[ncl-talk] Calculating Velocity Potential (problem with saving output)

[Lyndon Mark Olaguera]

Dear All,

I'm trying to calculate the velocity potential (fixed grid) at 200 hPa from
NCEP daily reanalysis data. I am using the uv2sfvpF(u,v) function.

I am having trouble in saving the output to a netcdf file. How do I save
the calculated velocity potential with the same grid coordinates (i.e. same
lat order as the original file) as the original file?

I attached the link of the files that I'm working with and the script in
this email.
I highlight in red the line where I got stuck.

I'll appreciate any help.

Many thanks,

Lyndz


Here's my script:

;****************************************************
;This script calculates the velocity potential
;Input: U and V wind components
;****************************************************
begin
ufile = addfile("uwind200hPa_1975.nc","r")
vfile = addfile("vwind200hPa_1975.nc","r")
uwnd = ufile->uwnd(:,:,::-1,:)     ;sort coordinates usinf ::-1
printVarSummary(uwnd)

vwnd = vfile->vwnd(:,:,::-1,:)     ;sort coordinates using ::-1
printVarSummary(vwnd)

sfvp = uv2sfvpF(uwnd,vwnd)
sfvp = (/sfvp/1e6/)                   ;rescaling by 1e6

*copy_VarCoords(ufile,vp)*

vp at long_name = "velocity potential"
vp at units     = "m/s"
ncdf = addfile("test.nc" ,"c")  ; open output netCDF file

fAtt               = True            ; assign file attributes
fAtt at title         = "Velocity Potential"
fAtt at source_file   =  "
https://www.esrl.noaa.gov/psd/data/gridded/data.ncep.reanalysis.pressure.html
"
fAtt at Conventions   = "None"
fAtt at creation_date = systemfunc ("date")
fileattdef( ncdf, fAtt )            ; copy file attributes

ncdf->vp = vp
end


Here's the link to the files:

https://drive.google.com/drive/folders/0B9faET7Bc2o8MmtGS2VJLTB2NE0?usp=sharing
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