anchor.diff:  
     call model_run(h, u, v, eta, depth, dx, dy, wetmask, fu, fv, &
         dt, au, ar, botDrag, ah, slip, hmin, nTimeSteps, dumpFreq, avFreq, &
  -      maxits, eps, freesurfFac, thickness_error, debug_level, g_vec, rho0, &
  +      checkpointFreq, maxits, eps, freesurfFac, thickness_error, &
  +      debug_level, g_vec, rho0, &
         base_wind_x, base_wind_y, wind_mag_time_series, &
         spongeHTimeScale, spongeUTimeScale, spongeVTimeScale, &
         spongeH, spongeU, spongeV, &
  
positive.code:   ! then hide the long unsightly code there.
  
    namelist /NUMERICS/ au, ah, ar, botDrag, dt, slip, nTimeSteps, &
        dumpFreq, avFreq, hmin, maxits, freesurfFac, eps, &
        thickness_error, debug_level
  
    namelist /MODEL/ hmean, depthFile, H0, RedGrav
  
  
negative.code: 
  subroutine model_run(h, u, v, eta, depth, dx, dy, wetmask, fu, fv, &
      dt, au, ar, botDrag, ah, slip, hmin, nTimeSteps, dumpFreq, avFreq, &
      checkpointFreq, maxits, eps, freesurfFac, thickness_error, &
      debug_level, g_vec, rho0, &
      base_wind_x, base_wind_y, wind_mag_time_series, &
      spongeHTimeScale, spongeUTimeScale, spongeVTimeScale, &
      spongeH, spongeU, spongeV, &
  