[gradsusr] Relative topography RT1000-500 hPa

[Muhammad Rahiz]

Djordje, the following would get the difference between ht1000 and ht500.

'sdfopen output.nc'
'set t 1 last'

'set lev 500'
'd500 = d'

'set lev 1000'
'd1000 = d'

'd d1000-d500'

You can then write the result to a file by specifying the type of output 
you wanted in "set gxout".




Muhammad Rahiz
Researcher & DPhil Candidate (Climate Systems & Policy)
School of Geography & the Environment
University of Oxford

On Thu, 17 Feb 2011, Djordje Romanic wrote:

> Dear GrADS Userds,
>  
> Using NCEP/NCAR 6-hours data from the
> http://nomad3.ncep.noaa.gov:9090/dods/reanalyses/reanalysis-1/6hr/pgb/pgb.info I
> need to calculate the relative topography RT1000-500 hPa, i.e. difference between
> geopotential height of 500 hPa pressure level and 1000 hPa pressure level, for a
> 30-years period (1961-1990) and for the whole globe. Please, does anyone can help me
> how to do it with GrADS and how to write the result in a file?
>  
> Thanks in advance.
>  
> Kind regards,
>  
> Djordje
> 
>