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[Support #UPW-774161]: RE: [idvusers] Access to the Unidata and NSF xml catalogs in IDV

Hi Bill-

> I am sending you a smaller netcdf that I've been playing with but it only 
> includes one 3D atm parameter + a 2D terrain height so there should be less 
> chaff. I also ran it through the CF1.1 Orthodoxy Checker and it only gave me 
> a few problems.

Thanks for the sample.  If you change the units of nz_height_above_ground_t
to be unitless (units = ""), you can get your topography.  Since it's supposed
to be a dimensionless vertical coordinate, that would make sense.  Right
now the IDV sees the units of meters and assumes that as the vertical
dimension.  However, even with the dimensionless vertical coordinate,
the resulting image is not right.  I'm not sure if that's a result
of the "backwards" ordering of the the dimensions or what.

I have to talk to the netcdf gurus on this one and I'm not in the office
today.  I'll talk to them tomorrow.

> Once again, we appreciate your time.
No problem.

Don

> -----Original Message-----
> From: Capehart, William J
> Sent: Wednesday, February 13, 2008 09:17
> To: 'address@hidden'
> Subject: RE: [Support #UPW-774161]: RE: [idvusers] 
> atmosphere_hybrid_height_coordinate
> 
> 
> Thanks for getting back with me Don.  I;m on travel right now but I'll try to 
> get it to you today (if I can connect to the homeworld) or tomorrow.
> 
> Cheers & Thanks
> Bill
> 
> ================================================================
> Bill Capehart <address@hidden>   Associate Professor
> Institute of Atmospheric Sciences         Land Surface Processes
> 213 Mineral Industries Building                 Hydrometeorology
> South Dakota School of Mines and Technology Ph:  +1-605-394-1994
> 501 East Saint Joseph Street                Fax: +1-605-394-6061
> Rapid City, SD 57701-3995                Mobile: +1-605-484-5692
> =================== http://capehart.sdsmt.edu ==================
> 
> -----Original Message-----
> From: Unidata IDV Support [mailto:address@hidden]
> Sent: Tuesday, February 12, 2008 09:52
> To: Capehart, William J
> Subject: [Support #UPW-774161]: RE: [idvusers] Access to the Unidata and NSF 
> xml catalogs in IDV
> 
> Hi Bill-
> 
> Sorry for not getting back to you sooner on this.  They let us out of
> our cages last week, so we took some time off. ;-)
> 
> > I'm going to try to clarify one of my problems here:  I'm ccing it to the 
> > idvuser block too.
> >
> > I made a little progress in the CF1 formatting of the height above ground 
> > coordinate but I am not getting a fully satisfactory graphical rendering.
> >
> > I hope that clears some of my request up and hopefully I am doing a single 
> > silly mistake and missing "that one 'little' thing!"
> 
> I'm not expert on this, but....
> 
> I would normally expect:
> 
> float Air_Pressure(lon=50, lat=50, height_above_ground_p=15, time=9);
> 
> to be:
> 
> float Air_Pressure(time=9, height_above_ground_p=15, lat=50, lon=50);
> 
> but if you are getting something, then that shows we reorder well. ;-)
> 
> Do you have the Conventions tag set:
> 
> :Conventions = "CF-1.0";
> 
> Can send me the file?
> 
> Don
> 
> > -----
> >
> > We have some 3-d+time data in lat-lon + height above ground (not sea
> > level) and would like a better way to visualize it in IDV.  We've had no 
> > problem bringing it into IDV and viewing it as layers and IDV recognizes 
> > the data as having a vertical aspect (you can get crossectional planes 
> > through the domain by selecting the appropriate "level" in the dialog
> > box) when I do plan views.
> >
> > A followed the guide to CF1 for the hybrid_height_coordinate and based it 
> > after a successful one with CF1's sigma coordinate by reverse engineering a 
> > successful netcdf file that performs well in IDV.
> >
> > However, unlike sigma coordinates which can create a 2D surface that follow 
> > the underlying terrain (and float upward as you select higher
> > levels) when plotted in IDV, these fields are rendered as "flat" (not 
> > hugging an underlying surface) no different than if they were heights above 
> > sea level.
> >
> > Likewise, the X/Y vs Z cross-sections also begin at "sea level" and not at 
> > the ground level.
> >
> > Meanwhile all other aspects of the rendering (the georegistring in lat-lon 
> > space, and a 3D rendering of the surface terrain) are just fine.
> >
> > Am I doing something wrong (my interpretation of the relevant CF1 
> > attributes from an NCDUMP are below)?  Or does IDV only handle height, any 
> > height (above ground or sea level) as flat planes.
> >
> > Or better still is there a much easier way to do this? (I feel a bit silly 
> > doing this very plain jane concept as a hybrid coordinate, so I'm thinking 
> > dollars to donuts there is a much more basic way to render this data 
> > correctly.)
> >
> >
> >
> > float Geopotential_height_surface(lon=50, lat=50);
> > :long_name = "Geopotential height @ surface";
> > :units = "m";
> > :missing_value = 9999.0f; // float
> > :standard_name = "surface_altitude";
> > :coordinates = "lat lon";
> > :maxvalue = 3238.1f; // float
> > :minvalue = 0.0f; // float
> >
> > double unity(height_above_ground_p=15);
> > :long_name = "unity";
> > :units = "";
> > :missing_value = 9999.0; // double
> > :standard_name = "unity";
> > (this is just an array of 15 "ones" to go with the formula required for the 
> > hybrid height)
> >
> > double height_above_ground_p(height_above_ground_p=15);
> > :long_name = "Geopotential Height";
> > :standard_name = "atmosphere_hybrid_height_coordinate";
> > :units = "m";
> > :positive = "up";
> > :formula_terms = "a: height_above_ground_p b: unity orog:
> > Geopotential_height_surface";
> > :_CoordinateTransformType = "Vertical";
> > :_CoordinateAxisType = "GeoZ";
> > :_CoordinateAxes = "height_above_ground_p";
> > :_CoordinateZisPositive = "up";
> >
> > float Air_Pressure(lon=50, lat=50, height_above_ground_p=15, time=9);
> > :long_name = "Air_Pressure @ geopotential_height";
> > :units = "hPa";
> > :missing_value = -9999.0f; // float
> > :standard_name = "air_pressure";
> > :coordinates = "time height_above_ground_p lat lon";
> >
> > double lon(lon=50);
> > :long_name = "longitude";
> > :units = "degrees_east";
> > :standard_name = "longitude";
> > :_CoordinateAxisType = "Lon";
> > double lat(lat=50);
> > :long_name = "latitude";
> > :units = "degrees_north";
> > :standard_name = "latitude";
> > :_CoordinateAxisType = "Lat";
> >
> >
> > ----
> >
> > ================================================================
> > Bill Capehart <address@hidden>   Associate Professor
> > Institute of Atmospheric Sciences         Land Surface Processes
> > 213 Mineral Industries Building                 Hydrometeorology
> > South Dakota School of Mines and Technology Ph:  +1-605-394-1994
> > 501 East Saint Joseph Street                Fax: +1-605-394-6061
> > Rapid City, SD 57701-3995                Mobile: +1-605-484-5692
> > =================== http://capehart.sdsmt.edu ==================
> >
> > -----Original Message-----
> > From: Unidata User Support [mailto:address@hidden]
> > Sent: Friday, February 08, 2008 12:45
> > To: Capehart, William J
> > Subject: [Support #UPW-774161]: RE: [idvusers] Access to the Unidata and 
> > NSF xml catalogs in IDV
> >
> >
> > Capehart, William J,
> >
> > Your Ticket has been received, and a Unidata staff member will review it 
> > and reply accordingly. Listed below are details of this new Ticket. Please 
> > make sure the Ticket ID remains in the Subject: line on all correspondence 
> > related to this Ticket.
> >
> > Ticket ID: UPW-774161
> > Subject: RE: [idvusers] Access to the Unidata and NSF xml catalogs in IDV
> > Department: Support
> > Priority: Normal
> > Status: Open
> >
> >
> >
> > Please let us know if we can be of further assistance.
> >
> > Unidata User Support
> >
> >
> 
> 
> Ticket Details
> ===================
> Ticket ID: UPW-774161
> Department: Support IDV
> Priority: Normal
> Status: Open
> 
> 


Ticket Details
===================
Ticket ID: UPW-774161
Department: Support IDV
Priority: Normal
Status: Open