*If you are performing multiple runs (a run involving multiple hours of model time), you only run 3d.params on your initial run. === This page will guide you through what each of the parts of the 3d.params namelist covers === == 0000.0 start time == * This is the time from which you would like the model to initialize from. This time is independent of rampup. =='sounding' prefix name for sounding input and init output == * This is the name of your sounding file. (*.sound) ==98 98 77 nx,ny,nz; num nodes on coarse grid== * This is the number of nodes on your domain. i.e. if you have 1 km x 1 km resolution, your grid size would be 98 km x 98 km. If you had a resolution of 2 km x 2 km, your grid size would be double the nodes. nx * dx = grid size. ==3. 4 dt,ns; coarse grid step and num small steps == * dt is VERY important (time step in Courant number). You MUST make sure your dt is small enough to track your updraft. ==7.67 -1.75 um,vm; mean wind== * Sometimes it is necessary to move the domain box to follow a thunderstorm to make sure the storm never leaves the domain. This line allows the adjustment of 'u' movement and 'v' movement. == 0 0 0 bcx,bcy,bcz; bndry cond'n flags--see description below== * (Please fill in) ==1 upper-radiation BC on (1) or off (0)== * (Please fill in) ==9000. 36000. 72000. wavlen's (m) of true KDB radiation== * (Please fill in) ** 0 flag for 2D run (if set, use ny=5 and bcy=-1)** * (Please fill in) ==0.0 0.0 gx0,gy0; coordinates of the SW corner of grid== * (Please fill in) ==1000. 1000. dx,dy; coarse grid spacing== * This is where you will decide which resolution you would like. Most supercell runs take 2km x 2km x 500 km. However, feel free to use whichever you prefer. * Grid spacing is in meters. To obtain the domain size, multiply the coarse grid (98 98) by the coarse grid spacing. ==250. 0 dz, stretching flag (on (1) or off (0));if on, read stretch.dat== * See previous. ==0 terrain type--see description below== * VERY IMPORTANT! The default flag with UWCOMMAS is type 4...unless you want a mountain in your run, change this to 0. See description of terrain types below. ==10000. 10000. 1000. x_scale,y_scale,z_scale; terrain parameters== * (Please fill in) ==10000. 10000. 00000. x_scale2,y_scale2,y_len; terrain parameters== * (Please fill in) **90000. 90000. 0. x_0,y_0,z_0; terrain parameters ** * (Please fill in) ==1 0 num bubbles and perturb'n theta; bubble params below == * num bubbles is the number of bubbles in your run. These bubbles are the convective initiation for the model. * perturb'n theta is how warm the bubble starts ==35000. 30000. 1500. 9000. 9000. 1500. xpos,ypos,zpos,xrad,yrad,zrad == * This is the position and size of the bubble ==0== * (Please fill in) ==0 0 0 0 0 0== * (Please fill in) ==0 inflow bc for scalar (0); not used== * (Please fill in) ==200.0 max sound speed (cs < 0 => base state)== * (Please fill in) ==0 compressible Boussinesq (1) or fully compressible (0)== * This is just a flag for if you'd like to use an assumption of a Boussinesq fluid or if you want to assume fully compressible ==0 Boussinesq hydrostatic (1) or non-hydrostatic (0)== * Similar to the previous flag. This turns hydrostatic assumptions on/off ==-1 displacements (0) or Boussinesq vorticity (1) or nothing (-1) == * (Please fill in) ==0.0e-4 Coriolis parameter== * Just what it sounds like :-) ==0 noise on (1) or off (0)== * Just another flag that means what it says ==0.e-4 anoise; noise amplitude (fraction of reference theta)== * (Please fill in) ==0. cnoise; cutoff length for noise spectrum (in grid units) == * (Please fill in) ==0. tnoise; time at which noise is added== * (Please fill in) ==1 sub-gridscale mixing on (1) or off (0)== * (Please fill in) == 00. alowk0; vertical background damping== * (Please fill in) ==-1. ahighk; vertical background damping== * (Please fill in) ==0.21 Cm (0.21); mixing coeff== * (Please fill in) ==3.0 1/Pr (1.5 or 3.); inverse Prandtl num == * (Please fill in) ==0.20 f4damp (f4damp * .0625/(2*dt) is actual model coefficient)== * (Please fill in) ==95500. rayleigh damper initial hgt== * (Please fill in) ==.000 rayleigh damper tau== * (Please fill in) ==0.2 vertical implicit coef (0 to 1)== * (Please fill in) ==0.15 asselin time filter== * (Please fill in) ==0.00 non-dim divergent damper coeff (0.0)== * (Please fill in) **3.0e-3 drag coeff for velocity** * (Please fill in) ==3.0e-3 drag coeff for heat== * (Please fill in) ==2.1e-3 drag coeff for moisture== * (Please fill in) ==30.0 outflow gravity wave speed== * (Please fill in) == These next several lines are descriptors of previous flags== BCX,BCY: 0 -> outflow conditions 1 -> nested grid -1 -> periodic -2 -> symmetry conditions at 0 and L -3 -> symmetry conditions at 0, outflow at L -4 -> outflow conditions at 0, symmetry at L BCZ : 0 -> freeslip 1 -> surface layer (not implemented) terrain_type: 0 -> no terrain; 1 -> hat in x, h = h(x) 2 -> hat in y h = h(y) 3 -> x,y hat h = h(x,y) 4 -> cos^4 hat in x,y h = h(x,y) elongated in y separate upstream/downstream x scales