请问wrf的结果中如何输出bottom_up_stag的值

嗳づ左岸の兔

wrf_user_intrp3d（var3d,vert, 等），其中vert要和var3d的垂直层数对应，然而如何得到变量的这些层的值呢？
求助各位大神！
以下是读取和插值时的不正确ncl代码，我主要问的内容就是如何得到pressure_levels的值

do it=0,ntimes-1

  tk = wrf_user_getvar(a,"tk",it)        ; T in K
  w  = wrf_user_getvar(a,"wa",it)        ; w averaged to mass points
  p  = wrf_user_getvar(a,"pressure",it) ;
  rh = wrf_user_getvar(a,"rh",it)        ; relative humidity;
  z  = wrf_user_getvar(a,"height",it)

  pressure_levels = (/500./)   
  nlevels  = dimsizes(pressure_levels)          ; number of pressure levels

  tk_plane = wrf_user_intrp3d(tk,p,"h",pressure_levels,0.,False)
  w_plane  = wrf_user_intrp3d( w,p,"h",pressure_levels,0.,False)
  p_plane  = wrf_user_intrp3d( p,p,"h",pressure_levels,0.,False)
  z_plane  = wrf_user_intrp3d( z,p,"h",pressure_levels,0.,False)
  rh_plane = wrf_user_intrp3d(rh,p,"h",pressure_levels,0.,False)
  
  e = p_plane*rh_plane/(0.622+rh_plane)
  mm=e*w_plane*0.622/(287*tk_plane)
  
  opts=True
  opts@MainTile="lalala"
  contour = wrf_contour(a,wks,mm(it,:,:),opts)
  plot=wrf_map_overlays(a,wks,(/contour/),pltres,mpres)

  end do