parameter (diffiso_alphadef=  1.0, diffiso_epsdef= 0.0)
      parameter (diffiso_coefdef = 1000., diffiso_slmaxdef = .005)
      parameter (diffiso_slreddef = 1.)
      parameter (delta_rhodef = -10.)
      parameter (sigzmindef = -1.e-4)
      parameter (cnst_upwinddef = 1., psi_relaxdef = 1.0)
      parameter (facz_cnstdef = 1.)
      parameter (diffiso_tscldef = 0.)

      parameter (rk_botdef = 0.)

c   Common block for constants you might like to change

      integer diffiso_order
      common/diff_param/ diffiso_alpha, diffiso_eps, diffiso_coef
     *                ,diffiso_slmax, sigzmin , diffiso_cadv, cupi, hupi
     *                ,cupi_ts, cupi_tr, facz_cnst, psi_rel, hupi_ts, hupi_tr
     *                ,diff_coef_tr, diff_coef_mo, slred, nslope, nkmap
     *                ,diffiso_order, initkmap, diff_dz_mo, delta_rho
     *                ,f0,tscl,rk_bot


      character*80 fbdif
      common /dif_io/ n_dif,fbdif,idf_dif

      logical use_tvd_vert, use_tvd_horz
      common /new_vert/  iv_top, use_tvd_vert, use_tvd_horz