ncl绘制MODIS气溶胶数据图请教

当时年少春衫薄

各位前辈，我用ncl画modis图的时候出现以下问题不知道该怎么解决呢？
ncl: nc4file.c:2696: NC4_open: Assertion `0' failed.
Aborted
脚本如下，谢谢了

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"

begin

fn= "/home/siyuchen/MYD08_M3.A2016061.051.2016096104517.hdf/"

fi=addfile(fn,"r")

v=fi->Optical_Depth_Land_And_Ocean_Mean_Mean

v1=v(:,:)

wks= gsn_open_wks("ps","AOD-2016-03")

res=True

res@cnFillOn = True

res@cnLinesOn=False

res@cnLevelSelectionMode = "ManualLevels" ; set manual contourlevels

res@cnMinLevelValF=0; set min contour level

res@cnMaxLevelValF=200

res@cnLevelSpacingF=20; set contour spacing

plot=gsn_csm_contour_map(wks,v1,res)

end

当时年少春衫薄

谁能帮帮忙吗谢谢了啊