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[IDV #XWV-899527]: IDV - sigma levels in netcdf file

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  • Subject: [IDV #XWV-899527]: IDV - sigma levels in netcdf file
  • Date: Sat, 10 Feb 2007 06:34:00 -0700
Hi Mark-

> > The problem is that your latitudes change direction at the 52 point:
> I am guessing you meant longitude.

No, I meant latitude (second number).  Notice that before point 51 the values 
are increasing, but then they start decreasing.

> >
> > [48]: 18.218628,-87.33871,5673.8726
> > [49]: 12.376205,-87.41195,5656.7305
> > [50]: 6.261139,-87.45691,5609.3237
> > [51]: 0.0,-87.47207,5539.839
> > [52]: -6.261139,-87.45691,5506.035
> > [53]: -12.376221,-87.41195,5472.393
> > [54]: -18.218628,-87.33871,5419.2974
> Yes, these values are correct and they make sense.
> 
> > where I would expect them to change at the 103 point since yc is
> > dimensioned to be 102.  Am I missreading that?  Is this an artifact
> > of the pole?
> 
> It is not as much as it is changing direction at point 52 as it is
> crossing the prime meridian at this location (further up in the data it
> crosses the dateline at point 52).  I have attached an image which shows
> the projection from this dataset with the map and lat/lon lines.

The image didn't come through, could you resend.  I understand the
crossing of the prime meridian - it's the change in latitude direction
that I don't understand.  Perhaps he picture will make it clearer.

> I am not certain as to why one would expect the longitude direction to
> change at the 103 point.

Well, not change direction so much as start over at the first longitude
again.  Same with latitude.


Don


Ticket Details
===================
Ticket ID: XWV-899527
Department: Support IDV
Priority: Normal
Status: Open