Which vertical coordinate system is used in WRF mode?

The vertical direction uses terrain following mass coordinates

wrf refers to TheWeatherResearchandForecastingModel, a weather forecast model, which is known as the next generation mesoscale weather forecast model.

wrf mode is fully compressible and non-static mode, written in F90 language. ArakawaC grid points are used in the horizontal direction, and terrain following mass coordinates are used in the vertical direction. The wrf mode uses the third-order or fourth-order Runge-Kutta algorithm in time integration.