, the simulated kinetic energy spectrum in the smallmeso scale approaches closely the observed atmospheric kinetic energy spectrum, otherwise, the simulated kinetic energy spectrum in the small meso scale has larger errors, and correspondingly its kinetic energy spectrum in the large scale also has larger errors. In addition, the time step has significant impact on the spin up process, when a smaller time step is used, the model can develop well the reasonable kinetic energy spectral structure in the spectral space and can generate and develop reasonable smallmeso scale systems in the physical space during the spin up period, while a larger time step is used, the opposite is true. Finally, it is found that the kinetic energy spectra derived from GRAPES and WRF are

consistent each other, and the global medium range model GRAPES can simulate perfectly the characteristic of E∝k-3

for the large scale kinetic energy spectrum. In summary, this investigation on the simulated kinetic energy spectrum of the GRAPES model reveals several meaningful results, which provide a scientific guidance for further research, improvement and application of the GRAPES model, and also demonstrates the effectiveness of kinetic energy spectrum in evaluating numerical models.

Key words Kinetic energy spectrum, GRAPES model, Semi Lagrangian dynamic framework, Highest effective resolution scale, Maximum effective time step, Small meso scale, Spin up