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[IDV #LMW-673348]: Ocean glider data open as Track file problem

> Hello,
> 
> I am Matias Bonet I work for the AODN (Australian ocean data network
> http://portal.aodn.org.au/webportal/) based at the University of Tasmania.
> We are using netcdf/CF convention to define Glider trajectories. The problem
> comes when we want to open this files in IDV.
> 
> Here we have a thredds catalog with data from different gliders (Slocum and
> Seagliders)
> http://opendap-vpac.arcs.org.au/thredds/catalog/IMOS/ANFOG/catalog.html
> 
> As the Australian ocean data network we receive the data from all the
> gliders around australia. Ups sorry, a glider is a submarine
> http://www.youtube.com/watch?v=YFyu3Lm_xlM&feature=related  I also attach a
> capture using IDV about how it look like.
> 
> 
> The problem is that the track file reader does not follow the CF
> conventions.
> http://cf-pcmdi.llnl.gov/documents/cf-conventions/1.5/ch05s05.html There are
> a few things that are not right:
> 
> - Is using the variable names instead of variable attributes even in this
> case we have the same names but in upper case and does not work either.
> - The variable for the Z index must be named Altitude for the IDV to be
> interpreted and also we have to change the units to -1.0meters to go above
> the sea level.
> 
> 
> I added a NCML file to modify our netcdf files the changes basically are:
> 
> - Change TIME dimension to lower case (imply change all the shapes to
> time in lower case).
> - Change of LATITUDE and LONGITUDE to lower case.
> - Change variable DEPTH to altitude and units of it to -1.0meters.
> 
> The changes are not really hard (i thing). Is a matter of add to lower in
> the string comparation and also a check to altitude or depth and in case
> that the variable name is depth then use tha attribute positive="UP or
> DOWN".
> 

Hi Matias,
         The problem is not simply up case or lower case here. The IDV depends 
on the CDM library to define the 
trajectory data type, and I believe the ncml wrapper you created actually 
transfers your glider dataset into a recognizable trajectory data type. The CDM 
also moves to the feature type to better support the trajectory dataset,
and I want to make sure your ncml file is good too. If you just want to display 
in the IDV, you can use the ncml to define a new glider data source type, this 
may help you too.



Yuan


> I added to the link to the CF conventions for trajectories
> http://cf-pcmdi.llnl.gov/documents/cf-conventions/1.5/ch05s05.html
> 
> Thank you very much.
> 
> Matias.
> 
> 


Ticket Details
===================
Ticket ID: LMW-673348
Department: Support IDV
Priority: Normal
Status: Open