TRAMS (the Tropical Region Atmospheric Modeling for South China Sea) is based on Grapes non-hydrostatic meso-scale model. In the model the semi-Lagrangian semi-implicit time difference scheme is adopted, Helmholtz formula is used to obtain the implicit solution. The physical process mainly includes: long-wave/ short-wave radiation, cloud microphysics, turbulence, deep/shallow convection and land surfaces parameterization schemes.
Dynamical core: including 3D hydrostatic reference atmosphere, nonlinear terms multi-stage calculation, physical process tendency implicit solution and dynamic process coupling, to form a new calculation scheme for the dynamic process.
Physical process: Among all of those schemes, updating work focus on the R&D of sea and land surface parameterization scheme (SMS scheme), the improvement of cumulus parameterization scheme (NSAS scheme) and the introduction of the scheme of parameterization of gravity wave drag (KA95 scheme).
Operational running: TRAMS runs four times per day (00/06/12/18UTC), issues the 168 hours weather forecasts at 00z and 12z. The area of the forecasts covers 81.6oE-160.8oE,0.8oN-50.5oN, while the horizontal resolution is 0.36o with 55 vertical levels.
Operational performance: the average errors for 24/48/72 h typhoon track forecast in the year 2015 are about 73.8/118.6/178.5km.