Table 2.

Main configuration options in BRAMS 5.2

Basic equations	Non-hydrostatic time-split compressible Option for complete, mass conservative formulation for the Exner function prognostic equation
Coordinates	Vertical coordinate: Standard Cartesian coordinate Terrain-following height coordinate Horizontal coordinate: Standard Cartesian coordinate Rotated polar-stereographic transformation
Computational grid	Arakawa-C grid staggering on horizontal, Lorenz grid on vertical Vertical grid-spacing can vary with height One-way nesting only
Time integration	Time differencing: Hybrid combination of leapfrog and forward-in-time, with option for Robert-Asselin-William time filter (William, 2009) Runge-Kutta 2nd and 3rd order (Wicker and Skamarock, 1998, 2002) Adams-Bashforth-Moulton 3rd order (Wicker, 2009) Time-split small step for acoustic and gravity-wave modes: Small step horizontally-explicit, vertically-implicit Divergence damping option
Advection schemes	Forward upstream of 2nd order (Tremback et al., 1987) Monotonic advection scheme for scalars (Walcek, 2000) 1st to 6th order advection options (horizontal and vertical, Wicker and Skamarock, 1998, 2002) with positivity constraint (Skamarock, 2006).
Turbulence closure	Smagorinsky (1963), Lilly (1962) and Hill (1974) closure formulation Deardorff (1980) level 2.5 scheme Mellor-Yamada level 2.5 scheme (Mellor and Yamada, 1982) Nakanishi & Nino (2004) TKE based formulation Taylor’s theory based formulation (Campos Velho, 1998)
Cloud microphysics	Single-moment bulk scheme (Walko et al., 1995) Double-moment bulk scheme (Meyers et al., 1997) Thompson double-moment and aerosol aware scheme (Thompson and Eidhammer, 2014)
Radiation	CARMA (Toon et al., 1989) schemes for long- and short-wave radiation RRTMG (Iacono et al., 2008) schemes for long- and short-wave radiation
Convective Parameterization	Modified Kuo for deep convection (Tremback, 1990) For shallow convection based on the heat engine approach (Souza, 1999) Grell and Deveny (2002) ensemble version for deep convection Grell and Freitas (2014) ensemble version, scale and aerosol aware for deep and shallow convection
Surface processes and lower boundary	LEAF-3 soil-vegetation-snow parameterization (Walko et al., 2000) Town Energy Budget (TEB) scheme for urban areas (Freitas et al., 2007) Joint UK Land Environment Simulator scheme (Moreira et al., 2013) Fire spreading model (Mandel et al., 2010, Menezes, 2015)*
Chemical processes	Gas/aqueous phase chemistry with CCATT (Longo et al., 2013) and SPM Freitas et al., 2005a) modules. Photochemistry with LUT, FAST-TUV and FAST-J photolysis calculation SPACK chemical mechanism pre-processor PREP-CHEM-SRC pre-processor emission fields (Freitas et al., 2011) Rosenbrock 2nd and 3rd order solvers Dry and wet deposition
Aerosol processes	Simple aerosol model for volcanic ash, biomass burning, sea salt and urban aerosols (Longo et al., 2013) MATRIX aerosol model (Bauer et al., 2008)* Aerosol direct effect included in CARMA radiation scheme
Upper boundary condition	Rigid lid Rigid lid with a high-viscosity layer aloft
Lateral boundary condition	Klemp and Wilhelmson (1978) radiative condition Large-scale nudging boundary conditions (Davies, 1983)
Initialization and Data Assimilation	Horizontally homogeneous from a single sounding RAMS-ISAN analysis package (Tremback, 1990) with inclusion of tracers Four-dimensional nudging (Newtonian relaxation) to data analyses with inclusion of tracers Digital filter Soil moisture initialization using real time cycling estimation from an off-line hydrological model (Gevaerd and Freitas, 2006)

^*Under development and/or evaluation