[gradsusr] MLS CO observations in OpenGrADS

[James E. Johnson]

On Friday, July 13, 2012 09:30:10 am Heath, Nicholas wrote:
> Hi All,
> 
>  I am trying to view MLS CO data in GrADS.  Have any of you used GrADS for
> MLS data, and would you be willing to share your control file?  The data
> type is he5, a format I am very unfamiliar with.  I have tried following
> the guidelines laid out in the GrADS documentation, but have been
> unsuccessful.
> 
>  I am currently using OpenGrADS Version 2.0.1.oga.1.
> 
>  Thanks for your help!
> 
>  -Nick

Since GrADS is primarily intended for regularly gridded level-3 data, it 
doesn't make much sense to try to view the MLS CO data in GrADS. The MLS CO 
data are level-2 series of vertical profiles along the path of the orbit 
track; they are not spaced on a regular grid.

You try to write a control file to read the MLS CO level-2 data into GrADS. 
I have done it, but it also requires restructuring the data arrays so they are 
3-D with two bogus lon-X and lat-Y arrays, since the data consist of two 
dimensions: the first represents the along-track time profile (t), the second 
represents the vertical pressure level dimension (p). So data mixing ratio 
value point P(t,p) has a Latitude(t), Longitude(t), and Time(t), and 
Pressure(p). And then it will only make vertical profile plots or print out 
data values. You'd have to GRID the MLS series of vertical profiles yourself 
somehow to be useful in GrADS.

Its a bit of work, so I think you are better off reading in MLS Level-2 with 
some other package than GrADS. GrADS is really for gridded Level-3 data types.
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